TY - JOUR
TI - Morphological variation and female reproductive success in two sympatric Trillium species: evidence for phenotypic selection in Trillium erectum and Trillium grandiflorum (Liliaceae)
AU - Irwin, Rebecca E.
T2 - American Journal of Botany
AB - I investigated the mating systems and phenotypic variation of two sympatric spring ephemerals, Trillium erectum and T. grandiflorum (Liliaceae), and phenotypic selection acting through female reproductive success for 11 morphological characters in five sympatric populations of the two species. I examined the degree of self-compatibility, pollinator-visitation rates, and pollen limitation of fruit and seed production in both species. Both Trillium species were self-compatible, but outcrossed flowers produced more successful fruits and seeds than self-pollinated flowers. Pollinator-visitation rates to the two species were low compared to other insect-pollinated spring ephemerals. In addition, both T. erectum and T. grandiflorum experienced pollen limitation in fruit and/or seed production; however, levels of fecundity in both species may be influenced by resource availability as well. I found significant phenotypic variation in 11 morphological characters within and among the five study populations. The sizes of all morphological characters were positively correlated. In general, larger T. erectum and T. grandiflorum produced more seeds. Phenotypic selection analysis revealed that direct and indirect selection acted on the size of morphological characters for both species. But there was no detectable selection acting on plant shape. This study reveals that variation in plant size exists within and among populations of both species, and this variation is associated with variance in female reproductive success. Spatial and temporal variation in pollinator and/or resource abundance may play a role in the phenotypic variation exhibited by both Trillium species.
DA - 2000/2//
PY - 2000/2//
DO - 10.2307/2656907
VL - 87
IS - 2
SP - 205-214
J2 - American J of Botany
LA - en
OP -
SN - 0002-9122 1537-2197
UR - http://dx.doi.org/10.2307/2656907
DB - Crossref
ER -
TY - JOUR
TI - Hummingbird avoidance of nectar‐robbed plants: spatial location or visual cues
AU - Irwin, Rebecca E.
T2 - Oikos
AB - Broad‐tailed and rufous hummingbirds avoid plants and flowers that have recently been visited by nectar‐robbing bees. However, the cues the hummingbirds use to make such choices are not known. To determine the proximate cues hummingbirds use to avoid visiting nectar‐robbed plants, I conducted multiple field experiments and one aviary study using the nectar‐robbed, hummingbird‐pollinated plant Ipomopsis aggregata . In the first field experiment, free‐flying hummingbirds were presented with plants in which I manipulated nectar volume and the presence of nectar‐robber holes. Hummingbirds visited significantly more plants with nectar and probed more available flowers on those plants, regardless of the presence of nectar‐robber holes. Thus, I hypothesized that hummingbirds may avoid robbed plants based on their spatial memory of unrewarding plants and/or visual cues that nectar absence provides. In an aviary study, I removed spatial cues by re‐randomizing the position of plants after each hummingbird‐foraging bout, but hummingbirds still selected plants with nectar. Nectar may provide a visual cue in I. aggregata flowers because corollas are translucent, and nectar is visible through the side of the corolla. To determine if hummingbirds use this visual cue to avoid plants with no nectar, I masked corolla translucence in a field study by painting flowers with acrylic paint. Hummingbirds still visited significantly more plants with nectar and probed more flowers on those plants, whether or not the corollas were painted. These results suggest that hummingbirds use nectar as a proximate cue to locate and avoid non‐rewarding, nectar‐robbed plants, even in the absence of spatial cues and simple visual cues.
DA - 2000/12//
PY - 2000/12//
DO - 10.1034/j.1600-0706.2000.910311.x
VL - 91
IS - 3
SP - 499-506
J2 - Oikos
LA - en
OP -
SN - 0030-1299 1600-0706
UR - http://dx.doi.org/10.1034/j.1600-0706.2000.910311.x
DB - Crossref
ER -
TY - JOUR
TI - CONSEQUENCES OF NECTAR ROBBING FOR REALIZED MALE FUNCTION IN A HUMMINGBIRD-POLLINATED PLANT
AU - Irwin, Rebecca E.
AU - Brody, Alison K.
T2 - Ecology
AB - The effects of nectar robbers on plants and their mutualistic pollinators are poorly understood due, in part, to the paucity of studies examining male reproductive success in nectar-robbed plants. Here we measured the effects of a nectar-robbing bumblebee, Bombus occidentalis, on realized male reproductive success (seeds sired) in a hummingbird-pollinated plant, Ipomopsis aggregata. To determine the effects of nectar robbing on paternity, we used a series of experimental populations of plants containing a known allozyme marker. In each population, we experimentally controlled the levels of nectar robbing on each I. aggregata plant by cutting a hole in the corolla with dissecting scissors and removing nectar with a micro-capillary tube. We measured hummingbird-pollinator foraging behavior and fruit and seed production (maternal function) for each plant. We then genotyped seeds for the allozyme marker to determine the number of seeds sired by plants with known levels of robbing. Heavy nectar robbing (> 80% of flowers robbed) significantly reduced the number of seeds sired, as well as the number of seeds produced due to pollinator avoidance of heavily robbed plants. Total plant reproduction, both male and female contributions, were reduced by 50% due to high levels of robbing. To date, no other studies have measured the effects of nectar robbing on realized male function (number of seeds sired). Ours is the first study to demonstrate that robbing can simultaneously decrease realized male reproductive success as well as female reproductive success, and that the effects are incurred indirectly through pollinator avoidance of robbed plants.
DA - 2000/9//
PY - 2000/9//
DO - 10.2307/177481
VL - 81
IS - 9
SP - 2637-2643
J2 - Ecology
LA - en
OP -
SN - 0012-9658
UR - http://dx.doi.org/10.1890/0012-9658(2000)081[2637:CONRFR]2.0.CO;2
DB - Crossref
ER -
TY - JOUR
TI - MSL1 plays a central role in assembly of the MSL complex, essential for dosage compensation in Drosophila
AU - Scott, M. J.
T2 - The EMBO Journal
AB - Article4 January 2000free access MSL1 plays a central role in assembly of the MSL complex, essential for dosage compensation in Drosophila Maxwell J. Scott Corresponding Author Maxwell J. Scott Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Lewis L. Pan Lewis L. Pan Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Sheralee B. Cleland Sheralee B. Cleland Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Andrea L. Knox Andrea L. Knox Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Present address: Wellcome/CRC Institute, Tennis Court Road, Cambridge, CB2 1QR UK Search for more papers by this author Jörg Heinrich Jörg Heinrich Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Maxwell J. Scott Corresponding Author Maxwell J. Scott Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Lewis L. Pan Lewis L. Pan Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Sheralee B. Cleland Sheralee B. Cleland Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Andrea L. Knox Andrea L. Knox Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Present address: Wellcome/CRC Institute, Tennis Court Road, Cambridge, CB2 1QR UK Search for more papers by this author Jörg Heinrich Jörg Heinrich Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand Search for more papers by this author Author Information Maxwell J. Scott 1, Lewis L. Pan1, Sheralee B. Cleland1, Andrea L. Knox1,2 and Jörg Heinrich1 1Institute of Molecular BioSciences, Massey University, Palmerston North, New Zealand 2Present address: Wellcome/CRC Institute, Tennis Court Road, Cambridge, CB2 1QR UK *Corresponding author. E-mail: [email protected] The EMBO Journal (2000)19:144-155https://doi.org/10.1093/emboj/19.1.144 PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info In male Drosophila, histone H4 acetylated at Lys16 is enriched on the X chromosome, and most X-linked genes are transcribed at a higher rate than in females (thus achieving dosage compensation). Five proteins, collectively called the MSLs, are required for dosage compensation and male viability. Here we show that one of these proteins, MSL1, interacts with three others, MSL2, MSL3 and MOF. The latter is a putative histone acetyl transferase. Overexpression of either the N- or C-terminal domain of MSL1 has dominant-negative effects, i.e. causes male-specific lethality. The lethality due to expression of the N-terminal domain is reduced if msl2 is co-overexpressed. MSL2 co-purifies over a FLAG affinity column with the tagged region of MSL1, and both MSL3 and MOF co-purify with the FLAG-tagged MSL1 C-terminal domain. Furthermore, the MSL1 C-terminal domain binds specifically to a GST–MOF fusion protein and co-immunoprecipitates with HA-tagged MSL3. The MSL1 C-terminal domain shows similarity to a region of mouse CBP, a transcription co-activator. We conclude that a main role of MSL1 is to serve as the backbone for assembly of the MSL complex. Introduction Drosophila melanogaster dosage compensate (i.e. equalize X-linked gene products) by doubling the amount of gene expression from the one male X chromosome to equal that from the two female X chromosomes (reviewed by Bashaw and Baker, 1996; Lucchesi, 1998). Males homozygous for loss-of-function mutations in the male-specific lethal1 (msl1), male-specific lethal2 (msl2), male-specific lethal3 (msl3), maleless (mle) or males absent on the first (mof) genes die due to a failure to dosage compensate. Antibody-binding studies have shown that the MSL1, MSL2, MSL3, MLE and MOF proteins, collectively called the MSLs, co-localize to hundreds of sites along the length of the male X chromosome (Lucchesi, 1998). Acetylation of histone H4 at Lys16 is associated preferentially with the male X chromosome and is dependent on the binding of the MSLs (Turner et al., 1992; Bone et al., 1994). MOF shows homology to the ESA1 and Tip60 histone acetyl transferases (Hilfiker et al., 1997; Smith et al., 1998). Histone acetylation would decrease the affinity of histone for DNA (Struhl, 1998) and could destabilize higher order chromatin structure by weakening the interaction between adjacent nucleosomes (Luger et al., 1997). Furthermore, several transcription co-activators have been shown to have histone acetyl transferase activity (Brownell and Allis, 1996; Struhl, 1998). This suggests that altering chromatin structure via histone acetylation is a key element of the mechanism by which the MSLs increase X-linked gene expression in males. Of the other MSLs, MLE codes for an RNA–DNA helicase (Lee et al., 1997), MSL2 is a RING finger protein (Bashaw and Baker, 1995; Kelley et al., 1995; Zhou et al., 1995) and MSL3 is a chromodomain protein (Koonin et al., 1995). MSL1, however, has no recognizable domains but does have regions that are rich in acidic amino acids (Palmer et al., 1993). The MSL complex is not unique in containing both an RNA helicase and histone acetyl transferase. The CREB-binding protein (CBP) transcription co-activator is a histone acetyl transferase (Bannister and Kouzarides, 1996) and binds to RNA helicase A (Nakajima et al., 1997). Coupling a helicase with a histone acetyl transferase could be advantageous as histone acetylation could destabilize the chromatin structure and thus facilitate passage of the helicase along the chromosome. There are several lines of evidence suggesting that the MSLs form a complex. First, the localization of any one of the MSLs to the male X chromosome requires all five msl+ activities (Palmer et al., 1994; Gorman et al., 1995; Kelley et al., 1995; Gu et al., 1998). Furthermore, the stability of the MSL1 protein is strongly dependent on the presence of MSL2 (Chang and Kuroda, 1998). Similarly, MSL3 stability is dependent upon MSL1 and MSL2 (Gorman et al., 1995). MSL2 and MSL3 interact with MSL1 in a yeast two-hybrid system (Copps et al., 1998). MSL1, MSL2 and MSL3 co-immunoprecipitate and chromatographically co-fractionate from Drosophila SL2 cell extract (Copps et al., 1998). MLE, however, appears not to be tightly associated with the other MSLs. In addition to the MSLs, the X-linked non-coding roX1 (RNA on the X chromosome) and roX2 genes may have a role in dosage compensation. The male-specific accumulation of roX1 and roX2 RNAs is dependent upon the MSLs, and roX1 RNA ‘paints’ the male X chromosome in a manner strikingly similar to the ‘painting’ of the mammalian inactive X chromosome by Xist RNA (Amrein and Axel, 1997; Meller et al., 1997). Since an RNA component is essential for association of MLE with the X chromosome (Richter et al., 1996), this suggests that a possible role for the roX RNAs is to stabilize the interaction of MLE with the other MSLs (Meller et al., 1997; Chang and Kuroda, 1998). The binding of MSL1 and MSL2 to several ‘high affinity’ sites on the X chromosome does not require MLE, MOF or MSL3 (Lyman et al., 1997). Furthermore, the binding of these three proteins to the male X chromosome is absolutely dependent on MSL1 and MSL2 (Gu et al., 1998). Together, these results suggest that the MSLs may bind sequentially to the X. In the first step, the MSL1 and MSL2 complex binds to high affinity sites on the X. Secondly, MSL1 and MSL2 then recruit MSL3, MLE and MOF to the X. The MSL complex does not associate with the female X chromosomes because MSL2 protein is absent from females (Bashaw and Baker, 1995; Kelley et al., 1995; Zhou et al., 1995). With the long-term goal of improving our understanding of the mechanism of dosage compensation, we have sought to identify the domains of MSL1 that are important for function in vivo. We find that overexpression of two regions of MSL1 causes male-specific lethality, i.e. they behave as dominant-negative mutant forms of MSL1. We present genetic and biochemical evidence that one region interacts with MSL2, the other with both MSL3 and MOF. Our results suggest a central role for MSL1 in assembly of the MSL complex. Results Overexpression of regions of MSL1 causes male-specific lethality We hypothesized that overexpression of a truncated version of MSL1 could cause male-specific lethality if it bound to one or more of the MSLs and reduced the concentration of this MSL available to bind to endogenous MSL1 below a critical threshold required for dosage compensation (and thus male viability). Transgenic flies homozygous for an msl1 expression construct (Figure 1) were raised at 30°C and heat shocked daily for 1 h at 37°C to maximize MSL1 protein synthesis. Expression of MSL1 and its truncated derivatives was controlled with the hsp70 heat-shock promoter, which has significantly higher constitutive activity at 30°C compared with 22°C (O'Brien and Lis, 1991). We found that there was 100% male lethality in transformant lines carrying either the FΔ84, FΔ84ΔC*, FN, C or FC constructs (Table I). There was also a smaller but nevertheless significant decrease in male viability in lines expressing either the FMSL1, Δ84 or Δ84ΔC* proteins. Transformant lines expressing either full-length MSL1 or the MID region of MSL1 under these conditions produced approximately equal numbers of males and females (Table I). These results suggest that there are at least two regions of MSL1, one near the N-terminus and the other at the C-terminus, defined by FN and C, respectively, which could be important for assembly of the MSL complex in vivo. Interestingly, although the FLAG-tagged FΔ84 and FΔ84ΔC* proteins are essentially identical to the Δ84 and Δ84ΔC* proteins, respectively, overexpression of the former has a much more severe effect on male viability (Table I). Similarly, overexpression of FLAG-tagged MSL1 (FMSL1) but not MSL1 resulted in a small but significant decrease in male viability. Figure 1.msl1 constructs used in this study. The numbers at the beginning and end of each construct indicate the region of MSL1 that is expressed. Full-length MSL1 (1039 amino acids) is shown at the top. The proteins encoded by FΔ84, FΔ84ΔC* and FC are identical to those encoded by Δ84, Δ84ΔC* and C, respectively, except that the former encode a FLAG tag (DYKDDDDK, shaded black) at their N-termini. The FMSL1 protein is identical to MSL1 except that it has a FLAG peptide at the N-terminus and a linker peptide (RPQKTT, shaded with dots) between the FLAG and the start of MSL1. Features of MSL1 that are highlighted are a predicted amphipathic α-helix (cross-hatched, amino acids 96–172), a highly acidic stretch (shaded grey, amino acids 368–391) and a region where half the amino acids are either S, T or P (chequered, amino acids 708–801). Also indicated is a region (amino acids 712–988) that shows similarity to amino acids 863–1117 of mouse CBP (see Results). The expression of all MSL1 derivatives in transgenic flies was controlled by the hsp70 promoter. Download figure Download PowerPoint Table 1. Overexpression of FLAG-tagged derivatives of MSL1 causes male-specific lethality Construct a Males Females Male/female ratio b hsp·msl1 319 289 1.1 FMSL1 377 565 0.67 Δ84 296 633 0.46 FΔ84 0 272 0 Δ84ΔC* 416 1041 0.4 FΔ84ΔC* 0 374 0 FN 0 189 0 MID 601 559 1.08 C 0 425 0 FC 0 666 0 a All lines were homozygous for the construct. Vials were heat shocked daily for 1 h at 37°C. For simplicity, data are shown for just one line although at least two and usually three lines were examined for each construct, all of which gave a similar result. b Significant reduction in male viability (p <0.01, χ2 test) for all lines except hsp·msl1 and MID. Viability of FΔ84 but not C males is reduced if heterozygous for msl2 If the dominant-negative mutant forms of MSL1 are binding to a particular MSL, then lowering the concentration of that MSL could reduce male viability further, since less of the MSL is available to bind to full-length MSL1. The concentration of a particular MSL was reduced by 50% by crossing either an FΔ84 or C line with a null mutation for an msl (Table II). This experiment could not be carried out easily with mof since it is X-linked (Hilfiker et al., 1997). In order to detect if any of the msl mutations can enhance the male-lethal effects of either FΔ84 or C, conditions were used that result in only a modest reduction in male viability. Thus, the offspring of the crosses carry only one copy of either the FΔ84 or C transgenes (homozygous flies were used in Table I), and were raised under milder incubation conditions (either 22°C incubation or 30 min heat shock) than used previously (Table I). This resulted in lower expression of FΔ84 or C proteins. The viability of males carrying the FΔ84 construct was reduced significantly (p <0.01, χ2 test) if the males were heterozygous for msl2 (Table II). There was no significant difference in the relative viability of heterozygous msl1, mle or msl3 males compared with their respective wild-type siblings (Table II). These results indicate that in FΔ84 males the concentration of MSL2 available for dosage compensation is limiting. This is perhaps not surprising since MSL2 is the male-specific MSL (Zhou et al., 1995). However, there was no significant difference in the relative viability of heterozygous msl2, mle or msl3 C males compared with their respective wild-type siblings (Table II). While this assay was not informative about which MSL could be interacting with the C region, it would seem unlikely that it is MSL2 given the results with the FΔ84 construct. Table 2. Viability of FΔ84 but not C males is reduced if heterozygous for msl2 Constructa msl msl/+ +/+ Males Females M/F ratio Males Females M/F ratio FΔ84b msl1 100 301 0.33 147 390 0.38 msl2 42 495 0.08c 105 481 0.22 mle 141 498 0.28 151 521 0.29 msl3 158 406 0.39 166 393 0.42 Cd mle 65 189 0.34 40 157 0.26 msl2 45 140 0.32 43 131 0.33 msl3 41 180 0.22 19 170 0.12 a FΔ84 Crosses were raised at 22°C and shocked daily at 37°C for 1 h. C crosses were raised at 30°C and shocked daily at 37°C for 30 min. b Full genotype of FΔ84 crosses (female×male): msl1, w P[FΔ84 w+]34×msl1γ269 bw/CyO; msl2, w P[FΔ84 w+]34×msl2γ136 cn bw/CyO; mle, w P[FΔ84 w+]34×mleγ286 bw/CyO; and msl3, w P[FΔ84 w+]34×mle31 red/TM3, Sb Ser. c Viability significantly reduced (p <0.01, χ test) relative to +/+ siblings. d Full genotype of C crosses (female×male): msl2, y w; P[C w+]25×msl2γ136 cn bw/CyO; mle, y w; P[C w+]25×mleγ286 bw/CyO; and msl3, y w; P[C w+]25×mle31 red/TM3, Sb Ser. Co-expression of MSL2 rescues males from the lethal effects of dominant-negative mutant forms of MSL1 (ΔMSL1) If FΔ84 and MSL2 do interact, then co-expression of both proteins should improve male viability compared with expression of FΔ84 alone. An FΔ84 line was crossed with a transformant line carrying an hsp·msl2 construct (msl2 expression driven by the hsp70 promoter). The offspring of the cross were raised at 30°C and heat shocked daily for 1 h at 37°C. The viability of males that carried both constructs was significantly improved compared with males that carried only the FΔ84 construct (Table III). Rescue of FΔ84 males was not complete, probably because the FΔ84 protein contains the C-terminal domain of MSL1 that associates with other MSLs (see below). Table 3. Co-expression of MSL2 rescues males from the lethal effects of dominant-negative mutant forms of MSL1 (ΔMSL1) Construct a ΔMSL1 ΔMSL1 + msl2 Males Females M/F ratio Males Females M/F ratio FΔ84 b 86 354 0.24 268 474 0.57 c FΔ84ΔC* 172 336 0.51 403 415 0.97c FN 23 110 0.21 129 157 0.82c a Crosses were raised at 30°C and heat shocked daily at 37°C for 1 h. Offspring contained either one copy of the ΔMSL1 construct or one copy of the ΔMSL1 construct plus one copy of hsp·msl2. Thus, expression of the msl1 constructs and msl2 was controlled by the hsp70 promoter. Under these incubation conditions, expression of msl2 has no effect on female viability (data not shown). b Full genotype of crosses (female×male): FΔ84, w1118; P[FΔ84 w+]33×P[hsp·msl2]13/TM3, Sb e; FΔ84ΔC*, w1118; P[FΔ84ΔC* w+]13×P[hsp·msl2]13/TM3, Sb e; FN alone, y w × y w; P[FN w+]13; and FN + msl2, y w P[hsp·msl2]14×y w; P[FN w+]13. c Significant improvement in male viability (p <0.01, χ2 test) compared with males that carry only the msl1 construct. To identify the region of MSL1 that interacts with MSL2, transformants carrying either the FΔ84ΔC* or FN constructs were also crossed with hsp·msl2. Co-expression of msl2 significantly improves the viability of both FΔ84ΔC* and FN males (Table III). These results suggest that the domain of MSL1 that interacts with MSL2 maps to the region expressed by the FN construct. In comparison, the viability of C males was not improved by co-expression of MSL2, MLE, MSL3 or MOF (data not shown). Dominant-negative mutant forms of MSL1 interact with MSL2, MSL3 and MOF Immunoprecipitation assays show that MSL1 and MSL2 are part of a complex (Kelley et al., 1995), and yeast two-hybrid experiments suggest that MSL1 and MSL2 interact directly in Drosophila (Copps et al., 1998). We used FLAG affinity chromatography to determine if any of the dominant-negative truncated versions of MSL1 associate with MSL2. To maximize the likelihood of detecting an association between any of the MSL1 forms and MSL2 in a crude fly extract, we co-overexpressed MSL2 with each FLAG-tagged form of MSL1. FMSL1, FΔ84, FΔ84ΔC*, FN and FC transformant lines were each crossed with hsp·msl2 and the offspring given a single heat shock to induce MSL1 and MSL2 protein synthesis prior to homogenization. Crude cell lysate was applied to an anti-FLAG affinity gel. After repeated washing of the column, bound protein was eluted with an excess of free FLAG peptide. All of the FLAG-tagged versions of MSL1 bound specifically to the anti-FLAG affinity gel (Figure 2A). There was no significant retention of MSL2 alone on the affinity gel (Figure 2B). However, MSL2 did bind to the affinity gel if it was co-expressed with FMSL1, FΔ84, FΔ84ΔC* or FN, but not FC (Figure 2B). We conclude that the dominant-negative effect of the FN region of MSL1 (amino acids 85–263) is due to association with MSL2. This is consistent with yeast two-hybrid experiments which have shown that part of the FN region of MSL1 (amino acids 85–186) associates with MSL2 (Copps et al., 1998). Figure 2.FLAG affinity chromatography of FLAG-tagged MSL1–MSL2 complexes. Protein extracts were prepared from transformant flies that co-overexpressed MSL2 and either FLAG-MSL1 (lanes 1 and 2), FΔ84ΔC* (lanes 3 and 4), FN (lanes 5 and 6), FΔ84 (lanes 7 and 8) or FC (lanes 9 and 10). Protein extract was also prepared from a line that overexpressed MSL2 alone (lanes 11 and 12). Aliquots of either unpurified extract (E; lanes 1, 3, 5, 7, 9 and 11) or FLAG affinity-purified protein (P; lanes 2, 4, 6, 8, 10 and 12) were separated by SDS–PAGE and transferred to nitrocellulose membranes. The amount loaded on the extract lanes corresponds to ∼8% of the material applied to the FLAG affinity gel. Western blots were incubated with either anti-MSL1 (A) or anti-MSL2 (B) primary antibodies. Download figure Download PowerPoint Similar affinity chromatography experiments were performed to determine if MOF, MSL3 or MLE associate with any of the dominant-negative mutant forms of MSL1. FMSL1, FΔ84, FΔ84ΔC* and FC transformant lines were each crossed with either hsp·mof or hsp·msl3 and the offspring heat shocked prior to homogenization to induce MSL1 and either MOF or MSL3 synthesis. The crude fly extracts were applied to FLAG affinity columns and bound material eluted with excess FLAG peptide. All of the FLAG-tagged forms of MSL1 were retained on the affinity gels (Figures 3A and 4A). Both MOF (Figure 3B) and MSL3 (Figure 4B) co-purified with FMSL1, FΔ84 and FC, but not FΔ84ΔC*. This suggests that both MOF and MSL3 interact with the C-terminal domain of MSL1 and that these associations are responsible for the dominant-negative effects of this region of MSL1. In contrast, MLE did not co-purify with either the FΔ84 or FC proteins (Figure 5). This is consistent with immunoprecipitation and chromatographic purification experiments that have shown that MLE is only weakly associated with the MSL complex (Copps et al., 1998). Immunofluorescence studies have shown that mle+ function is required for the localization of MOF and MSL3 to the X chromosome (Gu et al., 1998). One interpretation of this result is that MLE interacts directly with either MSL3 or MOF. To test this prediction, we co-overexpressed FC, MSL3, MOF and MLE and partially purified the protein complex over FLAG affinity columns. FC (Figure 5A, lanes 7 and 8), MSL3 and MOF (data not shown), but not MLE (Figure 5B, lanes 7 and 8), were retained on the affinity gel. We conclude that either MLE does not interact with either MSL3 or MOF, or any interaction could not be detected by using this approach. Figure 3.FLAG affinity chromatography of FLAG-tagged MSL1–MOF complexes. Protein extracts were prepared from transformant flies that co-overexpressed MOF and either FLAG-MSL1 (lanes 1 and 2), FΔ84 (lanes 3 and 4), FΔ84ΔC* (lanes 5 and 6) or FC (lanes 7 and 8). Western blots containing either unpurified extract (E; lanes 1, 3, 5 and 7) or FLAG affinity-purified protein (P; lanes 2, 4, 6 and 8) were incubated with either anti-MSL1 (A) or anti-MOF (B) primary antibodies as described in the legend to Figure 2. (C) Silver stain of affinity-purified proteins Download figure Download PowerPoint Figure 4.FLAG affinity chromatography of FLAG-tagged MSL1–MSL3 complexes. Protein extracts were prepared from transformant flies that co-overexpressed MSL3 and either FLAG MSL1 (lanes 1 and 2), FΔ84 (lanes 3 and 4), FΔ84ΔC* (lanes 5 and 6) or FC (lanes 7 and 8). Western blots containing either unpurified extract (E; lanes 1, 3, 5 and 7) or FLAG affinity-purified protein (P; lanes 2, 4, 6 and 8) were incubated with either anti-MSL1 (A) or anti-MSL3 (B) primary antibodies as described in the legend to Figure 2. Download figure Download PowerPoint Figure 5.FLAG affinity chromatography of FLAG-tagged MSL1 co-expressed with MLE. Protein extracts were prepared from transformant flies that co-overexpressed MLE and either FΔ84 (lanes 3 and 4), FC (lanes 5 and 6) or FC, MSL3 and MOF (lanes 7 and 8). Protein extract was also prepared from a line that overexpressed MLE alone (lanes 1 and 2). Western blots containing either unpurified extract (E; lanes 1, 3, 5 and 7) or FLAG affinity-purified protein (P; lanes 2, 4, 6 and 8) were incubated with either anti-MSL1 (A) or anti-MLE (B) primary antibodies as described in the legend to Figure 2. Download figure Download PowerPoint To confirm the interaction between the C-terminal domain of MSL1 and MOF by an alternative method, we prepared GST–MOF fusion protein in Escherichia coli. The fusion protein was mixed with crude fly extracts from transformant lines expressing either MSL1 or one of the truncated versions of MSL1. As a control, we also incubated GST with each of the fly extracts. The protein mixes were then applied to glutathione–Sepharose and bound protein eluted with excess glutathione. MSL1 co-purified with GST–MOF but not with GST (Figure 6). This result confirms that MSL1 and MOF interact. The Δ84 (which includes the C-terminal domain) and FC proteins also co-purify specifically with GST–MOF over the glutathione affinity column (Figure 6). However, the Δ84ΔC* and MID proteins do not co-purify with GST–MOF (Figure 6). These results confirm that it is the C-terminal domain of MSL1 that interacts with MOF. Figure 6.Glutathione affinity chromatography of GST–MOF–MSL1 complexes. Fly extracts (E) from transformant lines that had been heat shocked to induce protein synthesis were incubated with glutathione–Sepharose beads containing either bound GST (G) or GST–MOF (GM). Bound proteins were eluted with glutathione. An aliquot of each sample was fractionated by SDS–PAGE, transferred to a nitrocellulose membrane, then incubated with anti-MSL1 antibody. The amount loaded on the input lanes corresponds to ∼7% of the material applied to the glutathione affinity beads. The band at 68 kDa seen in all panels is an E.coli protein that co-purifies with GST–MOF and reacts with the anti-MSL1 antibody. Elution of GST and GST–MOF was confirmed by probing identical membranes with anti-GST antibody (Sigma) (data not shown). Download figure Download PowerPoint To confirm the interaction between MSL3 and the C-terminal domain of MSL1, we generated transformant lines that express a haemagglutinin (HA) epitope-tagged form of MSL3 following a heat shock. The hsp·HAmsl3 lines were crossed with hsp·msl1, FΔ84ΔC* or FC lines and the offspring heat shocked prior to homogenization to induce MSL1 and HA·MSL3 synthesis. The crude fly extracts were incubated with high affinity HA antibody and immune complexes precipitated using protein G–agarose. HA-tagged MSL3 was precipitated efficiently by the HA antibody (Figure 7A). MSL1 and FC but not FΔ84ΔC* co-precipitated with HA·MSL3 (Figure 7B). These results confirm that the C-terminal domain of MSL1 associates with MSL3. Figure 7.MSL1 co-immunoprecipitates with HA-tagged MSL3. Protein extracts were prepared from transformant flies that co-overexpressed HA·MSL3 and either MSL1 (lanes 1, 2 and 3), FΔ84ΔC* (lanes 4, 5 and 6) or FC (lanes 7, 8 and 9). Aliquots of either unpurified extracts (E; lanes 1, 4 and 7), protein purified by incubation with protein G beads plus anti-HA antibody (+HA; lanes 2, 5 and 8) or protein precipitated by protein G beads alone (−HA; lanes 3, 6 and 9) were separated by SDS–PAGE and transferred to nitrocellulose membranes. The amount loaded on the extract lanes corresponds to ∼4% of the material incubated with protein G beads. Western blots were incubated with either anti-HA (A) or anti-MSL1 (B) primary antibodies. Download figure Download PowerPoint Since all of the above affinity purifications of MSL1–MSL complexes were from crude fly extracts, it is possible that the interactions between MSL1 and the other MSLs are not direct. To test this possibility, we performed in vitro translations with MSL1 C-terminal domain, HA·MSL3 and HA·MOF RNA templates. The [35S]methionine-labelled proteins were mixed and immunoprecipitated with anti-HA antibody (Figure 8). We found that C co-immunoprecipitated with HA·MSL3 but not HA·MOF (Figure 8). These experiments show that the C-terminal domain interacts directly with MSL3 but that the interaction with MOF requires either another factor present in fly extracts or post-translational modification of MSL1 or MOF. We favour the latter since a silver stain of FLAG affinity-purified FC–MOF complex separated by SDS–PAGE shows only two main bands corresponding to the sizes expected for FC and MOF (Figure 3). Figure 8.In vitro translated MSL1 C-terminal domain co-immunoprecipitates with in vitro translated HA·MSL3 but not with HA·MOF. In vitro translation reactions were carried out with RNA templates for HA·MOF (lane 1), MSL1 C-terminal domain (A, lane 4; B, lane 1) or HA·MSL3 (A, lane 7; B, lane 2) in the presence of [35S]methionine. C was mixed with either HA·MOF (A, lane 2) HA·MSL3 (A, lane 5; B, lane 5) or both (A, lane 6), and immunoprecipitated with anti-HA antibody and protein G beads. Proteins were separated by SDS–PAGE and either exposed to X-ray film (A) or transferred to a nitrocellulose membrane and incubated with anti-MSL1 antibody (B). The amount loaded on the translated protein lanes (T) corresponds to ∼5–10% of the protein that was mixed with anti-HA antibody and protein G beads (P). C co-immunoprecipitated with HA·MSL3 (A and B, lane 5) but not with HA·MOF (A, lane 2). Download figure Download PowerPoint The C-terminal domain of MSL1 contains a region that is high in Ser, Thr and Pro. Not surprisingly, a FASTA homology search of the protein database with the C-terminal domain amino acid sequence identified a number of proteins with similarity restricted to the Ser-, Thr- and Pro-rich region. However, both mouse and human CBP showed similarity across essentially the entire C-terminal domain (24% identity, 58% similarity to amino acids 863–1117 of mouse CBP; 23% identity and 58% similarity to amino acids 861–1116 of human CBP). A comparison of mouse CBP with Drosophila CBP (Akimaru et al., 1997) showed that, with the exception of the start of the bromodomain, the MSL1-similar region of mouse CBP is not well conserved in Drosophila CBP (28% identity to amino acids 1356–1690 of Drosophila CBP, 18 gaps in the alignment). Th
DA - 2000/1/4/
PY - 2000/1/4/
DO - 10.1093/emboj/19.1.144
VL - 19
IS - 1
SP - 144-155
OP -
SN - 1460-2075
UR - http://dx.doi.org/10.1093/emboj/19.1.144
DB - Crossref
ER -
TY - JOUR
TI - MSL1 plays a central role in assembly of the MSL complex, essential for dosage compensation in Drosophila
AU - Scott, Maxwell J
AU - Pan, Lewis L
AU - Cleland, Sheralee B
AU - Knox, Andrea L
AU - Heinrich, Jörg
T2 - The EMBO journal
DA - 2000///
PY - 2000///
VL - 19
IS - 1
SP - 144-155
ER -
TY - JOUR
TI - A repressible female-specific lethal genetic system for making transgenic insect strains suitable for a sterile-release program
AU - Heinrich, Jörg C.
AU - Scott, Maxwell J.
T2 - Proceedings of the National Academy of Sciences
AB - We have developed a tetracycline-repressible female-specific lethal genetic system in the vinegar fly Drosophila melanogaster. One component of the system is the tetracycline-controlled transactivator gene under the control of the fat body and female-specific transcription enhancer from the yolk protein 1 gene. The other component consists of the proapoptotic gene hid under the control of a tetracycline-responsive element. Males and females of a strain carrying both components are viable on medium supplemented with tetracycline, but only males survive on normal medium. A strain with such properties would be ideal for a sterile-insect release program, which is most effective when only males are released in the field.
DA - 2000/7/11/
PY - 2000/7/11/
DO - 10.1073/pnas.140142697
VL - 97
IS - 15
SP - 8229-8232
J2 - Proc. Natl. Acad. Sci. U.S.A.
LA - en
OP -
SN - 0027-8424 1091-6490
UR - http://dx.doi.org/10.1073/pnas.140142697
DB - Crossref
ER -
TY - CHAP
TI - Management of pesticidal crops
AU - Andow, D.A.
T2 - Biological resource management: Connecting science and policy
A2 - Balazs, E.
A2 - Galante, E.
A2 - Lynch, J.M.
A2 - Schepers, J.S.
A2 - Toutant, J.-P.
A2 - Werner, D.
A2 - Werry, P.A.Th J.
PY - 2000///
SP - 265–276
PB - Springer Verlag
ER -
TY - CONF
TI - Survival of Helicoverpa zea on Bt sweet corn
AU - Venette, R.C.
AU - O'Rourke, P.K.
AU - Hutchison, W.D.
AU - Burkness, E.C.
AU - Andow, D.A.
T2 - Beltway Cotton Conference
C2 - 2000///
C3 - Proceeding of the Beltway Cotton Conference
DA - 2000///
PY - 2000///
VL - 2
SP - 1058–1060
ER -
TY - CONF
TI - Resistance management for Bt corn: Progress and challenges to consensus in U.S. policy
AU - Hutchison, W.D.
AU - Andow, D.A.
T2 - 5th International symposium on biosafety results of field tests of genetically modified plants and microorganisms
A2 - Schiemann, J.
C2 - 2000///
C3 - Proceedings of 5th International symposium on biosafety results of field tests of genetically modified plants and microorganisms
CY - Braunschweig, Germany
DA - 2000///
PY - 1998/9/6/
SP - 231–238
PB - Parey Buchverlag
ER -
TY - NEWS
TI - Adaptive resistance management
T2 - Resistant Pest Management Newsletter
PY - 2000///
VL - 11
SP - 8
ER -
TY - JOUR
TI - Frequency of Resistance to Bacillus thuringiensis Toxin Cry1Ab in an Iowa Population of European Corn Borer (Lepidoptera: Crambidae)
AU - Andow, D. A.
AU - Olson, D. M.
AU - Hellmich, R. L.
AU - Alstad, D. N.
AU - Hutchison, W. D.
T2 - Journal of Economic Entomology
AB - The refuge plus high-dose strategy for resistance management assumes that the frequency of resistance alleles is low. We used an F2 screen to estimate the frequency of resistance to transgenic corn that produces Bacillus thuringiensis Berliner Cry1Ab toxin (Bt corn) in an Iowa population of European corn borer, Ostrinia nubilalis (Hübner). We also proposed a modification to the statistical analysis of the F2 screen that extends its application for nonuniform prior distributions and for repeated sampling of a single population. Based on a sample of 188 isofemale lines derived from females caught at light traps during the 2nd flight of 1997, we show with 95% confidence that the frequency of resistance to Bt corn was <3.9 x 10(-3) in this Iowa population. These results provide weak evidence that the refuge plus high-dose strategy may be effective for managing resistance in O. nubilalis to Bt corn. Partial resistance to Cry1Ab toxin was found commonly. The 95% CI for the frequency of partial resistance were [8.2 x 10(-4), 9.4 x 10(-3)] for the Iowa population. Variable costs of the method were 14.90 dollars per isofemale line, which was a reduction of 25% compared with our initial estimate.
DA - 2000/2/1/
PY - 2000/2/1/
DO - 10.1603/0022-0493-93.1.26
VL - 93
IS - 1
SP - 26-30
J2 - ec
LA - en
OP -
SN - 0022-0493 0022-0493
UR - http://dx.doi.org/10.1603/0022-0493-93.1.26
DB - Crossref
ER -
TY - JOUR
TI - An In-Field Screen for Early Detection and Monitoring of Insect Resistance to Bacillus thuringiensis in Transgenic Crops
AU - Venette, Robert C.
AU - Hutchison, W. D.
AU - Andow, D. A.
T2 - Journal of Economic Entomology
AB - We present a field-based approach to detect and monitor insects with resistance to insecticidal toxins produced by transgenic plants. Our objective is to estimate the phenotypic frequency of resistance in a population by relating the densities of insects on genetically transformed plants to densities on nontransformed plants. We focus on European corn borer, Ostrinia nubilalis (Hübner), in sweet corn, Zea mays L., expressing Cry1Ab from Bacillus thuringiensis subsp. kurstaki Berliner to illustrate principles underlying the method. The probability of detecting one or more rare, resistant larvae depends on sample size, the density of larvae on nontransformed plants, and an assumed frequency of resistant phenotypes in a given population. Probability of detection increases with increases in sample size, background density, or the frequency of resistant individuals. Following binomial probability theory, if a frequency of 10(-4) is expected, 10(3)-10(4) samples must be collected from a B. thuringiensis (Bt) crop to have at least a 95% probability of locating one or more resistant larvae. In-field screens using transgenic crops have several advantages over traditional laboratory-based methods, including exposure to a large number of feral insects, discrimination of resistant individuals based on Bt dosages expressed in the field, incorporation of natural and Bt-induced mortality factors, simultaneous monitoring for more than one insect species, and ease of use. The approach is amenable to field survey crews working in research, extension, and within the seed corn industry. Estimates of the phenotypic frequency of resistance from the in-field screen can be useful for estimating initial frequency of resistant alleles. Bayesian statistical methods are outlined to estimate phenotype frequencies, allele frequencies, and associated confidence intervals from field data. Results of the approach are discussed relative to existing complementary methods currently available for O. nubilalis and corn earworm, Helicoverpa zea (Boddie).
DA - 2000/8/1/
PY - 2000/8/1/
DO - 10.1603/0022-0493-93.4.1055
VL - 93
IS - 4
SP - 1055-1064
J2 - ec
LA - en
OP -
SN - 0022-0493 0022-0493
UR - http://dx.doi.org/10.1603/0022-0493-93.4.1055
DB - Crossref
ER -
TY - JOUR
TI - Provenance variation and provenance-site interaction in Pinus brutia TEN.: Consequences on the defining of breeding zones
AU - Isik, F.
AU - Keskin, S.
AU - McKeand, S.
T2 - Silvae Genetica
DA - 2000///
PY - 2000///
VL - 49
IS - 4-5
SP - 213–223
ER -
TY - CONF
TI - Expression and inheritance of a transgene for salinity tolerance in tomato
AU - Panthee, D.R.
AU - Wetten, A.
AU - Caligari, P.D.S.
T2 - 3rd International Conference on Biotechnology and Biodiversity
C2 - 2000///
C3 - 3rd International Conference on Biotechnology and Biodiversity
CY - Kathmandu, Nepal
DA - 2000///
PY - 2000///
SP - 14–16
ER -
TY - JOUR
TI - Identification and Characterization of a cDNA Encoding Cytochrome P450 3A from the Fresh Water Teleost Medaka (Oryzias latipes)
AU - Kullman, Seth W.
AU - Hamm, Jonathan T.
AU - Hinton, David E.
T2 - Archives of Biochemistry and Biophysics
AB - A new member of the CYP3A gene family has been cloned from the teleost fish medaka (Oryzias latipes) by reverse-transcriptase polymerase chain reaction (RT-PCR). Degenerate primers homologous to highly conserved regions of known CYP3A sequences were used for initial RT-PCRs. Individual PCR products were cloned, sequenced, and identified as those belonging to the cytochrome P450 superfamily based on amino acid sequence similarity and the presence of the highly conserved heme-binding region. PCR products were subsequently used as probes to screen a complementary DNA library. A full-length cDNA clone was identified containing a 1758-base-pair (bp) insert with an open reading frame encoding a single peptide of 500 amino acids. Comparisons of the deduced amino acid sequence to other known cytochrome P450 sequences indicate that this gene product is most similar to the CYP3A gene family and has been designated as CYP3A38 by the cytochrome P450 nomenclature committee. Northern blot analysis identified two abundant CYP3A related transcripts in liver of both male and female adults and demonstrated quantitative differences in abundance according to gender. Similarly, Western blot analysis demonstrated the presence of two abundant cytochrome P450 related proteins in liver of both male and female adults. These results suggests that O. latipes contains multiple forms of CYP3A. Heterologous expression of CYP3A38 cDNA in HEK 293 cells produced a single protein that was reactive with anti-scup P450A (CYP3A) polyclonal antibody. Microsomes of HEK 293 cells expressing recombinant CYP3A38 protein actively catalyzed the hydroxylation of testosterone.
DA - 2000/8//
PY - 2000/8//
DO - 10.1006/abbi.2000.1904
VL - 380
IS - 1
SP - 29-38
J2 - Archives of Biochemistry and Biophysics
LA - en
OP -
SN - 0003-9861
UR - http://dx.doi.org/10.1006/abbi.2000.1904
DB - Crossref
KW - medaka
KW - cytochrome P450
KW - CYP3A
KW - steroid metabolism
ER -
TY - SOUND
TI - A genome scan to identify QTL affecting economically important traits in dairy cattle
AU - Merrill, M.S.
DA - 2000/12//
PY - 2000/12//
ER -
TY - JOUR
TI - Movements of Two Experimentally Displaced Brown Treecreepers Ctimacteris picumnus in a Matrix of Woodland and Pasture
AU - Cooper, C.B.
T2 - Corella
DA - 2000///
PY - 2000///
VL - 26
IS - 4
SP - 110–113
ER -
TY - JOUR
TI - Comparative map alignment of BTA27 and HSA4 and 8 to identify conserved segments of genome containing fat deposition QTL
AU - Sonstegard, Tad S.
AU - Garrett, Wes M.
AU - Ashwell, Melissa S.
AU - Bennett, Gary L.
AU - Kappes, Steven M.
AU - Van Tassell, Curtis P.
T2 - Mammalian Genome
AB - Quantitative trait loci (QTL) associated with fat deposition have been identified on bovine Chromosome 27 (BTA27) in two different cattle populations. To generate more informative markers for verification and refinement of these QTL-containing intervals, we initiated construction of a BTA27 comparative map. Fourteen genes were selected for mapping based on previously identified regions of conservation between the cattle and human genomes. Markers were developed from the bovine orthologs of genes found on human Chromosomes 1 (HSA1), 4, 8, and 14. Twelve genes were mapped on the bovine linkage map by using markers associated with single nucleotide polymorphisms or microsatellites. Seven of these genes were also anchored to the physical map by assignment of fluorescence in situ hybridization probes. The remaining two genes not associated with an identifiable polymorphism were assigned only to the physical map. In all, seven genes were mapped to BTA27. Map information generated from the other seven genes not syntenic with BTA27 refined the breakpoint locations of conserved segments between species and revealed three areas of disagreement with the previous comparative map. Consequently, portions of HSA1 and 14 are not conserved on BTA27, and a previously undefined conserved segment corresponding to HSA8p22 was identified near the pericentromeric region of BTA8. These results show that BTA27 contains two conserved segments corresponding to HSA8p, which are separated by a segment corresponding to HSA4q. Comparative map alignment strongly suggests the conserved segment orthologous to HSA8p21-q11 contains QTL for fat deposition in cattle.
DA - 2000/8//
PY - 2000/8//
DO - 10.1007/s003350010130
VL - 11
IS - 8
SP - 682-688
J2 - Mammalian Genome
LA - en
OP -
SN - 0938-8990 1432-1777
UR - http://dx.doi.org/10.1007/s003350010130
DB - Crossref
ER -
TY - JOUR
TI - Detection of Putative Loci Affecting Milk, Health, and Conformation Traits in a US Holstein Population Using 105 Microsatellite Markers
AU - Van Tassell, C.P.
AU - Ashwell, M.S.
AU - Sonstegard, T.S.
T2 - Journal of Dairy Science
AB - Quantitative trait loci affecting milk yield, health, and conformation traits were studied for eight large US Holstein grandsire families by using the granddaughter design. A total of 105 microsatellite markers, located throughout the bovine genome, were selected for the scan. The data analyzed include genotypes for 35 markers in eight families not previously reported and genotypes for 70 markers reported previously in seven of those families. Analyses of markers previously reported were updated. Effects of marker alleles were analyzed for 38 traits, including traits for milk production, somatic cell score, productive life, conformation, calving ease, and 16 canonical traits derived from conformation and production traits. Permutation tests were used to calculate empirical trait-wise error rates. A trait-wise critical value of P = 0.1 was used to determine significance. Eight putative quantitative trait loci associated with 7 of the 35 new markers were identified within specific families. Two of these markers were associated with differences in strength and rump angle on chromosomes 4 and 9, respectively. Different markers were associated with protein percentage, milk yield, and somatic cell score on chromosomes 6, 7, and 10 in different families. Differences in the canonically transformed traits were associated with markers on chromosomes 5, 6, and 9. Additional marker-trait combinations were identified in the across-family tests, including effects on chromosomes 3, 4, and 9 for protein percentage, body depth, and canonical conformation traits, respectively. Additional markers are being added to allow interval analysis for putative quantitative trait loci that have been identified and to increase marker density.
DA - 2000/8//
PY - 2000/8//
DO - 10.3168/jds.s0022-0302(00)75058-2
VL - 83
IS - 8
SP - 1865-1872
J2 - Journal of Dairy Science
LA - en
OP -
SN - 0022-0302
UR - http://dx.doi.org/10.3168/jds.s0022-0302(00)75058-2
DB - Crossref
KW - quantitative trait loci
KW - microsatellite markers
KW - conformation traits
KW - milk production traits
ER -
TY - JOUR
TI - Surveying determinants of protein structure designability across different energy models and amino-acid alphabets: A consensus
T2 - The Journal of Chemical Physics
AB - A variety of analytical and computational models have been proposed to answer the question of why some protein structures are more “designable” (i.e., have more sequences folding into them) than others. One class of analytical and statistical-mechanical models has approached the designability problem from a thermodynamic viewpoint. These models highlighted specific structural features important for increased designability. Furthermore, designability was shown to be inherently related to thermodynamically relevant energetic measures of protein folding, such as the foldability ℱ and energy gap Δ10. However, many of these models have been done within a very narrow focus: Namely, pair–contact interactions and two-letter amino-acid alphabets. Recently, two-letter amino-acid alphabets for pair–contact models have been shown to contain designability artifacts which disappear for larger-letter amino-acid alphabets. In addition, a solvation model was demonstrated to give identical designability results to previous two-letter amino-acid alphabet pair–contact models. In light of these discordant results, this report synthesizes a broad consensus regarding the relationship between specific structural features, foldability ℱ, energy gap Δ10, and structure designability for different energy models (pair–contact vs solvation) across a wide range of amino-acid alphabets. We also propose a novel measure Zdk which is shown to be well correlated to designability. Finally, we conclusively demonstrate that two-letter amino-acid alphabets for pair–contact models appear to be solvation models in disguise.
DA - 2000///
PY - 2000///
DO - 10.1063/1.480893
UR - https://publons.com/publon/2047266/
ER -
TY - CONF
TI - Complicated Urinary Tract Infections In 100 Dogs: A Retrospective Study
AU - Seguin, A.
AU - Vaden, S.
AU - Levine, J.
AU - Stone, E.
T2 - American College of Veterinary Internal Medicine
C2 - 2000/5//
CY - Seattle, Washington
DA - 2000/5//
PY - 2000/5//
ER -
TY - SOUND
TI - Adult and Kitten Survival Time of Feral Cats in Managed Colonies in Randolph County
AU - Nutter, F.B.
AU - Levine, J.F.
AU - Stoskopf, M.K.
DA - 2000/6//
PY - 2000/6//
ER -
TY - CONF
TI - Prevalence of Bacterial Foodborne Pathogens in Shellfish
AU - Tlamka, B
AU - Pitts, T
AU - Levine, Jf
AU - French, Je
AU - Mare, Cj
AU - Joens, La
T2 - Conference of Research Workers in Animal Diseases (CRWAD)
C2 - 2000/12//
CY - Chicago, IL
DA - 2000/12//
PY - 2000/12//
ER -
TY - JOUR
TI - Characterization of extremely thermostable enzymatic breakers (α-1,6-galactosidase and β-1,4-mannanase) from the hyperthermophilic bacterium Thermotoga neapolitana 5068 for hydrolysis of guar gum
AU - McCutchen, Carol M.
AU - Duffaud, Guy D.
AU - Leduc, Pascal
AU - Petersen, Anja R. H.
AU - Tayal, Akash
AU - Khan, Saad A.
AU - Kelly, Robert M.
T2 - Biotechnology and Bioengineering
AB - An alpha-galactosidase and a beta-mannanase produced by the hyperthermophilic bacterium, Thermotoga neapolitana 5068 (TN5068), separately and together, were evaluated for their ability to hydrolyze guar gum in relation to viscosity reduction of guar-based hydraulic fracturing fluids used in oil and gas well stimulation. In such applications, premature guar gum hydrolysis at lower temperatures before the fracturing process is completed is undesirable, whereas thermostability and thermoactivity are advantageous. Hyperthermophilic enzymes presumably possess both characteristics. The purified alpha-galactosidase was found to have a temperature optimum of 100-105 degrees C with a half-life of 130 minutes at 90 degrees C and 3 min at 100 degrees C, while the purified beta-mannanase was found to have a temperature optimum of 91 degrees C and a half-life of 13h at this temperature and 35 min at 100 degrees C.These represent the most thermostable versions of these enzymes yet reported. At 25 degrees C, TN5068 culture supernatants, containing the two enzyme activities, reduced viscosity of a 0.7% (wt) guar gum solution by a factor of 1.4 after a 1.5-h incubation period and by a factor of 2.4 after 5 h. This is in contrast to a viscosity reduction of 100-fold after 1.5 h and 375-fold after 5 h for a commercial preparation of these enzymes from Aspergillus niger. In contrast, at 85 degrees C, the TN5068 enzymes reduced viscosity by 30-fold after 1.5 h and 100-fold after 5 h compared to a 2.5-fold reduction after 5 h for the control. The A. niger enzymes were less effective at 85 degrees C (1.6-fold reduction after 1.5 h and a 4.2-fold reduction after 5 h), presumably due to their thermal lability at this temperature. Furthermore, it was determined that the purified beta-mannanase alone can substantially reduce viscosity of guar solutions, while the alpha-galactosidase alone had limited viscosity reduction activity. However, the alpha-galactosidase appeared to minimize residual particulate matter when used in conjunction with the beta-mannanase. This could be the result of extensive hydrolysis of the alpha-1,6 linkages between mannose and galactose units in guar, allowing more extensive hydrolysis of the mannan chain by the beta-mannanase. The use of thermostable enzymatic breakers from hyperthermophiles in hydraulic fracturing could be used to improve well stimulation and oil and gas recovery.
DA - 2000/3/26/
PY - 2000/3/26/
DO - 10.1002/(sici)1097-0290(19961020)52:2<332::aid-bit13>3.0.co;2-l
VL - 52
IS - 2
SP - 332-339
J2 - Biotechnol. Bioeng.
LA - en
OP -
SN - 0006-3592 1097-0290
UR - http://dx.doi.org/10.1002/(sici)1097-0290(19961020)52:2<332::aid-bit13>3.0.co;2-l
DB - Crossref
KW - hyperthermophilic enzymes
KW - enzyme breakers
KW - hydraulic fracturing
KW - hydrolysis galactomannan
KW - guar gum
ER -
TY - JOUR
TI - Performance of ‘Gala’ apple on 18 dwarf rootstocks: A five year summary of the 1994 NC-140 dwarf rootstock trial
AU - Marini, R.P.
AU - Anderson, J.L.
AU - Autio, W.R.
AU - Barritt, B.H.
AU - Cline, J.
AU - Cowgill, W.P., Jr.
AU - Crassweller, R.M.
AU - Domoto, P.A.
AU - Ferree, D.C.
AU - Garner, J.
AU - Gaus, A.
AU - Greene, G.M.
AU - Hampson, C.
AU - Hirst, P.
AU - Kushad, M.M.
AU - Mielke, E.
AU - Mullins, C.A.
AU - Parker, M.
AU - Perry, R.L.
AU - Prive, J.P.
AU - Reighard, G.L.
AU - Robinson, T.
AU - Rom, C.R.
AU - Roper, T.
AU - Schupp, J.R.
AU - Stover, E.
AU - Unrath, R.
T2 - Journal of the American Pomological Society
DA - 2000///
PY - 2000///
VL - 54
IS - 2
SP - 92–107
ER -
TY - JOUR
TI - Performance of ‘Gala’ apple on four semi-dwarf rootstocks: A five year summary of the 1994 NC-140 semi-dwarf rootstock trial
AU - Marini, R.P.
AU - Anderson, J.L.
AU - Barritt, B.H.
AU - Brown, G.R.
AU - Cline, J.
AU - Cowgill, W.P., Jr.
AU - Domoto, P.A.
AU - Ferree, D.C.
AU - Garner, J.
AU - Greene, G.M.
AU - Hampson, C.
AU - Hirst, P.
AU - Kushad, M.M.
AU - Mielke, E.
AU - Mullins, C.A.
AU - Parker, M.
AU - Perry, R.L.
AU - Prive, J.P.
AU - Reighard, G.L.
AU - Robinson, T.
AU - Rom, C.R.
AU - Roper, T.
AU - Schupp, J.R.
AU - Stover, E.
AU - Unrath, R.
T2 - Journal of the American Pomological Society
DA - 2000///
PY - 2000///
VL - 54
IS - 2
SP - 84–91
ER -
TY - JOUR
TI - Linkage inheritance among 6 genes in cucumber
AU - Liu, J.S.
AU - Wehner, T.C.
T2 - Hereditas (Beijing)
DA - 2000///
PY - 2000///
VL - 22
IS - 3
SP - 137–140
ER -
TY - JOUR
TI - Physical mapping of male fertility and meiotic drive quantitative trait loci in the mouse t complex using chromosome deficiencies
AU - Planchart, A.
AU - You, Y.
AU - Schimenti, J.C.
T2 - Genetics
DA - 2000///
PY - 2000///
VL - 155
IS - 2
SP - 803-812
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034084813&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Regulation of sucrose metabolism in higher plants: Localization and regulation of activity of key enzymes
AU - Winter, H.
AU - Huber, S.C.
T2 - Critical Reviews in Biochemistry and Molecular Biology
AB - Sucrose (Suc) plays a central role in plant growth and development. It is a major end product of photosynthesis and functions as a primary transport sugar and in some cases as a direct or indirect regulator of gene expression. Research during the last 2 decades has identified the pathways involved and which enzymes contribute to the control of flux. Availability of metabolites for Suc synthesis and 'demand' for products of sucrose degradation are important factors, but this review specifically focuses on the biosynthetic enzyme sucrose-phosphate synthase (SPS), and the degradative enzymes, sucrose synthase (SuSy), and the invertases. Recent progress has included the cloning of genes encoding these enzymes and the elucidation of posttranslational regulatory mechanisms. Protein phosphorylation is emerging as an important mechanism controlling SPS activity in response to various environmental and endogenous signals. In terms of Suc degradation, invertase-catalyzed hydrolysis generally has been associated with cell expansion, whereas SuSy-catalyzed metabolism has been linked with biosynthetic processes (e.g., cell wall or storage products). Recent results indicate that SuSy may be localized in multiple cellular compartments: (1) as a soluble enzyme in the cytosol (as traditionally assumed); (2) associated with the plasma membrane; and (3) associated with the actin cytoskeleton. Phosphorylation of SuSy has been shown to occur and may be one of the factors controlling localization of the enzyme. The purpose of this review is to summarize some of the recent developments relating to regulation of activity and localization of key enzymes involved in sucrose metabolism in plants.
DA - 2000///
PY - 2000///
DO - 10.1080/10409230008984165
VL - 35
IS - 4
SP - 253-289
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033829914&partnerID=MN8TOARS
KW - actin cytoskeleton
KW - 14-3-3 proteins
KW - invertase
KW - SNF1 protein kinase
KW - CDPK
KW - regulatory protein phosphorylation
KW - sucrose-phosphate synthase
KW - sucrose-sensing
KW - sucrose synthase
KW - translocation
ER -
TY - JOUR
TI - Regulation of sucrose metabolism in higher plants: Localization and regulation of activity of key enzymes
AU - Winter, H.
AU - Huber, S.C.
T2 - Critical Reviews in Plant Sciences
AB - Sucrose (Suc) plays a central role in plant growth and development. It is a major end product of photosynthesis and functions as a primary transport sugar and in some cases as a direct or indirect regulator of gene expression. Research during the last 2 decades has identified the pathways involved and which enzymes contribute to the control of flux. Availability of metabolites for Suc synthesis and ‘demand’ for products of sucrose degradation are important factors, but this review specifically focuses on the biosynthetic enzyme sucrose-phosphate synthase (SPS), and the degradative enzymes, sucrose synthase (SuSy), and the invertases. Recent progress has included the cloning of genes encoding these enzymes and the elucidation of posttranslational regulatory mechanisms. Protein phosphorylation is emerging as an important mechanism controlling SPS activity in response to various environmental and endogenous signals. In terms of Suc degradation, invertase-catalyzed hydrolysis generally has been associated with cell expansion, whereas SuSy-catalyzed metabolism has been linked with biosynthetic processes (e.g., cell wall or storage products). Recent results indicate that SuSy may be localized in multiple cellular compartments: (1) as a soluble enzyme in the cytosol (as traditionally assumed); (2) associated with the plasma membrane; and (3) associated with the actin cytoskel-eton. Phosphorylation of SuSy has been shown to occur and may be one of the factors controlling localization of the enzyme. The purpose of this review is to summarize some of the recent developments relating to regulation of activity and localization of key enzymes involved in sucrose metabolism in plants.
DA - 2000///
PY - 2000///
DO - 10.1080/07352680091139178
VL - 19
IS - 1
SP - 31-67
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033984161&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Quantitative analysis of leptin mRNA using competitive reverse transcription polymerase chain reaction and capillary electrophoresis with laser-induced fluorescence detection
AU - Richards, Mark P
AU - Ashwell, Christopher M
AU - McMurtry, John P
T2 - ELECTROPHORESIS: An International Journal
DA - 2000///
PY - 2000///
VL - 21
IS - 4
SP - 792-798
ER -
TY - JOUR
TI - PROTEIN SYNTHESIS, POST-TRANSLATION MODIFICATION, AND DEGRADATION-The role of the membrane-spanning domain of type I signal peptidases in substrate cleavage site selection.
AU - Carlos, Joseph L
AU - Paetzel, Mark
AU - Brubaker, Greg
AU - Karla, Andrew
AU - Ashwell, Christopher M
AU - Lively, Mark O
AU - Cao, Guoqing
AU - Bullinger, Patrick
AU - Dalbey, Ross E
T2 - Journal of Biological Chemistry
DA - 2000///
PY - 2000///
VL - 275
IS - 49
SP - 38813-38822
ER -
TY - JOUR
TI - The role of the membrane-spanning domain of type I signal peptidases in substrate cleavage site selection
AU - Carlos, Joseph L
AU - Paetzel, Mark
AU - Brubaker, Greg
AU - Karla, Andrew
AU - Ashwell, Christopher M
AU - Lively, Mark O
AU - Cao, Guoqing
AU - Bullinger, Patrick
AU - Dalbey, Ross E
T2 - Journal of Biological Chemistry
DA - 2000///
PY - 2000///
VL - 275
IS - 49
SP - 38813-38822
ER -
TY - JOUR
TI - Leptin-induced decrease in food intake in chickens
AU - Denbow, D Michael
AU - Meade, Sharonda
AU - Robertson, Adam
AU - McMurtry, John P
AU - Richards, Mark
AU - Ashwell, Chris
T2 - Physiology & Behavior
DA - 2000///
PY - 2000///
VL - 69
IS - 3
SP - 359-362
ER -
TY - JOUR
TI - Design and application of a polyclonal peptide antiserum for the universal detection of leptin protein
AU - Richards, Mark P
AU - Caperna, Thomas J
AU - Elsasser, Theodore H
AU - Ashwell, Christopher M
AU - McMurtry, John P
T2 - Journal of biochemical and biophysical methods
DA - 2000///
PY - 2000///
VL - 45
IS - 2
SP - 147-156
ER -
TY - BOOK
TI - Genetically Modified Pest-Protected Plants: Science and Regulation
DA - 2000/8/23/
PY - 2000/8/23/
DO - 10.17226/9795
PB - National Academies Press
SN - 9780309069304
UR - http://dx.doi.org/10.17226/9795
ER -
TY - BOOK
TI - Bioinformatics: Converting Data to Knowledge
DA - 2000/11/1/
PY - 2000/11/1/
DO - 10.17226/9990
PB - National Academies Press
SN - 9780309072564
UR - http://dx.doi.org/10.17226/9990
ER -
TY - JOUR
TI - Recurrent selection in oat for adaptation to diverse environments
T2 - Euphytica
DA - 2000///
PY - 2000///
DO - 10.1023/A:1003933421378
VL - 113
IS - 3
SP - 195-205
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034076602&partnerID=MN8TOARS
KW - Avena
KW - genetic correlation
KW - genotype-environment interaction
KW - stability
ER -
TY - CHAP
TI - Update: Infectious Endocarditis
AU - DeFrancesco, T.C.
T2 - Kirk’s Current Veterinary Therapy XIII
A2 - Bonagura, J.D.
A2 - Kirk, R.W.
PY - 2000///
SP - 768–771
PB - WB Saunders
ER -
TY - CHAP
TI - Cardiac Emergencies, Hypertension, Electrocution, and Exam of the Cardiovascular System
AU - DeFrancesco, T.C.
T2 - Kirk and Bistner's handbook of veterinary procedures and emergency treatment
A2 - Bistner, S.
A2 - Ford, R.B.
A2 - Raffe, M.R.
A2 - Kirk, R.W.
PY - 2000///
ET - 7th
SP - 54–74, 282–313
PB - WB Saunders
ER -
TY - JOUR
TI - A highly polymorphic marker identified in intron 15 of the feline cardiac troponin T gene by SSCP analysis
AU - Magnon, A.L.
AU - Meurs, K.M.
AU - Kittleson, M.D.
AU - Ware, W.A.
T2 - Animal Genetics
DA - 2000///
PY - 2000///
VL - 31
SP - 236 –237
ER -
TY - JOUR
TI - The identification of nine polymorphisms identified within the head region of feline Beta Myosin heavy chain gene
AU - Meurs, K.M.
AU - Kittleson, M.D.
AU - Ware, W.A.
AU - Miller, M.W.
T2 - Animal Genetics
DA - 2000///
PY - 2000///
VL - 31
SP - 231
ER -
TY - CHAP
TI - Update on Doberman pinscher cardiomyopathy
AU - Calvert, C.
AU - Meurs, K.M.
T2 - Current Veterinary Therapy (Small Animal Practice) XIII
PY - 2000///
SP - 756–760
PB - WB Saunders
ER -
TY - JOUR
TI -
AU - Xie, Deyu
AU - Wang, Lianhui
AU - Ye, Hechun
AU - Li, Guofeng
T2 - Plant Cell, Tissue and Organ Culture
DA - 2000///
PY - 2000///
DO - 10.1023/a:1006438919841
VL - 63
IS - 2
SP - 161-166
OP -
SN - 0167-6857
UR - http://dx.doi.org/10.1023/a:1006438919841
DB - Crossref
KW - Artemisia annua
KW - artemisinin
KW - hairy root culture
KW - stigmasterol
ER -
TY - JOUR
TI - Evaluation of Sweetpotato Cultivars to Root-knot Nematodes
AU - Cervantes, J.C.
AU - Davis, D.L.
AU - Yencho, G.C.
T2 - HortScience
AB - This study was conducted to determine whether the type of pot used for the evaluation affected the resistance response of the sweetpotato plants, and to assess the resistance response to different root-knot nematode species. Five sweetpotato [ Ipomoea batatas (L.) Lam] cultivars, `Beauregard', `Exce'l, `Jewel', `Hernandez', and `Porto Rico', were screened for M. incognita (race 3), Meloidogyne arenaria (race 2), and M. javanica , in both 10-cm-side, square pots and 4-cm-diameter, cone pots. Gall index, necrosis index, and number of nematode eggs per gram of root were used to estimate nematode-resistance reaction. Mean of all indices between the 2 pot types were not significantly different (α = 0.05). Gall and necrosis indices were not correlated in any of the cultivars. Resistance response depended on cultivars and nematode species for all variables analyzed. `Beauregard' was the most susceptible to Meloidogyne . `Hernandez' and `Excel' were found to be the most resistant cultivars to the Meloidogyne species.
DA - 2000/7//
PY - 2000/7//
DO - 10.21273/hortsci.35.4.569e
VL - 35
IS - 4
SP - 569E-569d
ER -
TY - JOUR
TI - Inositol signaling and plant growth
AU - Stevenson, Jill M
AU - Perera, Imara Y
AU - Heilmann, Ingo
AU - Persson, Staffan
AU - Boss, Wendy F
T2 - Trends in Plant Science
AB - Living organisms have evolved to contain a wide variety of receptors and signaling pathways that are essential for their survival in a changing environment. Of these, the phosphoinositide pathway is one of the best conserved. The ability of the phosphoinositides to permeate both hydrophobic and hydrophilic environments, and their diverse functions within cells have contributed to their persistence in nature. In eukaryotes, phosphoinositides are essential metabolites as well as labile messengers that regulate cellular physiology while traveling within and between cells. The stereospecificity of the six hydroxyls on the inositol ring provides the basis for the functional diversity of the phosphorylated isomers that, in turn, generate a selective means of intracellular and intercellular communication for coordinating cell growth. Although such complexity presents a difficult challenge for bench scientists, it is ideal for the regulation of cellular functions in living organisms.
DA - 2000/6//
PY - 2000/6//
DO - 10.1016/s1360-1385(00)01652-6
VL - 5
IS - 6
SP - 252-258
J2 - Trends in Plant Science
LA - en
OP -
SN - 1360-1385
UR - http://dx.doi.org/10.1016/s1360-1385(00)01652-6
DB - Crossref
ER -
TY - JOUR
TI - Isolated trees as foci of diversity in active and fallow fields
AU - Dunn, R.R.
T2 - Biological Conservation
AB - As the percentage of forest converted to agroecosystems in the tropics rises, it becomes increasingly important to understand how biodiversity can be managed in these ecosystems. In this study, I tested the hypotheses that insect abundance and diversity are higher near isolated trees in crop fields than in the open and that the diversity and abundance of insects increases with the density of isolated trees. Ant species richness, ant abundance and beetle abundance per trap were higher near isolated trees than in the open. Isolated trees had less of an affect on beetle abundance in fallow than active fields. Ant species richness was positively correlated with tree size. Ant species richness per field, ant abundance and beetle abundance per field were not correlated with tree density or the condition of surrounding fields. These results indicate that isolated trees can play a role in determining the local distribution of ants and beetles in crop fields.
DA - 2000///
PY - 2000///
DO - 10.1016/S0006-3207(00)00025-2
VL - 95
IS - 3
SP - 317-321
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033924388&partnerID=MN8TOARS
KW - isolated trees
KW - biodiversity
KW - Ghana
KW - agroecosystem
KW - ants
KW - beetles
ER -
TY - JOUR
TI - Direct quantitation of rapid elimination of viral antigen-positive lymphocytes by antiviral CD8+ T cellsin vivo
AU - Barchet, Winfried
AU - Oehen, Stephan
AU - Klenerman, Paul
AU - Wodarz, Dominik
AU - Bocharov, Gennadii
AU - Lloyd, Alun L.
AU - Nowak, Martin A.
AU - Hengartner, Hans
AU - Zinkernagel, Rolf M.
AU - Ehl, Stephan
T2 - European Journal of Immunology
AB - Lysis of infected cells by CD8(+) T cells is an important mechanism for the control of virus infections, but remains difficult to quantify in vivo. Here, we study the elimination kinetics of viral antigen-positive lymphocytes by antiviral CD8(+) T cells using flow cytometry and mathematical analysis. In mice acutely infected with lymphocytic choriomeningitis virus, more than 99.99 % of target cells were eliminated each day, corresponding to a half-life of 1.4 h. Even in mice exposed to virus 300 days previously, and with no ex vivo killing activity, 84 % of the target cells were eliminated per day. Unexpectedly, the elimination kinetics of antigen-positive lymphocytes was not significantly impaired in mice deficient in either perforin-, CD95 ligand- or TNF-mediated cytotoxicity. For viruses with a particular tropism for lymphocytes, such as Epstein-Barr virus or HIV, our results illustrate how effectively CD8(+) T cell-mediated elimination of target cells can potentially contribute to virus control and immunosuppression.
DA - 2000/5//
PY - 2000/5//
DO - 10.1002/(SICI)1521-4141(200005)30:5<1356::AID-IMMU1356>3.0.CO;2-K
VL - 30
IS - 5
SP - 1356-1363
J2 - Eur. J. Immunol.
LA - en
OP -
SN - 0014-2980 1521-4141
UR - http://dx.doi.org/10.1002/(SICI)1521-4141(200005)30:5<1356::AID-IMMU1356>3.0.CO;2-K
DB - Crossref
KW - CD8(+) T cell
KW - virus
KW - cytotoxicity
KW - perforin
KW - CD95
ER -
TY - JOUR
TI - Molecular Screening by Polymerase Chain Reaction Detects Panleukopenia Virus DNA in Formalin-Fixed Hearts from Cats with Idiopathic Cardiomyopathy and Myocarditis
AU - Meurs, Kathryn M
AU - Fox, Philip R
AU - Magnon, Alexander L
AU - Liu, Si-Kwang
AU - Towbin, Jeffrey A
T2 - Cardiovascular Pathology
AB - Viral myocarditis has been suggested as an etiology for cardiomyopathy in several mammalian species. Myocarditis and idiopathic cardiomyopathy have been reported in the domestic cat, although a viral etiology has not been demonstrated. Because of the continuing interest in the potential relationship between viral myocarditis and cardiomyopathy, we evaluated hearts from cats with spontaneous, idiopathic cardiomyopathy for viral genomic material within myocytes by polymerase chain reaction, and for the presence of myocarditis by light microscopy. Thirty-one (31) formalin-fixed hearts from domestic cats who died of idiopathic cardiomyopathy were randomly selected from pathology archives. Seventeen (17) formalin-fixed hearts from healthy cats were similarly selected as normal controls. The polymerase chain reaction (PCR) was used to evaluate myocardial tissue for the presence of viral genome from feline panleukopenia virus, herpes virus, calici virus, and corona virus. Hearts were examined using light microscopy for histologic evidence of myocarditis according to the Dallas criteria. Panleukopenia virus was identified by PCR in 10 of 31 cats with cardiomyopathy but in none of the controls. Neither cardiomyopathic or control cats tested positive by PCR for herpes virus, calici virus, and corona virus. Myocarditis was detected by histologic examination in 18 of 31 cardiomyopathic cats and in none of 17 control cats. Myocarditis and or feline panleukopenia virus genome was detected in felines with idiopathic hypertrophic, dilated, and restrictive cardiomyopathy, suggesting a possible role of viral infection and inflammation in the pathogenesis of cardiomyopathy in this species.
DA - 2000/3//
PY - 2000/3//
DO - 10.1016/s1054-8807(00)00031-4
VL - 9
IS - 2
SP - 119-126
J2 - Cardiovascular Pathology
LA - en
OP -
SN - 1054-8807
UR - http://dx.doi.org/10.1016/s1054-8807(00)00031-4
DB - Crossref
ER -
TY - JOUR
TI - Arterial blood pressure measurement in a population of healthy geriatric dogs
AU - Meurs, KM
AU - Miller, MW
AU - Slater, MR
AU - Glaze, K
T2 - Journal of the American Animal Hospital Association
AB - The purpose of this study was to evaluate healthy geriatric dogs for the presence of systemic hypertension. Thirty-three geriatric dogs (i.e., dogs exceeding the geriatric age range for their weight group) and 22 control dogs (i.e., dogs less than six years of age) were evaluated by measuring blood pressure with an oscillometric monitor. Five consecutive blood pressure measurements were taken in each dog, averaged, and compared. Diastolic and mean blood pressure measurements were significantly lower in the geriatric group as compared to the control group. Systolic blood pressure measurements were not significantly different between the two groups. Systemic hypertension does not appear to be a common clinical problem in the healthy geriatric dog.
DA - 2000/11//
PY - 2000/11//
DO - 10.5326/15473317-36-6-497
VL - 36
IS - 6
SP - 497-500
J2 - Journal of the American Animal Hospital Association
LA - en
OP -
SN - 0587-2871 1547-3317
UR - http://dx.doi.org/10.5326/15473317-36-6-497
DB - Crossref
ER -
TY - JOUR
TI - Single nucleotide polymorphisms in intron 5 of the feline myosin regulatory light chain gene detected by SSCP analysis
AU - Magnon, A L
AU - Meurs, K M
AU - Kittleson, M D
AU - Ware, W A
T2 - Animal Genetics
AB - Recently, we published the mapping of the chicken leptin gene to a microchromosome. This work was done through PCR-SSCP analysis, using primers designed from a published sequence (, EMBL accession number AF012727), presenting 97% similarity to the mouse and 83% to the human leptin genes. This sequence was also published by another group and the primers were therefore supposed to be homologous ones. We have now sequenced our PCR product: although it was amplified with primers chosen from a chicken sequence, it is neither homologous to the published leptin sequence, nor to any other sequence in Genebank/EMBL databases. Therefore, the amplimer we have localised can not be considered as a part of the chicken leptin gene.
DA - 2000/8//
PY - 2000/8//
DO - 10.1046/j.1365-2052.2000.00620.x
VL - 31
IS - 4
SP - 281-282
J2 - Animal Genetics
LA - en
OP -
SN - 0268-9146 1365-2052
UR - http://dx.doi.org/10.1046/j.1365-2052.2000.00620.x
DB - Crossref
ER -
TY - JOUR
TI - Relationship between tissue-specific hydrocarbon profiles and lipid melting temperatures in the cockroach Blattella germanica
AU - YOUNG, HP
AU - LARABEE, JK
AU - GIBBS, AG
AU - SCHAL, C
T2 - JOURNAL OF CHEMICAL ECOLOGY
DA - 2000///
PY - 2000///
VL - 26
IS - 5
SP - 1245-1263
ER -
TY - JOUR
TI - Consentience on the necessity of Juvenile Hormone for vitellogenesis in the German cockroach - Reply
AU - HOLBROOK, GL
AU - BACHMANN, JA
AU - SCHAL, C
T2 - PHYSIOLOGICAL ENTOMOLOGY
DA - 2000///
PY - 2000///
VL - 25
IS - 3
SP - 208-210
ER -
TY - JOUR
TI - New frontiers in the study of dispersal and spatial analysis of epidemics caused by species in the genus Phytophthora
AU - Ristaino, Jean Beagle
AU - Gumpertz, Marcia L
T2 - Annual Review of Phytopathology
DA - 2000///
PY - 2000///
VL - 38
IS - 1
SP - 541-576
ER -
TY - JOUR
TI - BIOCHEMISTRY AND CELL BIOLOGY-Commercial Fungicide Formulations Induce In Vitro Oo-spore Formation and Phenotypic Change in Mating Type in Phytophthora infestans
AU - Groves, CT
AU - Ristaino, JB
T2 - Phytopathology
DA - 2000///
PY - 2000///
VL - 90
IS - 11
SP - 1201-1208
ER -
TY - JOUR
TI - ADVANCES IN TEMPERATURE PREDICTIVE MODELS FOR SOIL SOLARIZATION
AU - Ristaino, JB
AU - Perry, KB
AU - Wu, Y
T2 - FAO PLANT PRODUCTION AND PROTECTION PAPERS
DA - 2000///
PY - 2000///
SP - 463-471
ER -
TY - JOUR
TI - A history of research on the link between (micro) aggregates, soil biota and soil organic matter dynamics.
AU - Babalola, OA
AU - Adesodun, JK
AU - Olasantan, FO
AU - Adekunle, AF
AU - Aggelides, SM
AU - Londra, PA
AU - Akintokun, AK
AU - Akande, GA
AU - Akintokun, PO
AU - Popoola, TOS
AU - others
T2 - International Journal of Soil Science
DA - 2000///
PY - 2000///
VL - 7
IS - 1
SP - 253-259
ER -
TY - JOUR
TI - Commercial fungicide formulations induce in vitro oospore formation and phenotypic change in mating type in Phytophthora infestans
AU - Groves, Carol Trout
AU - Ristaino, Jean Beagle
T2 - Phytopathology
DA - 2000///
PY - 2000///
VL - 90
IS - 11
SP - 1201-1208
ER -
TY - JOUR
TI - Ethylene signaling: From mutants to molecules
AU - Stepanova, A.N.
AU - Ecker, J.R.
T2 - Current Opinion in Plant Biology
AB - The past decade has been incredibly productive for ethylene researchers. Major components in the ethylene signaling pathway in plants have been identified and characterized. The past year's contributions include the crystallographic analysis of the Arabidopsis ETR1 receiver domain, antisense studies of the tomato ethylene receptor genes LeETR4 and NR, and the cloning and functional characterization of several Arabidopsis EREBP-related transcription activators and repressors, and of an EIN3-ortholog of tobacco. Additional evidence for the interconnection of the ethylene and auxin responses was provided by the cloning and characterization of Arabidopsis NPH4. Finally, the first discovery of ethylene responsiveness in an animal species implied a more universal role for ethylene than previously thought.
DA - 2000///
PY - 2000///
DO - 10.1016/S1369-5266(00)00096-0
VL - 3
IS - 5
SP - 353-360
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033832308&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana
AU - Theologis, Athanasios
AU - Ecker, Joseph R.
AU - Palm, Curtis J.
AU - Federspiel, Nancy A.
AU - Kaul, Samir
AU - White, Owen
AU - Alonso, Jose
AU - Altafi, Hootan
AU - Araujo, Rina
AU - Bowman, Cheryl L.
T2 - Nature
DA - 2000///
PY - 2000///
VL - 408
IS - 6814
SP - 816-820
ER -
TY - JOUR
TI - Involvement of NRAMP1 from Arabidopsis thaliana in iron transport
AU - Curie, Catherine
AU - Alonso, J.
AU - Le Jean, Marie
AU - Ecker, J.
AU - Briat, J.
T2 - Biochem. J
AB - Nramp genes code for a widely distributed class of proteins involved in a variety of processes, ranging from the control of susceptibility to bacterial infection in mammalian cells and taste behaviour in Drosophila to manganese uptake in yeast. Some of the NRAMP proteins in mammals and in yeast are capable of transporting metal ions, including iron. In plants, iron transport was shown to require a reduction/Fe(II) transport system. In Arabidopsis thaliana this process involves the IRT1 and Fro2 genes. Here we report the sequence of five NRAMP proteins from A. thaliana. Sequence comparison suggests that there are two classes of NRAMP proteins in plants: A. thaliana (At) NRAMP1 and Oriza sativa (Os) NRAMP1 and 3 (two rice isologues) represent one class, and AtNRAMP2-5 and OsNRAMP2 the other. AtNramp1 and OsNramp1 are able to complement the fet3fet4 yeast mutant defective both in low- and high-affinity iron transports, whereas AtNramp2 and OsNramp2 fail to do so. In addition, AtNramp1 transcript, but not AtNramp2 transcript, accumulates in response to iron deficiency in roots but not in leaves. Finally, overexpression of AtNramp1 in transgenic A. thaliana plants leads to an increase in plant resistance to toxic iron concentration. Taken together, these results demonstrate that AtNramp1 participates in the control of iron homoeostasis in plants.
DA - 2000///
PY - 2000///
DO - 10.1042/0264-6021:3470749
VL - 347
SP - 749-755
KW - iron deficiency
KW - iron toxicity
KW - Nramp
KW - plant
KW - transport
ER -
TY - JOUR
TI - Ethylene captures a metal! Metal ions are involved in ethylene perception and signal transduction
AU - Hirayama, Takashi
AU - Alonso, Jose M.
T2 - Plant and Cell Physiology
DA - 2000///
PY - 2000///
VL - 41
IS - 5
SP - 548-555
ER -
TY - CHAP
TI - AMBULATORY ELECTROCARDIOGRAPHY
AU - DeFrancesco, Teresa C.
T2 - Small Animal Cardiology Secrets
PY - 2000///
DO - 10.1016/b978-1-56053-352-8.50024-9
SP - 115-118
OP -
PB - Elsevier
SN - 9781560533528
UR - http://dx.doi.org/10.1016/b978-1-56053-352-8.50024-9
DB - Crossref
ER -
TY - JOUR
TI - Identification and chromosomal localization of the monkey retrotransposon in Musa sp.
AU - Balint-Kurti, P. J.
AU - Clendennen, S. K.
AU - Doleželová, M.
AU - Valárik, M.
AU - Doležel, J.
AU - Beetham, P. R.
AU - May, G. D.
T2 - Molecular and General Genetics MGG
DA - 2000/8//
PY - 2000/8//
DO - 10.1007/s004380000265
VL - 263
IS - 6
SP - 908-915
J2 - Mol Gen Genet
LA - en
OP -
SN - 0026-8925 1432-1874
UR - http://dx.doi.org/10.1007/s004380000265
DB - Crossref
ER -
TY - JOUR
TI - Fruit-specific lectins from banana and plantain
AU - Peumans, Willy J.
AU - Zhang, Wenling
AU - Barre, Annick
AU - Astoul, Corinne Houlè\mathsemicolons
AU - Balint-Kurti, Peter J.
AU - Rovira, Paula
AU - Rougé\mathsemicolon, Pierre
AU - May, Gregory D.
AU - Leuven, Fred Van
AU - Truffa-Bachi, Paolo
AU - Damme, Els J. M. Van
T2 - Planta
DA - 2000/9//
PY - 2000/9//
DO - 10.1007/s004250000307
VL - 211
IS - 4
SP - 546-554
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033786158&partnerID=MN8TOARS
KW - fruit lectins
KW - jacalin
KW - lectin
KW - mannose
KW - Musa
KW - plantain
ER -
TY - JOUR
TI - The use of RT-PCR differential display in single-celled organisms and plant tissues
AU - NUCCIO, MICHAEL L
AU - HSIEH, TZUNG-FU
AU - THOMAS, TERRY L
T2 - Differential Display: A Practical Approach
DA - 2000///
PY - 2000///
IS - 224
SP - 83
ER -
TY - JOUR
TI - Fluctuations in HIV-1 Viral Load Are Correlated to CD4+ T-Lymphocyte Count During the Natural Course of Infection
AU - Masel, Joanna
AU - Arnaout, Ramy A.
AU - O'Brien, Thomas R.
AU - Goedert, James J.
AU - Lloyd, Alun L.
T2 - JAIDS Journal of Acquired Immune Deficiency Syndromes
AB - Background: To find out about the prophylactic value of antiretroviral therapy on HIV-1-associated subclinical and clinical psychomotor slowing as one marker of HIV-1-associated CNS disease. Methods: Prospective study with regular clinical and neurophysiologic examination every three months of 1482 consecutive HIV-1-seropositive and AIDS patients seen at our department till June 30, 1999. Results: Antiretroviral therapy has a significant prophylactic value over an individual observation period of ten years with regard to the first, potentially transient manifestation of HIV-1-associated subclinical psychomotor slowing and with regard to the clinical manifestation of motor signs. However, a subgroup of patients is characterized through a second, more sustained manifestation of subclinical psychomotor slowing which cannot be prevented by any type of currently available antiretroviral therapy. Conclusions: These findings suggest the existence of different pathomechanisms underlying HIV-1-associated brain disease which may in part be effectively prevented, but which in part also escape all antiretroviral treatment strategies in use today.
DA - 2000/4//
PY - 2000/4//
DO - 10.1097/00126334-200004150-00003
VL - 23
IS - 5
SP - 375-379
J2 - JAIDS Journal of Acquired Immune Deficiency Syndromes
LA - en
OP -
SN - 1525-4135
UR - http://dx.doi.org/10.1097/00126334-200004150-00003
DB - Crossref
ER -
TY - JOUR
TI - Local stability analysis of spatially homogeneous solutions of multi-patch systems
AU - Jansen, Vincent A.A.
AU - Lloyd, Alun L.
T2 - Journal of Mathematical Biology
DA - 2000/9/1/
PY - 2000/9/1/
DO - 10.1007/s002850000048
VL - 41
IS - 3
SP - 232-252
J2 - Journal of Mathematical Biology
OP -
SN - 0303-6812 1432-1416
UR - http://dx.doi.org/10.1007/s002850000048
DB - Crossref
KW - diffusive instability
KW - symmetry breaking
KW - metapopulation model
KW - coupled map lattice
ER -
TY - JOUR
TI - The Influence of HLA Class I Alleles and Heterozygosity on the Outcome of Human T Cell Lymphotropic Virus Type I Infection
AU - Jeffery, Katie J. M.
AU - Siddiqui, Asna A.
AU - Bunce, Mike
AU - Lloyd, Alun L.
AU - Vine, Alison M.
AU - Witkover, Aviva D.
AU - Izumo, Shuji
AU - Usuku, Koichiro
AU - Welsh, Kenneth I.
AU - Osame, Mitsuhiro
AU - Bangham, Charles R. M.
T2 - The Journal of Immunology
AB - The inflammatory disease human T cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM/TSP) occurs in only 1-2% of HTLV-I-infected individuals and is associated with a high provirus load of HTLV-I. We hypothesize that a person's risk of developing HAM/TSP depends upon the efficiency of their immune response to the virus, which differs between individuals because of polymorphism in genes that influence this response. Previously we showed that the possession of HLA-A*02 was associated with a lower risk of HAM/TSP, and with a lower provirus load in healthy carriers of HTLV-I. However, HLA-A*02 did not account for all the observed difference in the risk of HAM/TSP. Here we present evidence, in the same study population in Japan, that HLA-Cw*08 was also associated with disease protection (probability value, two-tailed test = 0.002) and with a lower proviral load in healthy carriers. Possession of the A*02 and/or Cw*08 genes prevented 36% of potential HAM/TSP cases. In contrast, HLA-B*5401 was associated with a higher susceptibility to HAM/TSP (probability value, two-tailed test = 0.0003) and with a higher provirus load in HAM/TSP patients. At a given provirus load, B*5401 appeared to increase the risk of disease. The fraction of HAM/TSP cases attributable to B*5401 was 17%. Furthermore, individuals who were heterozygous at all three HLA class I loci have a lower HTLV-I provirus load than those who were homozygous at one or more loci. These results are consistent with the proposal that a strong class I-restricted CTL response to HTLV-I reduces the proviral load and hence the risk of disease.
DA - 2000/12/15/
PY - 2000/12/15/
DO - 10.4049/jimmunol.165.12.7278
VL - 165
IS - 12
SP - 7278-7284
J2 - J Immunol
LA - en
OP -
SN - 0022-1767 1550-6606
UR - http://dx.doi.org/10.4049/jimmunol.165.12.7278
DB - Crossref
ER -
TY - JOUR
TI - What Are Burpless Cucumbers?
AU - Wehner, Todd C.
T2 - HortTechnology
AB - Burpless cucumbers are listed in many seed catalogs as being milder in taste (or easier on the digestion) than the american slicing type. It has been suggested by researchers that burpless cucumbers 1) contain less of a burp-causing compound, 2) are genetically bitterfree, or 3) are just the marketing term for oriental trellis cucumbers sold in the U.S. The objective of this experiment was to determine whether oriental trellis cucumbers cause less burping when eaten, and whether they are genetically bitterfree. An american slicer (`Marketmore 76'), a bitterfree slicer (`Marketmore 80'), and a burpless oriental trellis slicer (`Tasty Bright') were compared. Burpiness of the fruit was determined in the field in two seasons (spring and summer) and two replications. Six judges were grouped into burp-susceptible and burp-resistant. They evaluated the cultivars over two harvests by eating a 4-inch (100-mm) length of one fruit of the three cultivars (in random order) on three consecutive days. Burpiness was rated 0 to 9 (0 = none, 1 to 3 = slight, 4 to 6 = moderate, 7 to 9 = severe). Bitterness of the plants was determined (using different judges) by tasting one cotyledon of six seedlings per cultivar. Cotyledon bitterness is an indicator of plant bitterness; bitterfree plants lack cucurbitacins, and have mild-tasting fruit. Results of taste tests indicated that burpiness ratings were not significantly differentfor burp resistant judges. However, oriental trellis cucumbers were slightly but significantly milder than american slicers for judges susceptible to burping. `Marketmore 76' and `Tasty Bright' were normal-bitter, and `Marketmore 80' was bitterfree. An additional 11 oriental trellis cultivars were also tested for bitterness to determine whether Tasty Bright was typical in bitterness; they were all normal-bitter. In conclusion, oriental trellis cucumbers are not bitterfree, but are slightly milder for burp-susceptible people to eat. Finally, burpless is the marketing term for oriental trellis cucumbers in the United States.
DA - 2000/1//
PY - 2000/1//
DO - 10.21273/horttech.10.2.317
VL - 1
SP - 317-320
OP -
SN - 1063-0198 1943-7714
UR - http://dx.doi.org/10.21273/horttech.10.2.317
DB - Crossref
ER -
TY - JOUR
TI - Evolutionary relationships between the amphibian, avian, and mammalian stomachs
AU - Smith, Devyn M.
AU - Grasty, Rayetta C.
AU - Theodosiou, Nicole A.
AU - Tabin, Clifford J.
AU - Nascone-Yoder, Nanette M.
T2 - Evolution and Development
AB - SUMMARY Although the gut is homologous among different vertebrates, morphological differences exist between different species. The most obvious variation in the guts of extant vertebrates appears in the stomach. To investigate the evolution of this structure, we compared the histology of the stomach and gastrointestinal tract in amphibian ( Xenopus laevis ), avian ( Gallus gallus ), and mammalian ( Mus musculus ) organisms, and defined the expression patterns of several genes within the developing guts of these lineages. In all three groups, we find that the anterior portion of the stomach has a similar glandular histology as well as a common embryonic expression of the secreted factors Wnt5a and BMP‐4. Likewise, within the amniote lineages, the posterior nonglandular stomach and pyloric sphincter regions are also comparable in both histological and molecular phenotypes. The posterior stomach expresses Six2 , BMPR1B , and Barx1 , whereas the pyloric sphincter expresses Nkx2.5. Although the adult Xenopus stomach exhibits both glandular and aglandular regions and a distinct pyloric sphincter similar to that of the amniotic vertebrates, the histology of the Xenopus tadpole gut shows less distinct variation in differentiation in this region, which is most likely a derived condition. The molecular signature of the embryonic Xenopus gut correlates with the more derived morphology of the larval phase. We conclude that the global patterning of the gut is remarkably similar among the different vertebrate lineages. The distinct compartments of gene expression that we find in the gut be necessary for the unique morphological specializations that distinguish the stomachs from terrestrial vertebrates.
DA - 2000/11//
PY - 2000/11//
DO - 10.1046/j.1525-142x.2000.00076.x
VL - 2
IS - 6
SP - 348-359
J2 - Evol Dev
LA - en
OP -
SN - 1520-541X 1525-142X
UR - http://dx.doi.org/10.1046/j.1525-142x.2000.00076.x
DB - Crossref
ER -
TY - CHAP
TI - Post-Transcriptional Light Regulation of Nuclear-Encoded Genes
AU - Petracek, Marie E.
AU - Thompson, W. F.
T2 - Genetic Engineering
PY - 2000///
DO - 10.1007/978-1-4615-4199-8_1
SP - 1-10
OP -
PB - Springer US
SN - 9781461368847 9781461541998
UR - http://dx.doi.org/10.1007/978-1-4615-4199-8_1
DB - Crossref
ER -
TY - CONF
TI - Polyploidy: From evolution to landscape plant improvement
AU - Ranney, T.G.
C2 - 2000///
C3 - Proceedings of the 11th Conference of the Metropolitan Tree Improvement Alliance
DA - 2000///
ER -
TY - CONF
TI - Evaluating fire blight resistance among flowering crabapples (Malus spp.)
AU - Bell, A.C.
AU - Ranney, T.G.
AU - Eaker, T.A.
AU - Sutton, T.B.
C2 - 2000///
C3 - Proceedings of the Southern Nursery Association Research Conference, 45th Annual Report
DA - 2000///
SP - 244–248
ER -
TY - CONF
TI - Effects of heat and drought on photosynthesis in redbuds
AU - Griffin, J.J.
AU - Ranney, T.G.
C2 - 2000///
C3 - Proceedings of the Southern Nursery Association Research Conference, 45th Annual Report
DA - 2000///
SP - 464–467
ER -
TY - CONF
TI - Controlled screening of flowering pears and crabapples for resistance to fire blight
AU - Bell, A.C.
AU - Ranney, T.G.
AU - Eaker, T.A.
AU - Sutton, T.B.
C2 - 2000///
C3 - Proceedings of the 11th Conference of the Metropolitan Tree Improvement Alliance
DA - 2000///
ER -
TY - JOUR
TI - Length variation of the nuclear ribosomal DNA internal transcribed spacer in the genus Abies, with references to its systematic utility in Pinaceae
AU - Xiang, Q.P.
AU - Xiang, Q.Y.
AU - Liston, A.
AU - Fu, L.K.
AU - Fu, D.Z.
T2 - Acta Botanica Sinica
DA - 2000///
PY - 2000///
VL - 42
SP - 946–951
ER -
TY - JOUR
TI - Regulation of gynoecium marginal tissue formation by LEUNIG and AINTEGUMENTA
AU - Liu, Z.
AU - Franks, R.G.
AU - Klink, V.P.
T2 - Plant Cell
AB - The carpel is the female reproductive organ of flowering plants. In Arabidopsis, congenital fusion of two carpels leads to the formation of an enclosed gynoecium. The margins of the two fused carpels are meristematic in nature and give rise to placentas, ovules, septa, abaxial repla, and the majority of the stylar and stigmatic tissues. Thus, understanding how the marginal tissues are specified and identifying genes that direct their development may provide important insight into higher plant reproductive development. In this study, we show that LEUNIG and AINTEGUMENTA are two critical regulators of marginal tissue development. Double mutants of leunig aintegumenta fail to develop placentas, ovules, septa, stigma, and style. This effect is specific to the leunig aintegumenta double mutant and is not found in other double mutant combinations such as leunig apetala2 or aintegumenta apetala2. Additional analyses indicate that the absence of marginal tissues in leunig aintegumenta double mutants is not mediated by ectopic AGAMOUS. We propose that LEUNIG and AINTEGUMENTA act together to control the expression of common target genes that regulate cell proliferation associated with marginal tissue development.
DA - 2000///
PY - 2000///
DO - 10.1105/tpc.12.10.1879
VL - 12
IS - 10
SP - 1879-1891
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033768403&partnerID=MN8TOARS
ER -
TY - JOUR
TI - THE RELATIONSHIP OF FILAMENT LEVELS TO FOAMING IN ACTIVATED SLUDGE DETERMINED BY OLIGONUCLEOTIDE PROBE HYBRIDIZATIONS
AU - Reyes, Francis L.
AU - Raskin, Lutgarde
T2 - proc water environ fed
AB - THE RELATIONSHIP OF FILAMENT LEVELS TO FOAMING IN ACTIVATED SLUDGE DETERMINED BY OLIGONUCLEOTIDE PROBE HYBRIDIZATIONSThe relationship between the levels of mycolic acid-containing actinomycetes (mycolata), Gordonia spp., and Gordonia amarae, and foam initiation and stability was characterized using (1) batch tests involving addition of G. amarae cells to activated sludge, and (2) analysis of a full-scale activated sludge plant that experienced seasonal foaming. Filament levels were quantified using group-,...Author(s)Francis L. de los ReyesLutgarde RaskinSourceProceedings of the Water Environment FederationSubjectSession 1 - Research Symposium: Sustainability and Excellence in Water ResearchDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2000ISSN1938-6478SICI1938-6478(20000101)2000:14L.13;1-DOI10.2175/193864700784607460Volume / Issue2000 / 14Content sourceWEFTECFirst / last page(s)13 - 21Copyright2000Word count146
DA - 2000/1/1/
PY - 2000/1/1/
DO - 10.2175/193864700784607460
VL - 2000
IS - 14
SP - 13-21
ER -
TY - JOUR
TI - Molecular characterization of an avian astrovirus
AU - Koci, M.D.
AU - Seal, B.S.
AU - Schultz-Cherry, S.
T2 - Journal of Virology
AB - Astroviruses are known to cause enteric disease in several animal species, including turkeys. However, only human astroviruses have been well characterized at the nucleotide level. Herein we report the nucleotide sequence, genomic organization, and predicted amino acid sequence of a turkey astrovirus isolated from poults with an emerging enteric disease.
DA - 2000///
PY - 2000///
DO - 10.1128/JVI.74.13.6173-6177.2000
VL - 74
IS - 13
SP - 6173-6177
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034123772&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Identifying Agent(s) Associated with Poult Enteritis Mortality Syndrome: Importance of the Thymus
AU - Schultz-Cherry, Stacey
AU - Kapczynski, Darrell R.
AU - Simmons, Valrie M.
AU - Koci, Matthew D.
AU - Brown, Corrie
AU - Barnes, H. John
T2 - Avian Diseases
AB - Poult enteritis mortality syndrome (PEMS), a highly infectious disease of young turkeys, causes serious financial losses to the turkey industry. Clinically, PEMS is defined by mortality profiles, diarrhea, growth depression, and immunosuppression. Although many viruses, bacteria, and parasites are found in PEMS-infected birds, the inciting agent remains unknown. Experimentally, PEMS can be reproduced by exposing naïve poults to the intestinal contents from infected birds. Previous reports suggest that extraintestinal tissues fail to reproduce the disease. Histopathologic examination of tissues from PEMS-infected poults suggested that the thymus exhibited the earliest signs of pathology. On the basis of these observations, we hypothesized that the thymus harbors an agent(s) involved in PEMS. In these studies, naïve turkey poults were orally inoculated with a bacteria-free filtrate composed of either the intestines and feces or the thymus from PEMS-infected birds and were monitored for clinical signs of PEMS. Poults exposed to a filtrate composed solely of the thymus from PEMS-infected birds exhibited diarrhea, growth depression, mortality, pathology, and, most importantly, immunosuppression similar to poults exposed to the intestinal filtrate. The results of this study suggest that the thymus of infected birds harbors the agent(s) that can reproduce a PEMS-like disease in turkey poults.
DA - 2000/4//
PY - 2000/4//
DO - 10.2307/1592538
VL - 44
IS - 2
SP - 256
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034088250&partnerID=MN8TOARS
KW - immunity
KW - immunosuppression
KW - lymphocytes
KW - poult enteritis mortality syndrome
KW - PEMS
KW - T cells
KW - thymus
KW - turkeys
ER -
TY - JOUR
TI - Development of an RT-PCR diagnostic test for an avian astrovirus
AU - Koci, Matthew D
AU - Seal, Bruce S
AU - Schultz-Cherry, Stacey
T2 - Journal of Virological Methods
AB - Astroviruses are small round viruses that cause enteric disease in the young of several species. Detection and diagnosis of astrovirus infection in non-human hosts relies heavily on electron microscopy and fluorescent antibody tests. Recently, our laboratory isolated and sequenced an avian astrovirus from poult enteritis mortality syndrome affected turkeys. These studies describe the development of RT-PCR methods, which specifically detect regions of the viral capsid and polymerase genes, and demonstrate their use in detecting astrovirus infection in commercial turkey flocks.
DA - 2000/10//
PY - 2000/10//
DO - 10.1016/s0166-0934(00)00228-7
VL - 90
IS - 1
SP - 79-83
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033813102&partnerID=MN8TOARS
KW - turkey astrovirus
KW - RT-PCR
KW - poult enteritis mortality syndrome
ER -
TY - JOUR
TI - The zebrafish fth1, slc3a2, men1, pc, fgf3 and cycd1 genes define two regions of conserved synteny between linkage group 7 and human chromosome 11q13
AU - Yoder, JA
AU - Litman, GW
T2 - GENE
AB - In addition to being an excellent model system for studying vertebrate development, the zebrafish has become a great tool for gene discovery by mutational analysis. The recent availability of the zebrafish EST database and radiation hybrid mapping panels has dramatically expanded the framework for genomic research in this species. Developing comparative maps of the zebrafish and human genomes is of particular importance for zebrafish mutagenesis studies in which human orthologs are sought for zebrafish genes. However, only partial cDNA sequences are determined routinely for mapped ESTs, leaving the identity of the EST in question. It previously had been reported that zebrafish linkage group 7 shares conserved synteny with human chromosome 11q13. In an effort to further define this relationship, five full-length zebrafish cDNAs, fth1, slc3a2, prkri, cd81, and pc, as well as one putative human gene, DBX were identified and their map positions ascertained. These six genes, along with men1, fgf3 and cycd1 define two regions of conserved synteny between linkage group 7 and 11q13.
DA - 2000/12/31/
PY - 2000/12/31/
DO - 10.1016/S0378-1119(00)00503-5
VL - 261
IS - 2
SP - 235-242
SN - 0378-1119
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034739814&partnerID=MN8TOARS
KW - T51 radiation hybrid panel
KW - LN54 radiation hybrid panel
KW - hlx1
KW - DBX
KW - prkri
KW - cd81
ER -
TY - CHAP
TI - Immune-Type Diversity in the Absence of Somatic Rearrangement
AU - Yoder, Jeffrey
AU - Litman, G. W.
T2 - Current Topics in Microbiology and Immunology
AB - The rearrangement and joining of segmental elements during the differentiation of B and T lymphocytes in apparently all jawed vertebrate species results in the primary diversification of the immune receptor genes encoding both immunoglobulin (Ig) and T cell antigen receptor (TCR) genes. Although an extraordinary degree of interspecific variation in both numbers of recombining elements and mechanisms of secondary diversification of rearranged Ig genes has been described throughout vertebrate phylogeny, the basic mechanisms involved in the somatic rearrangement of individual gene segments have been intensely conserved. Recent studies of the recombination process (reviewed in Grawunder et al. 1998) and the enzymatic machinery that catalyzes DNA-mediated genetic rearrangement events have resulted in an increasingly clearer understanding of not only this highly complex process but also of the probable origin of the rearrangement mechanism itself (Agrawal et al. 1998; Hiom et al. 1998).
PY - 2000///
DO - 10.1007/978-3-642-59674-2_12
VL - 248
SP - 271–282
UR - http://dx.doi.org/10.1007/978-3-642-59674-2_12
ER -
TY - JOUR
TI - Shoot growth patterns related to growth and adaptation of Pinus brutia
AU - Isik, F.
AU - Isik, K.
AU - Yildirim, T.
AU - Li, B.
T2 - Bildiri, IUFRO XXI World Forestry Congress
DA - 2000///
PY - 2000///
VL - 11
ER -
TY - JOUR
TI - Interstock effects on strobilus initiation in topgrafted loblolly pine
AU - McKeand, S. E.
AU - Raley, E. M.
T2 - Forest Genetics
DA - 2000///
PY - 2000///
VL - 7
SP - 179-182
ER -
TY - JOUR
TI - Grafting loblolly pine
AU - McKeand, S. E.
AU - Jett, J. B.
T2 - Bulletin of the American Conifer Society
DA - 2000///
PY - 2000///
VL - 17
IS - 1
SP - 22-30
ER -
TY - JOUR
TI - Tree genomes: What will we understand about them by the year 2020 and how might we use that knowledge?
AU - Sederoff, R. R.
T2 - Forest genetics and sustainability
AB - The purpose of this paper is to speculate about the future applications of molecular genetics to the understanding and utilization of tree genomes. Biotechnology of forest trees is a young discipline. The first genetically engineered tree, a glyphosate tolerant hybrid poplar, was produced in 1987 (Fillatti et al., 1987). Since that time, biotechnology of forest trees has incorporated new technology of genetic mapping and has now entered the era of genomics. Much of what follows here is only one person’s speculations about scientific progress into a relatively near future. In general, scientists are less effective at predicting the future of science than are writers of fiction, who are less constrained about predictions. The time frame of this paper is to look forward to the year 2020, which is approximately one rotation age for a temperate pine, and as much as four rotations for a tropical hardwood. The purpose of this short review is not to be comprehensive, nor to provide access to key references, but to provide an overview of ideas related to application to forest trees of existing technology in the relatively near future.
DA - 2000///
PY - 2000///
DO - 10.1007/978-94-017-1576-8_4
SP - 23
ER -
TY - JOUR
TI - Root architectural plasticity to nutrient stress in two contrasting ecotypes of loblolly pine
AU - Wu, R. L.
AU - Grissom, J. E.
AU - O'Malley, D. M.
AU - McKeand, Steven
T2 - Journal of Sustainable Forestry
DA - 2000///
PY - 2000///
DO - 10.1300/j091v10n03_13
VL - 10
IS - 3
SP - 307
ER -
TY - JOUR
TI - Detection of resistant insects and IPM
AU - Roe, R. M.
AU - Bailey, W. D.
AU - Gould, F.
AU - Sorenson, C. E.
AU - Kennedy, G. G.
AU - Bacheler, J. S.
AU - Rose, R. L.
AU - Hodgson, E.
AU - Sutula, C. L.
T2 - Emerging technologies for integrated pest management : concepts, research, and implementation
DA - 2000///
PY - 2000///
SP - 67
ER -
TY - JOUR
TI - Breeding for high fruit yield in cucumber
AU - Shetty, NV
AU - Wehner, TC
T2 - PROCEEDINGS OF CUCURBITACEAE 2000
DA - 2000///
PY - 2000///
DO - 10.17660/actahortic.2000.510.3
IS - 510
SP - 21-27
SN - 0567-7572
KW - Cucumis sativus
KW - vegetable breeding
ER -
TY - CHAP
TI - The evolutionary history of the Mesoamerican Oocarpae
AU - Dvorak, W. S.
AU - Jordan, A. P.
AU - Hodge, G. R.
AU - Romero, J. L.
AU - Woodbridge, W. C.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 1
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - JOUR
TI - Sustainable use of genetically modified crops in developing countries
AU - Gould, F.
AU - Cohen, M. B.
T2 - Agricultural biotechnology and the poor: proceedings of an international conference, Washington, DC, USA, 21-22 October, 1999
DA - 2000///
PY - 2000///
SP - 139
ER -
TY - JOUR
TI - Reassessing autocidal pest control
AU - Gould, F.
AU - Schliekelman, P.
T2 - Emerging technologies for integrated pest management : concepts, research, and implementation
DA - 2000///
PY - 2000///
SP - 190
ER -
TY - CHAP
TI - Pinus tecunumanii
AU - Dvorak, W. S.
AU - Hodge, G. R.
AU - Gutierrez, E. A.
AU - Osorio, L. F.
AU - Malan, F. S.
AU - Stanger, T. K.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 188
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus patula
AU - Dvorak, W. S.
AU - Hodge, G. R.
AU - Kietzka, J. E.
AU - Malan, F.
AU - Osorio, L. F.
AU - Stanger, T. K.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 148
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus oocarpa
AU - Dvorak, W. S.
AU - Gutierrez, E. A.
AU - Osorio, L. F.
AU - Hodge, G. R.
AU - Brawner, J. T.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 128
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus maximinoi
AU - Dvorak, W. S.
AU - Gutierrez, E. A.
AU - Gapare, W. J.
AU - Hodge, G. R.
AU - Osorio, L. F.
AU - Bester, C.
AU - Kikuti, P.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 106
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus jaliscana
AU - Dvorak, W. S.
AU - Jordan, A. P.
AU - Rosa, J.
AU - Hodge, G. R.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 86
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus greggii
AU - Dvorak, W. S.
AU - Kietzka, J. E.
AU - Donahue, J. K.
AU - Hodge, G. R.
AU - Stanger, T. K.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 52
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - Pinus caribaea var. hondurensis
AU - Dvorak, W. S.
AU - Gutierrez, E. A.
AU - Hodge, G. R.
AU - Romero, J. L.
AU - Stock, J.
AU - Rivas, O.
T2 - Conservation and testing of tropical and subtropical forest tree species by the CAMCORE Cooperative
PY - 2000///
SP - 12
PB - Botha Hill, South Africa : Grow Graphics
SN - 0620264608
ER -
TY - CHAP
TI - CVT update: Infectious endocarditis
AU - DeFrancesco, T. C.
T2 - Kirk's current veterinary therapy : small animal practice (13th Ed.)
PY - 2000///
SP - 768
PB - Philadelphia, PA : W.B. Saunders
SN - 0721655238
ER -
TY - CHAP
TI - Optimizing secondary wall synthesis in cotton fibers
AU - Haigler, C. H.
AU - Cai, W. X.
AU - Gannaway, J. G.
AU - Grimson, M. J.
AU - Hequet, E. F.
AU - Holaday, A. S.
AU - Huang, J.-Y.
AU - Jaradat, T. T.
AU - Jividen, G. J.
AU - Krieg, D. R.
AU - Martin, L. K.
AU - Nagarur, S.
AU - Salnikov, V. V.
AU - Strauss, R. E.
AU - Tummala, J.
AU - Wan, C.-H.
AU - Wu, C.
AU - Wyatt, B. G.
AU - Zhang, H.
T2 - Genetic control of cotton fiber and seed quality
PY - 2000///
SP - 147-165
PB - Cary, NC: Cotton Incorporated
ER -
TY - JOUR
TI - Responsiveness of diverse provenances of loblolly pine to fertilization - age 4 results
AU - McKeand, Steven
AU - Grissom, J. E.
AU - Handest, J. A.
AU - O'Malley, D. M.
AU - Allen, H. L.
T2 - Journal of Sustainable Forestry
DA - 2000///
PY - 2000///
DO - 10.1300/j091v10n01_10
VL - 10
SP - 87–94
ER -
TY - JOUR
TI - Timing the eastern Asian-Eastern North American floristic disjunction: Molecular clock corroborates paleontological estimates
AU - Xiang, QY
AU - Soltis, DE
AU - Soltis, PS
AU - Manchester, , SR
AU - Crawford, DJ
T2 - MOLECULAR PHYLOGENETICS AND EVOLUTION
AB - Sequence data of the chloroplast gene rbcL were used to estimate the time of the well-known eastern Asian-eastern North American floristic disjunction. Sequence divergence of rbcL was examined for 22 species of 11 genera (Campsis, Caulophyllum, Cornus, Decumaria, Liriodendron, Menispermum, Mitchella, Pachysandra, Penthorum, Podophyllum, and Phryma) representing a diverse array of flowering plants occurring disjunctly in eastern Asia and eastern North America. Divergence times of putative disjunct species pairs were estimated from synonymous substitutions, using rbcL molecular clocks calibrated for Cornus. Relative rate tests were performed to assess rate constancy of rbcL evolution among lineages. Corrections of estimates of divergence times for each species pair were made based on rate differences of rbcL between Cornus and other species pairs. Results of these analyses indicate that the time of divergence of species pairs examined ranges from 12.56 +/- 4.30 million years to recent (<0.31 million years), with most within the last 10 million years (in the late Miocene and Pliocene). These results suggest that the isolation of most morphologically similar disjunct species in eastern Asia and eastern North America occurred during the global climatic cooling period that took place throughout the late Tertiary and Quaternary. This estimate is closely correlated with paleontological evidence and in agreement with the hypothesis that considers the eastern Asian-eastern North American floristic disjunction to be the result of the range restriction of a once more or less continuously distributed mixed mesophytic forest of the Northern Hemisphere that occurred during the late Tertiary and Quaternary. This implies that in most taxa the disjunction may have resulted from vicariance events. However, long-distance dispersal may explain the disjunct distribution of taxa with low divergence, such as Menispermum.
DA - 2000/6//
PY - 2000/6//
DO - 10.1006/mpev.2000.0766
VL - 15
IS - 3
SP - 462-472
SN - 1095-9513
ER -
TY - CONF
TI - The relationship of filament levels to foaming in activated sludge determined by Oligonucleotide Probe Hybridzations, Research Symposium (Sustainbility and excellence in environmental research), Proc.
AU - Reyes, F. L.
AU - Raskin, L.
C2 - 2000///
C3 - 73rd Water Environment Federation Annual Conference and Exposition (WEFTEC 2000), October 14-18, Anaheim, CA
CN - TD365 .W378 2001
DA - 2000///
ER -
TY - JOUR
TI - Pines as model gymnosperms to study evolution, wood formation, and perennial growth
AU - Lev-Yadun, S
AU - Sederoff, R
T2 - JOURNAL OF PLANT GROWTH REGULATION
DA - 2000/9//
PY - 2000/9//
DO - 10.1007/s003440000045
VL - 19
IS - 3
SP - 290-305
SN - 1435-8107
KW - forest biotechnology
KW - genomics
KW - gymnosperms
KW - Pinus
KW - plant longevity
KW - plant reproduction
KW - wood formation
KW - wood structure
KW - xylogenesis
ER -
TY - JOUR
TI - Nematode gene sequences, December 2000 update
AU - McCarter, J.P.
AU - Bird, D.McK.
AU - Clifton, S.W.
AU - Waterston, R.H.
T2 - Journal of Nematology
DA - 2000///
PY - 2000///
VL - 32
IS - 4
SP - 331-333
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034353966&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Rapid gene discovery in plant parasitic nematodes via Expressed Sequence Tags
AU - McCarter, J
AU - Abad, P
AU - Jones, JT
AU - Bird, D
T2 - NEMATOLOGY
AB - Abstract Projects currently underway are generating thousands of publicly available DNA sequences representing numerous genes from plant parasitic nematodes. Use of these data has the potential to revolutionise gene discovery, as well as aiding in genome physical mapping and expression profiling experiments. This article introduces sequences called expressed sequence tags or ESTs, which are single-sequence reads from randomly-selected cDNA clones. We review the process used to create these sequences and outline the strengths and weaknesses of ESTs as research tools. Instructions on how to access and use EST data also are provided. Découverte rapide de gènes chez les nématodes parasites des plantes: le point sur l'utilisation des Etiquettes de Séquences Exprimées - Les projets actuellement en cours génèrent des milliers de séquences d'ADN, publiquement disponibles, représentant de nombreux gènes de nématodes parasites des plantes. L'utilisation de ces données pourrait révolutionner la découverte des gènes en facilitant aussi bien les expériences de cartographie physique que celles de profils d'expression. Cet article présente les séquences dérivées de clones d'ADNc sélectionnés au hasard, appelées étiquettes de séquences exprimées (ESTs). Nous exposons le processus utilisé pour les générer de même que les avantages et les inconvénients des ESTs comme outils de recherche. Les instructions concernant l'accès et l'utilisation des ESTs sont également fournies.
DA - 2000///
PY - 2000///
DO - 10.1163/156854100509574
VL - 2
IS - 7
SP - 719-731
SN - 1388-5545
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034467290&partnerID=MN8TOARS
KW - Caenorhabditis elegans
KW - clustering
KW - EST
KW - Globodera
KW - Meloidogyne
KW - NemaGene
ER -
TY - CONF
TI - Can information engineering enhance information quality for effective decision-making in textiles?
AU - Karpe, Y.
AU - Hodge, G.
AU - Cahill, N.
AU - Oxenham, W.
A2 - Klein, B. D.
A2 - Rossin, D. F.
C2 - 2000///
C3 - Proceedings of the 2000 Conference on Information Quality
CN - QA76.9 .D3 I524 2000
DA - 2000///
PB - Cambridge, MA: Massachusetts Institute of Technology
ER -
TY - JOUR
TI - Unusual presentation of nutritional secondary hyperparathyroidism in a Paint colt
AU - Little, D.
AU - Redding, W.R.
AU - Spaulding, K.A.
AU - Dupree, S.H.
AU - Jones, S.L.
T2 - Equine Veterinary Education
AB - Equine Veterinary EducationVolume 12, Issue 6 p. 297-302 Unusual presentation of nutritional secondary hyperparathyroidism in a Paint colt D. Little, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorW. R. Redding, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorK. A. Spaulding, Anatomy, Physiology and Radiology, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorS. H. Dupree, Veterinary Teaching Hospital, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorS. L. Jones, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this author D. Little, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorW. R. Redding, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorK. A. Spaulding, Anatomy, Physiology and Radiology, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorS. H. Dupree, Veterinary Teaching Hospital, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this authorS. L. Jones, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA.Search for more papers by this author First published: 05 January 2010 https://doi.org/10.1111/j.2042-3292.2000.tb00064.xCitations: 3AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Citing Literature Volume12, Issue6December 2000Pages 297-302 RelatedInformation
DA - 2000///
PY - 2000///
DO - 10.1111/j.2042-3292.2000.tb00064.x
VL - 2
IS - 6
SP - 388–394
ER -
TY - JOUR
TI - Plant parasitic nematodes: Habitats, hormones, and horizontally-acquired genes
AU - Bird, D.M.
AU - Koltai, H.
T2 - Journal of Plant Growth Regulation
DA - 2000///
PY - 2000///
VL - 19
IS - 2
SP - 183-194
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033758702&partnerID=MN8TOARS
ER -
TY - JOUR
TI - A sheep in wolf's clothing: Listeria innocua strains with teichoic acid-associated surface antigens and genes characteristic of Listeria monocytogenes serogroup 4
AU - Lan, Z
AU - Fiedler, F
AU - Kathariou, S
T2 - JOURNAL OF BACTERIOLOGY
AB - ABSTRACT Listeria monocytogenes serotype 4b has been implicated in numerous food-borne epidemics and in a substantial fraction of sporadic listeriosis. A unique lineage of the nonpathogenic species Listeria innocua was found to express teichoic acid-associated surface antigens that were otherwise expressed only by L. monocytogenes of serotype 4b and the rare serotypes 4d and 4e. These L. innocua strains were also found to harbor sequences homologous to the gene gtcA , which has been shown to be essential for teichoic acid glycosylation in L. monocytogenes serotype 4b. Transposon mutagenesis and genetic studies revealed that the gtcA gene identified in this lineage of L. innocua was functional in serotype 4b-like glycosylation of the teichoic acids of these organisms. The genomic organization of the gtcA region was conserved between this lineage of L. innocua and L. monocytogenes serotype 4b. Our data are in agreement with the hypothesis that, in this lineage of L. innocua , gtcA was acquired by lateral transfer from L. monocytogenes serogroup 4. The high degree of nucleotide sequence conservation in the gtcA sequences suggests that such transfer was relatively recent. Transfer events of this type may alter the surface antigenic properties of L. innocua and may eventually lead to evolution of novel pathogenic lineages through additional acquisition of genes from virulent listeriae.
DA - 2000/11//
PY - 2000/11//
DO - 10.1128/JB.182.21.6161-6168.2000
VL - 182
IS - 21
SP - 6161-6168
SN - 0021-9193
ER -
TY - JOUR
TI - Simulation of coupled turbulent flow and heat transfer in the wedge-shaped pool of a twin-roll strip casting process
AU - Kim, WS
AU - Kim, DS
AU - Kuznetsov, AV
T2 - INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
AB - The proper choice of nozzle in a twin-roll strip casting process is important to obtain the stabilization of the molten steel and free surface and a stable temperature distribution in a wedge-shaped pool. In this study, a numerical investigation of the coupled turbulent flow and heat transfer in a twin-roll strip casting process was performed for two patterns of melt-feed through a nozzle. In addition, the patterns for the removal of superheat for different gap thicknesses were analyzed using a local Nusselt number along the roll surface. The flow turbulence was examined using the low-Reynolds-number k–ε turbulence model of Launder and Sharma. The results show that the use of a submerged nozzle may have a beneficial impact on the stabilization of the free-surface zone. The increased gap thickness yields an increased local Nusselt number in the downstream section of the wedge-shaped pool where the cross-sectional flow area is reduced.
DA - 2000/10//
PY - 2000/10//
DO - 10.1016/S0017-9310(00)00013-2
VL - 43
IS - 20
SP - 3811-3822
SN - 0017-9310
ER -
TY - JOUR
TI - Screening the cucumber germplasm collection for resistance to gummy stem blight in North Carolina field tests
AU - Wehner, T. C.
AU - Shetty, N. V.
T2 - HortScience
DA - 2000///
PY - 2000///
VL - 35
IS - 6
SP - 1132-1140
ER -
TY - JOUR
TI - Regulation by homeoproteins: A comparison of deformed- responsive elements
AU - Pederson, J. A.
AU - LaFollette, J. W.
AU - Gross, C.
AU - Veraksa, A.
AU - McGinnis, W.
AU - Mahaffey, J. W.
T2 - Genetics
DA - 2000///
PY - 2000///
VL - 156
IS - 2
SP - 677-686
ER -
TY - PAT
TI - Methods for within family selection in woody perennials using genetic markers
AU - O'Malley, D. M.
AU - Sederoff, R. R.
AU - Grattapaglia, D.
C2 - 2000///
DA - 2000///
PY - 2000///
ER -
TY - JOUR
TI - Larval dispersal and survival of Scirpophaga incertulas (Lepidoptera : Pyralidae) and Chilo suppressalis (Lepidoptera : Crambidae) on cry1Ab-transformed and non-transgenic rice
AU - Dirie, AM
AU - Cohen, MB
AU - Gould, F
T2 - ENVIRONMENTAL ENTOMOLOGY
AB - Journal Article Larval Dispersal and Survival of Scirpophaga incertulas (Lepidoptera: Pyralidae) and Chilo suppressalis (Lepidoptera: Crambidae) on cry1Ab-transformed and Non-transgenic Rice Get access Ahmed M. Dirie, Ahmed M. Dirie 1Entomology and Plant Pathology Division, International Rice Research Institute, MCPO Box 3127, Makati City 1271, Philippines. Search for other works by this author on: Oxford Academic PubMed Google Scholar Michael B. Cohen, Michael B. Cohen 1Entomology and Plant Pathology Division, International Rice Research Institute, MCPO Box 3127, Makati City 1271, Philippines. Search for other works by this author on: Oxford Academic PubMed Google Scholar Fred Gould Fred Gould 2Department of Entomology, North Carolina State University, Raleigh, NC 27695–7634. Search for other works by this author on: Oxford Academic PubMed Google Scholar Environmental Entomology, Volume 29, Issue 5, 1 October 2000, Pages 972–978, https://doi.org/10.1603/0046-225X-29.5.972 Published: 01 October 2000 Article history Received: 16 November 1999 Accepted: 25 May 2000 Published: 01 October 2000
DA - 2000/10//
PY - 2000/10//
DO - 10.1603/0046-225X-29.5.972
VL - 29
IS - 5
SP - 972-978
SN - 0046-225X
KW - Bacillus thuringiensis
KW - Scirpophaga incertulas
KW - Chilo suppressalis
KW - resistance management
KW - dispersal
KW - rice
ER -
TY - JOUR
TI - Higher-level phylogeny of the Therevidae (Diptera : Insecta) based on 28S ribosomal and elongation factor-1 alpha gene sequences
AU - Yang, LL
AU - Wiegmann, BM
AU - Yeates, DK
AU - Irwin, ME
T2 - MOLECULAR PHYLOGENETICS AND EVOLUTION
AB - Therevidae (stilleto flies) are a little-known family of asiloid brachyceran Diptera (Insecta). Separate and combined phylogenetic analyses of 1200 bases of the 28S ribosomal DNA and 1100 bases of elongation factor-1α were used to infer phylogenetic relationships within the family. The position of the enigmatic taxon Apsilocephala Kröber is evaluated in light of the molecular evidence. In all analyses, molecular data strongly support the monophyly of Therevidae, excluding Apsilocephala, and the division of Therevidae into two main clades corresponding to a previous classification of the family into the subfamilies Phycinae and Therevinae. Despite strong support for some relationships within these groups, relationships at the base of the two main clades are weakly supported. Short branch lengths for Australasian clades at the base of the Therevinae may represent a rapid radiation of therevids in Australia.
DA - 2000/6//
PY - 2000/6//
DO - 10.1006/mpev.1999.0771
VL - 15
IS - 3
SP - 440-451
SN - 1095-9513
KW - Therevidae
KW - stiletto fly
KW - elongation factor-1 alpha
KW - 28S ribosomal DNA
KW - phylogeny
KW - Diptera
ER -
TY - JOUR
TI - High throughput cellular localization of specific plant mRNAs by liquid-phase in situ reverse transcription-polymerase chain reaction of tissue sections
AU - Koltai, H
AU - Bird, DM
T2 - PLANT PHYSIOLOGY
AB - Advances in high throughput DNA sequencing and bioinformatic gene discovery far outpace our ability to analyze gene function, necessitating development of more efficient means to examine expression at the cellular level. Here we present a polymerase chain reaction-based method to detect mRNA species in situ in which essentially all of the steps are carried out in liquid phase in a 96-well microtiter tray and only the final signal detection is performed on a microscope slide. We demonstrate the sensitivity of the method by the cellular localization of mRNA for the Tkn2 transcription factor in a wide variety of plant tissues, and its selectivity in discriminating a single gene family member by the in situ localization of rbcs3 transcripts. Furthermore, we demonstrate the utility of the in-well in situ method in detecting FDL and IFL1 transcripts in Arabidopsis sections, thus establishing the method as a tool to determine spatial expression pattern of sequences obtained from genomic sequencing projects. Being amenable to robotic processing, in-well in situ reverse transcription-polymerase chain reaction permits a great enhancement in the number of tissue samples that can be processed. Consequently, this method may become a powerful tool for functional genomics studies, permitting the cellular site of transcription of large numbers of sequences obtained from databases to be rapidly established.
DA - 2000/8//
PY - 2000/8//
DO - 10.1104/pp.123.4.1203
VL - 123
IS - 4
SP - 1203-1212
SN - 0032-0889
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033836945&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Heat shock protein HSP101 binds to the Fed-1 internal light regulatory element and mediates its high translational activity
AU - Ling, J
AU - Wells, DR
AU - Tanguay, RL
AU - Dickey, LF
AU - Thompson, WF
AU - Gallie, DR
T2 - PLANT CELL
AB - The internal light-regulatory element (iLRE) of ferredoxin (Fed-1) mRNA, comprising the 5' leader and at least the first 13 codons of the open reading frame, controls transcript abundance after illumination of the plant in a translation-dependent manner. We have characterized the RNA binding activities associated with the Fed-1 iLRE and have identified one activity as the heat shock protein HSP101, a protein shown to bind the 5' leader of tobacco mosaic virus. HSP101 was sufficient and necessary to mediate a high level of translational activity from a Fed-1 iLRE-containing mRNA in yeast. Moreover, the Fed-1 iLRE substantially enhanced translation of reporter mRNAs in plant protoplasts expressing HSP101. Expression of HSP101 was subject to developmental regulation in leaves in that expression was highest in young leaves. These data suggest that Fed-1 mRNA may use the HSP101 regulatory mechanism as a means of ensuring a high level of translation required for the light-mediated regulation of Fed-1 mRNA stability.
DA - 2000/7//
PY - 2000/7//
DO - 10.1105/tpc.12.7.1213
VL - 12
IS - 7
SP - 1213-1227
SN - 1532-298X
ER -
TY - JOUR
TI - Fertilizer management impacts on stand establishment, disease, and yield of Irish potato
AU - Crozier, CR
AU - Creamer, NG
AU - Cubeta, MA
T2 - POTATO RESEARCH
DA - 2000///
PY - 2000///
DO - 10.1007/BF02358513
VL - 43
IS - 1
SP - 49-59
SN - 1871-4528
KW - Solanum tuberosum L.
KW - soil fertility
KW - soluble salts
KW - plant spacing
KW - Rhizoctonia
ER -
TY - JOUR
TI - Effect of carbon and nitrogen sources on growth dynamics and exopolysaccharide production for the hyperthermophilic archaeon Thermococcus litoralis and bacterium Thermotoga maritima
AU - Rinker, KD
AU - Kelly, RM
T2 - BIOTECHNOLOGY AND BIOENGINEERING
AB - Batch and continuous cultures were used to compare specific physiological features of the hyperthermophilic archaeon, Thermococcus litoralis (T(opt) of 85 degrees to 88 degrees C), to another fermentative hyperthermophile that reduces S degrees facultatively, that is, the bacterium Thermotoga maritima (T(opt) of 80 degrees to 85 degrees C). Under nutritionally optimal conditions, these two hyperthermophiles had similar growth yields on maltose and similar cell formula weights based on elemental analysis: CH(1.7)O(0. 7)N(0.2)S(0.006) for T. litoralis and CH(1.6)O(0.6)N(0.2)S(0.005) for T. maritima. However, they differed with respect to nitrogen source, fermentation product patterns, and propensity to form exopolysaccharides (EPS). T. litoralis could be cultured in the absence or presence of maltose on an amino acid-containing defined medium in which amino acids served as the sole nitrogen source. T. maritima, on the other hand, did not utilize amino acids as carbon, energy, or nitrogen sources, and could be grown in a similar defined medium only when supplemented with maltose and ammonium chloride. Not only was T. litoralis unable to utilize NH(4)Cl as a nitrogen source, its growth was inhibited at certain levels. At 1 g/L ( approximately 20 mM) NH(4)Cl, the maximum growth yield (Y(x/s(max))) for T. litoralis was reduced to 13 g cells dry weight (CDW)/mol glucose from 40 g CDW/mol glucose in media lacking NH(4)Cl. Alanine production increased with increasing NH(4)Cl concentrations and was most pronounced if growth on NH(4)Cl was carried out in an 80% H(2) atmosphere. In T. maritima cultures, which would not grow in an 80% H(2) atmosphere, alanine and EPS were produced at much lower levels, which did not change with NH(4)Cl concentration. EPS production rose sharply at high dilution rates for both organisms, such that maltose utilization plots were biphasic. Wall growth effects were also noted, because cultures failed to wash out at dilution rates significantly above maximum growth rates determined from batch growth experiments. This study illustrates the importance of effective cultivation methods for addressing physiological issues related to the growth of hyperthermophilic heterotrophs.
DA - 2000/9/5/
PY - 2000/9/5/
DO - 10.1002/1097-0290(20000905)69:5<537::AID-BIT8>3.0.CO;2-7
VL - 69
IS - 5
SP - 537-547
SN - 0006-3592
KW - hyperthermophile
KW - archaea
KW - bioenergetics
KW - exopolysaccharide
KW - wall growth
ER -
TY - JOUR
TI - Dispersal by larvae of the stem borers Scirpophaga incertulas (Lepidoptera : Pyralidae) and Chilo suppressalis (Lepidoptera : Crambidae) in plots of transplanted rice
AU - Cohen, MB
AU - Romena, AM
AU - Gould, F
T2 - ENVIRONMENTAL ENTOMOLOGY
AB - We studied larval dispersal behavior of two rice stem borers, Scirpophaga incertulas (Walker) and Chilo suppressalis (Walker), to evaluate the potential of seed mixtures for resistance management in B. thuringiensis (Bt) rice. Both species showed extensive movement among plants (or “hills”) in plots of transplanted rice, during the course of larval development. On rice plants at the vegetative stage, almost all S. incertulas larvae dispersed on the day of eclosion. On plants at booting stage, most S. incertulas bored into hills on which egg masses were placed (referred to as the “release hill”). Almost all neonate C. suppressalis also bored into the release hill, at both vegetative and booting stages. At both rice growth stages, most larvae of both species dispersed to new hills between 7 and 18 d after eclosion. Both S. incertulas and C. suppressalis moved among tillers within the release hill, as indicated by an increase in dispersion among tillers over time. The distance and direction of dispersal of ballooning S. incertulas larvae was influenced by wind speed and direction. Larval recovery within plots generally declined rapidly over the first 5 d after egg hatch and then more slowly thereafter. Because many S. incertulas and C. suppressalis larvae move among tillers within hills and among hills within plots, many larvae in plots planted to seed mixtures will consume tissue from both Bt and non-Bt plants. This behavior will reduce the cumulative dose of toxin ingested and can accelerate the evolution of resistance.
DA - 2000/10//
PY - 2000/10//
DO - 10.1603/0046-225X-29.5.958
VL - 29
IS - 5
SP - 958-971
SN - 1938-2936
KW - Scirpophaga incertulas
KW - Chilo suppressalis
KW - larval dispersal
KW - resistance management
KW - rice
ER -
TY - JOUR
TI - Bacillus thuringiensis delta-endotoxin proteins show a correlation in toxicity and short circuit current inhibition against Helicoverpa zea
AU - Karim, S
AU - Gould, F
AU - Dean, DH
T2 - CURRENT MICROBIOLOGY
DA - 2000/9//
PY - 2000/9//
DO - 10.1007/s002840010122
VL - 41
IS - 3
SP - 214-219
SN - 1432-0991
ER -
TY - JOUR
TI - A general mixture model approach for mapping quantitative trait loci from diverse cross designs involving multiple inbred lines
AU - Liu, YF
AU - Zeng, ZB
T2 - GENETICAL RESEARCH
AB - Most current statistical methods developed for mapping quantitative trait loci (QTL) based on inbred line designs apply to crosses from two inbred lines. Analysis of QTL in these crosses is restricted by the parental genetic differences between lines. Crosses from multiple inbred lines or multiple families are common in plant and animal breeding programmes, and can be used to increase the efficiency of a QTL mapping study. A general statistical method using mixture model procedures and the EM algorithm is developed for mapping QTL from various cross designs of multiple inbred lines. The general procedure features three cross design matrices, W , that define the contribution of parental lines to a particular cross and a genetic design matrix, D , that specifies the genetic model used in multiple line crosses. By appropriately specifying W matrices, the statistical method can be applied to various cross designs, such as diallel, factorial, cyclic, parallel or arbitrary-pattern cross designs with two or multiple parental lines. Also, with appropriate specification for the D matrix, the method can be used to analyse different kinds of cross populations, such as F 2 backcross, four-way cross and mixed crosses (e.g. combining backcross and F 2 ). Simulation studies were conducted to explore the properties of the method, and confirmed its applicability to diverse experimental designs.
DA - 2000/6//
PY - 2000/6//
DO - 10.1017/S0016672300004493
VL - 75
IS - 3
SP - 345-355
SN - 0016-6723
ER -
TY - JOUR
TI - Role of neutrophils in intestinal mucosal injury
AU - Gayle, JM
AU - Blikslager, AT
AU - Jones, SL
T2 - JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION
DA - 2000/8/15/
PY - 2000/8/15/
DO - 10.2460/javma.2000.217.498
VL - 217
IS - 4
SP - 498-500
SN - 0003-1488
UR - http://europepmc.org/abstract/med/10953711
ER -
TY - JOUR
TI - Isozymatic diversity in the races of maize of the Americas
AU - Sanchez, J. J.
AU - Stuber, C. W.
AU - Goodman, M. M.
T2 - Maydica
DA - 2000///
PY - 2000///
VL - 45
IS - 3
SP - 185-203
ER -
TY - JOUR
TI - Heritability of tolerance to the Cry1Ab toxin of Bacillus thuringiensis in Chilo suppressalis (Lepidoptera : Crambidae)
AU - Alinia, F
AU - Cohen, MB
AU - Gould, F
T2 - JOURNAL OF ECONOMIC ENTOMOLOGY
AB - Heritability of Chilo suppressalis (Walker) tolerance to the Cry1Ab toxin of Bacillus thuringiensis Berliner was estimated using a half-sibling design. Artificial diet with and without Cry1Ab was infested with progenies of 20 males, each mated with 2 females, and mortality was scored 5 d after infestation. The progeny of each female was reared and scored separately. Mean mortality of the 20 families on the Cry1Ab diet was 46.5%. The effects of both male parent and of female parent within male parent were significant. Heritability was estimated to be 0.52, suggesting that a high proportion of phenotypic variation was because of genetic differences. Mortality on the Cry1Ab diet was not correlated with mortality on control diet, indicating that differences among families in tolerance to Cry1Ab were not attributable to differences in general fitness. Our results indicate that “high dose” Bt rice plants may be particularly important for Cry1Ab resistance management in C. suppressalis populations.
DA - 2000/2//
PY - 2000/2//
DO - 10.1603/0022-0493-93.1.14
VL - 93
IS - 1
SP - 14-17
SN - 0022-0493
KW - Bacillus thuringiensis
KW - Chilo suppressalis
KW - insecticide resistance
KW - heritability
KW - rice
ER -
TY - JOUR
TI - Determination of receptor binding properties of Bacillus thuringiensis delta-endotoxins to cotton bollworm (Helicoverpa zea) and pink bollworm (Pectinophora gossypiella) midgut brush border membrane vesicles
AU - Karim, S
AU - Riazuddin, S
AU - Gould, F
AU - Dean, DH
T2 - PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY
AB - Pesticidal activity and receptor binding properties of Bacillus thuringiensis toxins to cotton pink bollworm (Pectinophora gossypiella) and cotton bollworm (Helicoverpa zea) were investigated. P. gossypiella was susceptible to Cry1Aa, Cry1Ab, Cry1Ac, and Cry2Aa toxins. To H. zea, Cry1Ac and Cry1Ab were more potent than Cry1Aa and Cry2Aa. Cry1Ba, Cry1Ca, Cry1Da, Cry1Ea, Cry1Fa, Cry1Ga, Cry1Ha, and Cry2Ba were not potent against both pests. Binding assays were performed with 125I-labeled toxins (Cry1Aa, Cry1Ab, Cry1Ac, and Cry2Aa) and brush border membrane vesicles (BBMVs) prepared from H. zea and P. gossypiella midguts. Both Cry1Ab and Cry1Ac toxins showed saturable, high-affinity binding to P. gossypiella and H. zea BBMVs. Cry2Aa and Cry1Aa toxins bound to BBMVs with relatively low binding affinity but with high binding site concentration. Heterologous competition binding assays were performed to investigate the binding site cross reactivity. The results showed that Cry1Aa, Cry1Ab, and Cry1Ac recognize the same binding site, which is different from Cry2Aa. Ligand blot assay showed that Cry1Ac toxin binds to a 120-kDa BBMV protein in P. gossypiella and Cry1Ab binds to a major 210-kDa protein.
DA - 2000/7//
PY - 2000/7//
DO - 10.1006/pest.2000.2491
VL - 67
IS - 3
SP - 198-216
SN - 1095-9939
ER -
TY - JOUR
TI - A cytochrome P450 monooxygenase cDNA (CYP71A10) confers resistance to linuron in transgenic Nicotiana tabacum
AU - Siminszky, B
AU - Sheldon, BS
AU - Corbin, FT
AU - Dewey, RE
T2 - WEED SCIENCE
AB - The isolation of a Glycine max cytochrome P450 monooxygenase (P450) cDNA designated CYP71A10 that conferred linuron resistance to laboratory-grown, transgenic Nicotiana tabacum seedlings was previously reported. A nonsegregating transgenic N. tabacum line has been established that possesses two independent copies of the G. max CYP71A10 transgene. Five-week-old progeny plants of this selected line were grown in a controlled environmental chamber and treated with linuron using either pretransplant incorporated (PTI) or postemergence (POST) applications. CYP71A10-transformed N. tabacum was more tolerant to linuron than the wild type for both application methods. The transgenic N. tabacum line tolerated an approximately 16-fold and 12-fold higher rate of linuron than wild-type N. tabacum when the herbicide was applied PTI or POST, respectively. These results provide evidence that plant-derived P450 genes can be employed effectively to confer herbicide resistance to transgenic plants.
DA - 2000///
PY - 2000///
DO - 10.1614/0043-1745(2000)048[0291:ACPMCC]2.0.CO;2
VL - 48
IS - 3
SP - 291-295
SN - 0043-1745
KW - cytochrome P450
KW - linuron
KW - Glycine max L. Merr 'Dare', soybean
KW - Nicotiana tabacum L. 'SR1', tobacco
KW - herbicide metabolism
KW - phenylurea
KW - genetic engineering
KW - metabolic engineering
ER -
TY - JOUR
TI - Variation in performance on cry1Ab-transformed and nontransgenic rice varieties among populations of Scirpophaga incertulas (Lepidoptera : Pyralidae) from Luzon Island, Philippines
AU - Bentur, JS
AU - Cohen, MB
AU - Gould, F
T2 - JOURNAL OF ECONOMIC ENTOMOLOGY
AB - We quantified variation in performance under greenhouse conditions among seven populations of Scirpophaga incertulas (Walker) from Luzon Island, Philippines, on three rice varieties: 'IR58' transformed with the cry1Ab gene from Bacillus thuringiensis Berliner, and nontransgenic IR58 and IR62. On IR62, S. incertutas performance did not differ among provinces for any of the 10 parameters measured, but there was a significant effect of town within province for one parameter, 20-d-old larval weight. Larval survival after 48 h on cy1Ab-transformed IR58 did not differ significantly among provinces, but did differ significantly among towns within a province. There was no geographic variation in larval survival after 48 h on control plants of IR58. Surviving insects from the cry1Ab-transformed IR58 were transferred to IR62 to complete development. There was no geographic variation in the percentage of insects completing development to adult emergence and the time required by the transferred female insects to complete development. However, there was variation among provinces in male developmental time. The absence of geographic variation on nontransgenic IR58 and the very limited variation on IR62 indicated that there was little variation in general vigor among the S. incertulas populations and thus that the variation in performance oil cry1Ab-transformed IR58 was probably attributable to differences in susceptibility to Cry1Ab.
DA - 2000/12//
PY - 2000/12//
DO - 10.1603/0022-0493-93.6.1773
VL - 93
IS - 6
SP - 1773-1778
SN - 0022-0493
KW - Scirpophaga incertulas
KW - Bacillus thuringiensis
KW - rice
KW - resistance management
ER -
TY - JOUR
TI - Variation among maize inbred lines and detection of quantitative trait loci for growth at low phosphorus and responsiveness to arbuscular mycorrhizal fungi
AU - Kaeppler, SM
AU - Parke, JL
AU - Mueller, SM
AU - Senior, L
AU - Stuber, C
AU - Tracy, WF
T2 - CROP SCIENCE
AB - Maize ( Zea mays L.) growth at low soil P levels is affected both by inherent physiological factors as well as interactions with soil microbes. The objectives of this study were (i) to quantify differences among maize inbred lines for growth at low P and response to mycorrhizal fungi, and (ii) to identify quantitative trait loci (QTL) controlling these traits in a B73 × Mo17 recombinant inbred population. Shoot dry weight and root volume were measured in the greenhouse after 6 wk of growth in a factorial experiment of 28 inbred maize lines using treatments of low vs. high P and mycorrhizal vs. nonmycorrhizal treatments. Shoot dry weight for the low P treatment in the absence of mycorrhizae ranged from 0.56 to 3.15 g. Mycorrhizal responsiveness based on shoot dry weight ranged from 106 to 800%. Shoot dry weight in the low P–nonmycorrhizal treatment was highly negatively correlated with mycorrhizal responsiveness. Plants grown at high P in the presence of mycorrhizae accumulated only 88% of the biomass of plants grown at high P in the absence of mycorrhizae, indicating that mycorrhizae can reduce plant growth when not contributing to the symbiosis. Percentage of root colonization was not correlated with mycorrhizal responsiveness. B73 and Mo17 were among the extremes for growth at low P and mycorrhizal responsiveness, and a B73 × Mo17 population of 197 recombinant inbred lines was used to detect QTL for growth at low P and mycorrhizal responsiveness. Three QTL were identified which controlled growth at low P in the absence of mycorrhizae based on shoot weight and one QTL which controlled mycorrhizal responsiveness. This study indicates that there is substantial variation among maize lines for growth at low P and response to mycorrhizal fungi. This variation could be harnessed to develop cultivars for regions of the world with P deficiency and for reduced‐input production systems.
DA - 2000///
PY - 2000///
DO - 10.2135/cropsci2000.402358x
VL - 40
IS - 2
SP - 358-364
SN - 1435-0653
ER -
TY - JOUR
TI - Pest control by the release of insects carrying a female-killing allele on multiple loci
AU - Schliekelman, P
AU - Gould, F
T2 - JOURNAL OF ECONOMIC ENTOMOLOGY
AB - With recent advances in genetics, many new strategies for pest control have become feasible. This is the second article in which we model new techniques for pest control based on the mass release of genetically modified insects. In this article we model the release of insects carrying a dominant and redundant female killing or sterilizing (FK) allele on multiple genetic loci. If such insects are released into a target population, the FK allele can become widely spread in the population through the males while reducing the population each generation by killing females. We allow the number of loci used to vary from 1 to 20. We also allow the FK allele to carry a fitness cost in males due to the gene insertions. Using a model, we explore the effectiveness and optimal strategies for such releases. In the most ideal circumstances (no density-dependence and released insects equal in fitness to wild ones), FK releases are several orders of magnitude more effective than equal sized sterile male releases. For example, a single release of 19 FK-bearing males for every two wild males, with the released males carrying the FK allele on 10 loci, reduces the target population to 0.002% of no-release size. An equal sized sterile release reduces the target population to 5% of no-release size. We also show how the effectiveness of the technique decreases as the fitness cost of the FK alleles in males increases. For example, the above mentioned release reduces the target population to 0.7% of no-release size if each FK allele carries a fitness cost in males of 5%. Adding a simple model for density-dependence and assuming that each of the released males carries the FK allele on six loci, we show that the release size necessary to reduce the target population to 1/100 of no-release size in 10 generations of releases varies from 0.44:1 to 4:1 (depending on parameter values). We also calculate the optimal number of loci on which to put the FK allele under various circumstances.
DA - 2000/12//
PY - 2000/12//
DO - 10.1603/0022-0493-93.6.1566
VL - 93
IS - 6
SP - 1566-1579
SN - 0022-0493
KW - genetic control
KW - sterile insect technique
KW - multilocus
KW - female-killing autocidal
ER -
TY - JOUR
TI - Pest control by the introduction of a conditional lethal trait on multiple loci: Potential, limitations, and optimal strategies
AU - Schliekelman, P
AU - Gould, F
T2 - JOURNAL OF ECONOMIC ENTOMOLOGY
AB - Advances in genetics have made it feasible to genetically engineer insect strains carrying a conditional lethal trait on multiple loci. We model the release into a target pest population of insects carrying a dominant and fully penetrant conditional lethal trait on 1-20 loci. Delaying the lethality for several generations after release allows the trait to become widely spread in the target population before being activated. To determine effectiveness and optimal strategies for such releases, we vary release size, number of generations until the conditional lethality, nonconditional fitness cost resulting from gene insertions, and fitness reduction associated with laboratory rearing. We show that conditional lethal releases are potentially orders of magnitude more effective than sterile male releases of equal size, and that far smaller release sizes may be required for this approach than necessary with sterile males. For example, a release of male insects carrying a conditional lethal allele that is activated in the F4 generation on 10 loci reduces the target populatioin to 10(-4) of no-release size if there are initially two released males for every wild male. We show how the effectiveness of conditional lethal releases decreases as the nonconditional fitness reduction (i.e., fitness reduction before the trait becomes lethal) associated with the conditional lethal genes increases. For example, if there is a 5% nonconditional fitness cost per conditional lethal allele, then a 2:1 (released male:wild male) release with conditional lethal alleles that are activated in the F4 generation reduces the population to 2-5% (depending on the degree of density dependence) of the no-release size. If there is a per-allele reduction in fitness, then as the number of loci is increased there is a trade-off between the fraction of offspring carrying at least one conditional lethal allele and the fitness of the released insects. We calculate the optimal number of loci on which to insert the conditional lethal gene given various conditions. In addition, we show how laboratory-rearing fitness costs, density-dependence, and all-male versus male-female releases affect the efficiency of conditional lethal releases.
DA - 2000/12//
PY - 2000/12//
DO - 10.1603/0022-0493-93.6.1543
VL - 93
IS - 6
SP - 1543-1565
SN - 0022-0493
KW - conditional lethal
KW - genetic control
KW - multilocus
KW - sterile male
KW - model
ER -
TY - JOUR
TI - Numerical simulation of the effect of thermal dispersion on forced convection in a circular duct partly filled with a Brinkman-Forchheimer porous medium
AU - Kuznetsov, AV
AU - Xiong, M
T2 - INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW
AB - A numerical simulation of the fully developed forced convection in a circular duct partly filled with a fluid saturated porous medium is presented. The Brinkman‐Forchheimer‐extended Darcy equation is used to describe the fluid flow in the porous region. The energy equation for the porous region accounts for the effect of thermal dispersion. The dependence of the Nusselt number on a number of parameters, such as the Reynolds number, the Darcy number, the Forchheimer coefficient, as well as the thickness of the porous region is investigated. The numerical results obtained in this research are in agreement with published experimental data.
DA - 2000///
PY - 2000///
DO - 10.1108/09615530010338169
VL - 10
IS - 5-6
SP - 488-501
SN - 1758-6585
KW - numerical simulation
KW - porous media
KW - thermal dispersion
ER -
TY - JOUR
TI - Molecular phylogenetics of the holly leaf miners (Diptera : Agromyzidae : Phytomyza): Species limits, speciation, and dietary specialization
AU - Scheffer, SJ
AU - Wiegmann, BM
T2 - MOLECULAR PHYLOGENETICS AND EVOLUTION
AB - A molecular phylogenetic analysis was conducted to determine relationships and to investigate character evolution in the Phytomyza ilicis group of leafmining flies on hollies (Aquifoliaceae: Ilex). A total of 2207 bp of the mitochondrial cytochrome oxidase I and II genes were sequenced for all known holly leafminers, as well as for several undescribed members of this group. Maximum-parsimony analysis of the sequence data indicates that these leafminers form a monophyletic group with the inclusion of an undescribed leafminer that feeds on the distantly related plant Gelsemium sempevirens (Loganiaceae). Species boundaries of previously known and of undescribed holly leafmining species were confirmed with the molecular data, with one exception. Optimization of variable ecological and morphological characters onto the most parsimonious phylogeny suggests that these traits are evolutionarily labile, requiring multiple instances of convergence and/or reversal to explain their evolutionary history. Speciation in holly leafminers is associated with host shifts and appears to involve colonization of new hosts more often than cospeciation as the hosts diverge. Monophagy is the most common feeding pattern in holly leafminers, and more generalized feeding is inferred to have evolved at least two separate times, possibly as a prelude to speciation.
DA - 2000/11//
PY - 2000/11//
DO - 10.1006/mpev.2000.0830
VL - 17
IS - 2
SP - 244-255
SN - 1095-9513
ER -
TY - PAT
TI - Increasing expression of transgenes in plant cells using insulator elements
AU - Thompson, W.
AU - Allen, G.
AU - Mankin, S.
C2 - 2000///
DA - 2000///
PY - 2000///
ER -
TY - JOUR
TI - Genetic mapping of a fusarium wilt resistance gene (Fom-2) in melon (Cucumis melo L.)
AU - Wang, YH
AU - Thomas, CE
AU - Dean, RA
T2 - MOLECULAR BREEDING
DA - 2000/8//
PY - 2000/8//
DO - 10.1023/A:1009671925793
VL - 6
IS - 4
SP - 379-389
SN - 1380-3743
KW - AFLP
KW - co-dominant markers
KW - Cucumis melo
KW - fusarium wilt
KW - marker-assisted selection
ER -
TY - PAT
TI - Cytochrome P-450 constructs and method of producing herbicide-resistant transgenic plants
AU - Siminszky, B.
AU - Dewey, R.
AU - Corbin, F.
C2 - 2000///
DA - 2000///
PY - 2000///
ER -
TY - JOUR
TI - Comparison of two computer techniques and a visual technique for the estimation of wheat leaf consumption by cereal leaf beetle (Coleoptera : Chrysomelidae)
AU - Sorenson, CE
AU - Ihrig, RA
AU - Bradley, , JR
AU - Van Duyn, JW
AU - Herbert, DA
T2 - JOURNAL OF ENTOMOLOGICAL SCIENCE
AB - Three techniques for estimating wheat foliage defoliation by cereal leaf beetle, Oulema melanopus (L.), larvae were evaluated. The techniques were visual estimation, computer estimation with image capture through a flatbed scanner (Lanalyze), and a commercially available video computer image analysis system (CIAS). Both computer-assisted techniques exhibited high levels of repeatability. Both consistently produced errors of less than 3 percent, although each system exhibited different error patterns. The Lanalyze system tended to systematically underestimate actual defoliation of mock leaves, while the CIAS system tended to overestimate actual defoliation. Visual estimators exhibited greater variation among estimates and, on average, greater discrepancies from actual defoliation when compared with the computer assisted techniques. The experience of the observer had a bearing on the accuracy and consistency of visual estimates; more experienced observers had the best accuracy.
DA - 2000/10//
PY - 2000/10//
DO - 10.18474/0749-8004-35.4.391
VL - 35
IS - 4
SP - 391-401
SN - 0749-8004
KW - defoliation estimation
KW - cereal leaf beetle
KW - Oulema melanopus
KW - visual estimation
KW - image analysis
ER -
TY - JOUR
TI - Androgenic regulation of steroid hormone receptor mRNAs in the brain of whiptail lizards
AU - Hartman, Godwin J.
AU - Nag, V.
AU - P.
AU - Crews, D.
T2 - Journal of Neuroendocrinology
AB - Sex and species differences in androgenic regulation of steroid hormone receptor mRNAs were examined in the diencephalon of two species of whiptail lizards: Cnemidophorus inornatus is a sexual species and the direct evolutionary ancestor to Cnemidophorus uniparens , an all‐female parthenogenetic species. Lizards were gonadectomized and treated with different doses of either aromatizable testosterone or nonaromatizable dihydrotestosterone. The relative abundances of androgen‐, oestrogen‐, and progesterone‐receptor mRNAs were compared in various nuclei following in situ hybridization with homologous riboprobes. A diversity of patterns in androgenic regulation was observed, with effects differing according to brain region, the steroid‐receptor mRNA being considered and, in some cases, between androgens. In the ancestral sexual species, intact males had lower androgen‐receptor mRNA abundances than castrated, blank‐implanted males in the medial preoptic area. Testosterone significantly decreased androgen‐receptor mRNA abundance in the medial preoptic area of castrated males. Males had higher androgen‐receptor mRNA levels in the preoptic area than females generally and neither the sexual or parthenogenetic females showed a decrease in androgen‐receptor mRNA with androgen treatment. Both testosterone and dihydrotestosterone increased oestrogen‐receptor mRNA abundance in the ventromedial hypothalamus of C. inornatus , but no sex differences in this effect were observed. Gonadectomy decreased, whereas androgen treatment increased, progesterone‐receptor mRNA abundance in the ventromedial hypothalamus. There was a sex difference in this response to androgen in the sexual species, with males having greater amounts than females in this brain area. The parthenogenetic species exhibited a similar pattern to females of the sexual species, but the levels were higher overall, possibly because Cnemidophorus uniparens is triploid. The periventricular preoptic area showed a different pattern, with testosterone treatment increasing progesterone‐receptor mRNA abundance in both sexes of the sexual species and in the parthenogenetic species, while dihydrotestosterone did not. The diversity of patterns in androgen effects indicates that gonadal sex, aromatization of androgen, and perhaps gene dosage all influence the expression of steroid‐receptor mRNAs in the lizard brain.
DA - 2000///
PY - 2000///
DO - 10.1046/j.1365-2826.2000.00513.x
VL - 12
IS - 2000
SP - 599–606
ER -
TY - JOUR
TI - Registration of NC97BGTAB9 and NC97BGTAB10 wheat germplasm lines resistant to powdery mildew
AU - Navarro, R. A.
AU - Murphy, J. P.
AU - Leath, S.
AU - Shi, A.
T2 - Crop Science
DA - 2000///
PY - 2000///
VL - 40
IS - 5
SP - 1508-1509
ER -
TY - JOUR
TI - Monophyly and relationships of the Tabanomorpha (Diptera : Brachycera) based on 28S ribosomal gene sequences
AU - Wiegmann, BM
AU - Tsaur, SC
AU - Webb, DW
AU - Yeates, DK
AU - Cassel, BK
T2 - ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA
AB - Higher-level relationships among the earliest lineages of brachyceran Diptera remain poorly resolved by comparative morphology. Nucleotide sequence data should be useful in clarifying brachyceran relationships, especially where morphological evidence is either contradictory or controversial. We examined phylogenetic relationships among the family-level taxa of the brachyceran infraorder Tabanomorpha using sequences of a large portion of the 28S ribosomal DNA. Twenty-five species were sequenced, including five outgroup species from the Stratiomyomorpha and Xylophagomorpha. Parsimony and maximum likelihood-based phylogenetic analysis of 2,371 alignable sites yielded identical inferred tree topologies. 28S rDNA supports the monophyly of the Tabanomorpha (Vermileonidae, Rhagionidae, Pelecorhynchidae, Athericidae and Tabanidae). Our results contradict several published hypotheses that associate Vermileonidae with asiloid or eremoneuran taxa remote from the Tabanomorpha. The molecular data also support monophyly for all of the included family-level lineages, and corroborate several recent phylogenetic hypotheses based on comparative morphology.
DA - 2000/9//
PY - 2000/9//
DO - 10.1603/0013-8746(2000)093[1031:MAROTT]2.0.CO;2
VL - 93
IS - 5
SP - 1031-1038
SN - 1938-2901
KW - Tabanomorpha
KW - Tabanidae
KW - phylogeny
KW - 28S ribosomal DNA
KW - molecular systematics
ER -
TY - JOUR
TI - Investigation of the effect of transverse thermal dispersion on forced convection in porous media
AU - Kuznetsov, AV
T2 - ACTA MECHANICA
DA - 2000///
PY - 2000///
DO - 10.1007/BF01453643
VL - 145
IS - 1-4
SP - 35-43
SN - 1619-6937
ER -
TY - JOUR
TI - Integration of repellents, attractants, and insecticides in a "push-pull" strategy for managing German cockroach (Dictyoptera : Blattellidae) populations
AU - Nalyanya, G
AU - Moore, CB
AU - Schal, C
T2 - JOURNAL OF MEDICAL ENTOMOLOGY
DA - 2000/5//
PY - 2000/5//
DO - 10.1603/0022-2585(2000)037[0427:IORAAI]2.0.CO;2
VL - 37
IS - 3
SP - 427-434
SN - 1938-2928
KW - Blattella germanica
KW - German cockroach
KW - repellent
KW - attractant
KW - methyl neoalkanamide
ER -
TY - PAT
TI - Insecticide resistance assay
AU - Roe, R. M.
AU - Bailey, W. D.
AU - Gould, F.
AU - Kennedy, G. G.
C2 - 2000///
DA - 2000///
PY - 2000///
ER -
TY - JOUR
TI - Heartworm infection in cats: 50 cases (1985-1997)
AU - Atkins, CE
AU - DeFrancesco, TC
AU - Coats, , JR
AU - Sidley, JA
AU - Keene, BW
T2 - JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION
AB - To characterize risk factors, clinical findings, usefulness of diagnostic tests, and prognosis in cats with naturally occurring heartworm infection (HWI).Retrospective study.50 cats with Dirofilaria immitis infection.Medical records, thoracic radiographs, and echocardiograms were reviewed and findings compared with appropriate reference populations.Findings suggested that male cats were not predisposed to HWI, domestic shorthair cats were at increased risk, and indoor housing was only partially protective. Fewer cases of HWI were identified in the final quarter of the year, compared with other periods, and prevalence is not apparently increasing. Signs of respiratory tract disease were most common, followed by vomiting. Infection was diagnosed incidentally in > 25% of cats; conversely, 10% of infected cats died suddenly without other clinical signs. Serologic tests were most useful for diagnosis, followed by radiography and echocardiography. Eosinophilia supported the diagnosis. Overall median survival time was 1.5 years but exceeded 4 years in cats surviving beyond the day of diagnosis.Sex does not appear to be a risk factor for HWI in cats, and indoor housing provides only incomplete protection. Signs of respiratory tract disease (dyspnea and cough) are the strongest indicators of HWI in cats, and some radiographic evidence of infection is detected in most cases. Antibody screening for HWI in cats is efficacious, and antigen testing and echocardiography are most useful for making a definitive antemortem diagnosis.
DA - 2000/8/1/
PY - 2000/8/1/
DO - 10.2460/javma.2000.217.355
VL - 217
IS - 3
SP - 355-358
ER -
TY - JOUR
TI - Genetic variation in the Myzus persicae complex (Homoptera : Aphididae): Evidence for a single species
AU - Clements, KM
AU - Wiegmann, BM
AU - Sorenson, CE
AU - Smith, CF
AU - Neese, PA
AU - Roe, RM
T2 - ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA
AB - Journal Article Genetic Variation in the Myzus persicae Complex (Homoptera: Aphididae): Evidence for a Single Species Get access Kieran M Clements, Kieran M Clements Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647 Search for other works by this author on: Oxford Academic Google Scholar Brian M Wiegmann, Brian M Wiegmann Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647 Search for other works by this author on: Oxford Academic Google Scholar Clyde E Sorenson, Clyde E Sorenson Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647 Search for other works by this author on: Oxford Academic Google Scholar Clyde F Smith, Clyde F Smith Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647 Search for other works by this author on: Oxford Academic Google Scholar Paul A Neese, Paul A Neese Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647 Search for other works by this author on: Oxford Academic Google Scholar R Michael Roe R Michael Roe Department of Entomology, North Carolina State University, Raleigh, NC 27695–7647. To whom correspondence should be addressed: Dearstyne Entomology Building, Box 7647, W. Ligon Street Extension, North Carolina State University, Raleigh, NC 27695-7647. Fax: 919-515-4325, michael_roe@ncsu.edu Search for other works by this author on: Oxford Academic Google Scholar Annals of the Entomological Society of America, Volume 93, Issue 1, 1 January 2000, Pages 31–46, https://doi.org/10.1603/0013-8746(2000)093[0031:GVITMP]2.0.CO;2 Published: 01 January 2000 Article history Accepted: 06 July 1999 Published: 01 January 2000
DA - 2000/1//
PY - 2000/1//
DO - 10.1603/0013-8746(2000)093[0031:GVITMP]2.0.CO;2
VL - 93
IS - 1
SP - 31-46
SN - 1938-2901
KW - Myzus nicotianae
KW - Myzus persicae
KW - cytochrome oxidase II
KW - elongation factor-1 alpha (EF-1 alpha)
ER -
TY - JOUR
TI - Geminiviruses: Models for plant DNA replication, transcription, and cell cycle regulation
AU - Hanley-Bowdoin, L.
AU - Settlage, S. B.
AU - Orozco, B. M.
AU - Nagar, S.
AU - Robertson, D.
T2 - Critical Reviews in Biochemistry and Molecular Biology
DA - 2000///
PY - 2000///
VL - 35
IS - 2
SP - 105-140
ER -
TY - JOUR
TI - Differential responses of Central American and Mexican pine species and Pinus radiata to infection by the pitch canker fungus
AU - Hodge, GR
AU - Dvorak, WS
T2 - NEW FORESTS
DA - 2000/5//
PY - 2000/5//
DO - 10.1023/A:1006613021996
VL - 19
IS - 3
SP - 241-258
SN - 1573-5095
KW - genetic variation
KW - tree breeding
KW - gene conservation
KW - disease resistance
KW - forest pathology
KW - Fusarium
KW - pitch canker
ER -
TY - PCOMM
TI - Consentience on the necessity of Juvenile Hormone for vitellogenesis in the German cockroach - Reply
AU - Holbrook, GL
AU - Bachmann, JA
AU - Schal, C
AB - Physiological EntomologyVolume 25, Issue 3 p. 208-210 Reply − Consentience on the necessity of Juvenile Hormone for vitellogenesis in the German cockroach G. L. Holbrook, G. L. Holbrook Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this authorJ. A. Bachmann, J. A. Bachmann Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this authorC. Schal, C. Schal Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this author G. L. Holbrook, G. L. Holbrook Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this authorJ. A. Bachmann, J. A. Bachmann Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this authorC. Schal, C. Schal Department of Entomology, Pennsylvania State University, University Park, PA 16802, U.S.A. Search for more papers by this author First published: 25 December 2001 https://doi.org/10.1046/j.1365-3032.2000.00199-1.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Volume25, Issue3September 2000Pages 208-210 RelatedInformation
DA - 2000/9//
PY - 2000/9//
DO - 10.1046/j.1365-3032.2000.00199-1.x
SP - 208-210
ER -
TY - JOUR
TI - Chromosome condensation induced by geminivirus infection of mature plant cells
AU - Bass, H. W.
AU - Nagar, S.
AU - Hanley-Bowdoin, L.
AU - Robertson, D.
T2 - Journal of Cell Science
DA - 2000///
PY - 2000///
VL - 113
IS - 7
SP - 1149-1160
ER -
TY - JOUR
TI - A geminivirus replication protein interacts with the retinoblastoma protein through a novel domain to determine symptoms and tissue specificity of infection in plants
AU - Kong, LJ
AU - Orozco, BM
AU - Roe, JL
AU - Nagar, S
AU - Ou, S
AU - Feiler, HS
AU - Durfee, T
AU - Miller, AB
AU - Gruissem, W
AU - Robertson, D
AU - Hanley-Bowdoin, L
T2 - EMBO JOURNAL
AB - Geminiviruses replicate in nuclei of mature plant cells after inducing the accumulation of host DNA replication machinery. Earlier studies showed that the viral replication factor, AL1, is sufficient for host induction and interacts with the cell cycle regulator, retinoblastoma (pRb). Unlike other DNA virus proteins, AL1 does not contain the pRb binding consensus, LXCXE, and interacts with plant pRb homo logues (pRBR) through a novel amino acid sequence. We mapped the pRBR binding domain of AL1 between amino acids 101 and 180 and identified two mutants that are differentially impacted for AL1-pRBR interactions. Plants infected with the E-N140 mutant, which is wild-type for pRBR binding, developed wild-type symptoms and accumulated viral DNA and AL1 protein in epidermal, mesophyll and vascular cells of mature leaves. Plants inoculated with the KEE146 mutant, which retains 16% pRBR binding activity, only developed chlorosis along the veins, and viral DNA, AL1 protein and the host DNA synthesis factor, proliferating cell nuclear antigen, were localized to vascular tissue. These results established the importance of AL1-pRBR interactions during geminivirus infection of plants.
DA - 2000/7/3/
PY - 2000/7/3/
DO - 10.1093/emboj/19.13.3485
VL - 19
IS - 13
SP - 3485-3495
SN - 0261-4189
KW - AL1
KW - cell cycle
KW - differentiation
KW - plant DNA virus
KW - pRb
ER -
TY - JOUR
TI - Testing Bt refuge strategies in the field
AU - Gould, F
T2 - NATURE BIOTECHNOLOGY
DA - 2000/3//
PY - 2000/3//
DO - 10.1038/73693
VL - 18
IS - 3
SP - 266-267
SN - 1087-0156
ER -
TY - JOUR
TI - Subtilisins of Bacillus spp. hydrolyze keratin and allow growth on feathers
AU - Evans, KL
AU - Crowder, J
AU - Miller, ES
T2 - CANADIAN JOURNAL OF MICROBIOLOGY
DA - 2000/11//
PY - 2000/11//
DO - 10.1139/cjm-46-11-1004
VL - 46
IS - 11
SP - 1004-1011
SN - 0008-4166
KW - keratin hydrolysis
KW - Bacillus
KW - subtilisin
KW - keratinase
ER -
TY - JOUR
TI - New frontiers in the study of dispersal and spatial analysis of epidemics caused by species in the genus Phytophthora
AU - Ristaino, JB
AU - Gumpertz, ML
T2 - ANNUAL REVIEW OF PHYTOPATHOLOGY
AB - Diseases caused by species in the genus Phytophthora are responsible for significant economic losses on a wide range of host plants. Spatial pattern is one of the most characteristic ecological properties of a species, and reflects environmental and genetic heterogeneity and reproductive population growth acting on the processes of reproduction, dispersal, and mortality. Species of Phytophthora can be dispersed either in soil, via surface water movement down rows, from rain splash dispersal, by air, or via movement by humans or invertebrate activity. Dispersal results in patchiness in patterns of disease or inoculum in soil. In this chapter we discuss the mechanisms of dispersal of members of this important genus and describe several methods that can be used to statistically analyze data for which spatial coordinates are known. The methods include testing spatial autocorrelation for binary data or continuous data, semivariograms, and regression models for spatial data. The goal of spatial pattern analysis is to gain an understanding of the mechanisms of dispersal of propagules and to sort out the physical and biological factors that are important for spread of plant pathogens and ultimately, for disease management.
DA - 2000///
PY - 2000///
DO - 10.1146/annurev.phyto.38.1.541
VL - 38
IS - 2000
SP - 541-+
SN - 1545-2107
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033748429&partnerID=MN8TOARS
KW - dispersal
KW - epidemiology
KW - management
KW - molecular epidemiology
KW - spatial pattern analysis
KW - Phytophthora diseases
ER -
TY - JOUR
TI - Isozymatic and morphological diversity in the races of maize of Mexico
AU - Sanchez, JJ
AU - Goodman, MM
AU - Stuber, CW
T2 - ECONOMIC BOTANY
DA - 2000///
PY - 2000///
DO - 10.1007/BF02866599
VL - 54
IS - 1
SP - 43-59
SN - 1874-9364
KW - Zea mays L.
KW - isozymes
KW - genetic diversity
KW - genetic differentiation
ER -
TY - JOUR
TI - Influence of soil calcium, potassium, and pH on development of leaf tipburn of cabbage in eastern North Carolina
AU - Cubeta, MA
AU - Cody, BR
AU - Sugg, RE
AU - Crozier, CR
T2 - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS
AB - Abstract Three hypotheses that involved manipulation of soil calcium (Ca), potassium (K), and pH in relation to the occurrence of leaf tipburn of cabbage in eastern North Carolina (NC) were formulated and tested: 1) adding K to soil will increase (induce) leaf tipburn; 2) adding Ca and K together to soil will block K‐related tipburn induction, and 3) raising soil pH to levels of 6.0 to 6.5 will decrease leaf tipburn. Six experiments were conducted in commercial cabbage production fields in eastern NC in 1996 and 1997 to test these hypotheses. Hypothesis 1 was accepted since higher rates of K significantly (p<0.05) increased leaf K concentration, soil K content and leaf tipburn incidence compared with the control. Total cabbage yield increased as K rates increased, however, significant differences were only observed between the control and the highest rate (365 kg K ha‐1) in 1996. Hypothesis 2 was accepted since adding increased amounts of Ca and K. did not significantly increase leaf tipburn incidence. Hypothesis 3 was rejected since a range of soil pH from 5.3 to 6.6 did not increase or decrease leaf tipburn incidence, nutrient uptake or total yield. These data suggest that leaf tipburn of cabbage can be increased (induced) with excessive K fertilization and that this practice may be associated with the disorder observed in NC. Also, the addition of Ca with K may potentially reduce the risk associated with K‐related leaf tipburn of cabbage.
DA - 2000///
PY - 2000///
DO - 10.1080/00103620009370435
VL - 31
IS - 3-4
SP - 259-275
SN - 1532-2416
ER -
TY - JOUR
TI - Fluid flow and heat transfer analysis of Couette flow in a composite duct
AU - Kuznetsov, AV
T2 - ACTA MECHANICA
DA - 2000///
PY - 2000///
DO - 10.1007/BF01182508
VL - 140
IS - 3-4
SP - 163-170
SN - 0001-5970
ER -
TY - JOUR
TI - Epistatic repression of PHANTASTICA and class 1 KNOTTED genes is uncoupled in tomato
AU - Koltai, H
AU - Bird, DM
T2 - PLANT JOURNAL
AB - Summary Class 1 KNOTTED genes ( KNOX ) and PHANTASTICA ( PHAN ) are both central to meristem establishment and maintenance and, in maize and Antirrhinum , it has been proposed that PHAN acts as an epigenetic repressor of KNOX . In tomato, a distinct spatial distribution of Tkn2 KNOX transcripts compared to Antirrhinum and maize suggests either a different spatial distribution of tomato PHAN ( Le‐phan ) transcripts, or that PHAN alone is insufficient for KNOX repression in tomato. We established the pattern of Le‐phan expression, including a first demonstration of PHAN expression in healthy roots, and found Le‐phan and Tkn2 transcripts to be temporally and spatially coincidental, with PHAN exhibiting an expression pattern in tomato distinct from that in plants with simple leaves. Our results imply that the expression of Le‐phan is insufficient for the repression of Tkn2 in tomato and suggest an expanded role for either gene in the establishment of cell identity in plant development.
DA - 2000/6//
PY - 2000/6//
DO - 10.1046/j.1365-313X.2000.00754.x
VL - 22
IS - 5
SP - 455-459
SN - 0960-7412
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034086796&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Differential expression of genes encoding cell wall proteins in vascular tissues from vertical and bent loblolly pine trees
AU - Zhang, Y.
AU - Sederoff, R. R.
AU - Allona, I.
T2 - Tree Physiology
DA - 2000///
PY - 2000///
VL - 20
IS - 7
SP - 457-466
ER -
TY - JOUR
TI - Cuticular hydrocarbons of the dampwood termite, Zootermopsis nevadensis: Caste differences and role of lipophorin in transport of hydrocarbons and hydrocarbon metabolites
AU - Sevala, VL
AU - Bagneres, AG
AU - Kuenzli, M
AU - Blomquist, GJ
AU - Schal, C
T2 - JOURNAL OF CHEMICAL ECOLOGY
DA - 2000/3//
PY - 2000/3//
DO - 10.1023/A:1005440624678
VL - 26
IS - 3
SP - 765-789
SN - 0098-0331
KW - lipophorin
KW - hydrocarbon
KW - termite
KW - Isoptera
KW - castes
KW - cuticle
KW - metabolism
ER -
TY - JOUR
TI - Commercial fungicide formulations induce in vitro oospore formation and phenotypic change in mating type in Phytophthora infestans
AU - Groves, CT
AU - Ristaino, JB
T2 - PHYTOPATHOLOGY
AB - A wide range of commercially formulated fungicides cause in vitro effects on mating behavior in specific isolates of Phytophthora infestans, the causal agent of late blight of potato and tomato. Four isolates of P. infestans representing each of the four common US genotypes, US-1, US-6, US-7, and US-8 and varying in their sensitivity to metalaxyl, were exposed to a variety of fungicides used to control late blight in petri dish assays at concentrations ranging from 1 to 100 μg a.i./ml. Exposure of each of these normally heterothallic single mating type isolates of P. infestans to 9 of the 11 commercial fungicide formulations tested resulted in the formation of oospores after 2 to 4 weeks. The highest numbers of oospores were formed on media amended with Ridomil 2E (metalaxyl) and Ridomil Gold EC (mefenoxam) at 0.1 to 10 μg a.i./ml, averaging as many as 471 and 450 oospores per petri dish, respectively. Several other fungicides including Maneb, Manzate (Mancozeb), Curzate (cymoxanil + mancozeb), and Acrobat MZ (dimethomorph + mancozeb) also induced oospore formation, producing from 0 to 200 oospores per plate at fungicide concentrations from 0.1 to 10 μg a.i./ml. The metalaxyl resistant isolates formed oospores in response to the fungicides more often than the metalaxyl sensitive isolates. No oospores were formed on media amended with Bravo (chlorothalonil) or Tattoo C (chlorothalonil + propamocarb HCl) and these compounds completely suppressed growth of the isolates at 0.1 and 1 μg a.i./ml. Three metalaxyl resistant A2 isolates mated with both A1 and A2 isolates after exposure to the fungicides Ridomil 2E and Ridomil Gold EC. Alterations in mating type expression were also observed in a metalaxyl sensitive A1 isolate after exposure to Benlate (benomyl). Copious amounts of chemicals are applied annually to potato and tomato production areas to control late blight. Our results indicate that a wide range of chemically diverse fungicides can induce normally heterothallic metalaxyl resistant isolates of P. infestans to form oospores in vitro after short exposures to the fungicides.
DA - 2000/11//
PY - 2000/11//
DO - 10.1094/PHYTO.2000.90.11.1201
VL - 90
IS - 11
SP - 1201-1208
SN - 0031-949X
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033745281&partnerID=MN8TOARS
KW - fungicide resistance
KW - Irish potato famine
KW - oomycetes
KW - potato late blight
KW - Solanum tuberosum
ER -
TY - JOUR
TI - Applications of tagging and mapping insect resistance loci in plants
AU - Yencho, GC
AU - Cohen, MB
AU - Byrne, PF
T2 - ANNUAL REVIEW OF ENTOMOLOGY
AB - This review examines how molecular markers can be used to increase our understanding of the mechanisms of plant resistance to insects and develop insect resistant crops. We provide a brief description of the types of molecular markers currently being employed, and describe how they can be applied to identify and track genes of interest in a marker-assisted breeding program. A summary of the work reported in this field of study, with examples in which molecular markers have been applied to increase understanding of the mechanistic and biochemical bases of resistance in potato and maize plant/pest systems, is provided. We also describe how molecular markers can be applied to develop more durable insect-resistant crops. Finally, we identify key areas in molecular genetics that we believe will provide exciting and productive research opportunities for those working to develop insect-resistant crops.
DA - 2000///
PY - 2000///
DO - 10.1146/annurev.ento.45.1.393
VL - 45
IS - 1
SP - 393-422
SN - 1545-4487
KW - insect-resistant crops
KW - host-plant resistance
KW - plant breeding
KW - molecular markers
KW - QTL
ER -
TY - JOUR
TI - Use of matrix attachment regions (MARs) to minimize transgene silencing
AU - Allen, GC
AU - Spiker, S
AU - Thompson, WF
T2 - PLANT MOLECULAR BIOLOGY
DA - 2000/6//
PY - 2000/6//
DO - 10.1023/A:1006424621037
VL - 43
IS - 2-3
SP - 361-376
SN - 0167-4412
KW - chromatin structure
KW - gene silencing
KW - MAR
KW - nuclear matrix
KW - nuclear scaffold
KW - SAR
ER -
TY - JOUR
TI - Reproductive strategies and karyotype of the burrowing nematode, Radopholus similis
AU - Kaplan, D. T.
AU - Opperman, C. H.
T2 - Journal of Nematology
DA - 2000///
PY - 2000///
VL - 32
IS - 2
SP - 126-133
ER -
TY - JOUR
TI - Phylogenetic analysis of geographically diverse Radopholus similis via rDNA sequence reveals a monomorphic motif
AU - Kaplan, D. T.
AU - Thomas, W. K.
AU - Frisse, L. M.
AU - Sarah, J. L.
AU - Stanton, J. M.
AU - Speijer, P. R.
AU - Marin, D. H.
AU - Opperman, C. H.
T2 - Journal of Nematology
DA - 2000///
PY - 2000///
VL - 32
IS - 2
SP - 134-142
ER -
TY - PAT
TI - Method for reducing expression variability of transgenes in plant cells
AU - Thompson, W.
AU - Allen, G.
AU - Mankin, S.
C2 - 2000///
DA - 2000///
PY - 2000///
ER -
TY - JOUR
TI - Inferring linkage disequilibrium between a polymorphic marker locus and a trait locus in natural populations
AU - Luo, Z. W.
AU - Tao, S. H.
AU - Zeng, Z. B.
T2 - Genetics
DA - 2000///
PY - 2000///
VL - 156
IS - 1
SP - 457-467
ER -
TY - JOUR
TI - Geminiviruses - Models for plant DNA replication, transcription and cell cycle regulation ([correction to] vol 35, pg 105, 2000)
AU - Hanley-Bowdoin, L.
AU - Settlage, S. B.
AU - Orozco, B. M.
AU - Nagar, S.
AU - Robertson, D.
T2 - Critical Reviews in Biochemistry and Molecular Biology
DA - 2000///
PY - 2000///
VL - 35
IS - 4
SP - U4
ER -
TY - JOUR
TI - Evaluation of biological and chemical seed treatments to improve stand of snap bean across the southern United States
AU - Keinath, AP
AU - Batson, WE
AU - Caceres, J
AU - Elliott, ML
AU - Sumner, DR
AU - Brannen, PM
AU - Rothrock, CS
AU - Huber, DM
AU - Benson, DM
AU - Conway, KE
AU - Schneider, RN
AU - Motsenbocker, CE
AU - Cubeta, MA
AU - Ownley, BH
AU - Canaday, CH
AU - Adams, PD
AU - Backman, PA
AU - Fajardo, J
T2 - CROP PROTECTION
AB - Thirteen bacterial, four fungal, and four chemical fungicide seed treatments were evaluated one or more years in multiple field locations across the southern United States. Snap bean seed was treated in bulk with fungicides and most biocontrol agents, shipped to individual locations, and stored until planting or treated on site immediately before planting. Populations of biocontrol agents on seeds were assayed after seed treatment and planting. Analysis of variance of percent plant stand at 28 days after sowing revealed highly significant (P<0.01) effects of location and treatment in 1996, 1997 and 1998. A treatment by location interaction also occurred in 1996 and 1997. When treatments tested in two or three years were analyzed together, no biological seed treatments significantly affected percent stand. Carboxin significantly increased percent stand compared with nontreated seed in data sets combined from 1997 and 1998 and 1996 to 1998; captan and carboxin plus metalaxyl also increased stand in 1997 and 1998. Improvements in efficacy and consistency of biological seed treatments are necessary before they can be recommended for use in snap bean production.
DA - 2000/8//
PY - 2000/8//
DO - 10.1016/S0261-2194(00)00047-8
VL - 19
IS - 7
SP - 501-509
SN - 1873-6904
KW - biocontrol agents
KW - seed treatments
KW - fungicides
ER -
TY - JOUR
TI - Effects of ovariectomy and mating on the activity of the corpora allata in adult female Blattella germanica (L.) (Dictyoptera : Blattellidae)
AU - Holbrook, GL
AU - Bachmann, JAS
AU - Schal, C
T2 - PHYSIOLOGICAL ENTOMOLOGY
AB - Summary In adult female cockroaches, the ovary greatly affects the synthesis of Juvenile Hormone (JH) by the corpora allata, and in females of some cockroach species, removal of the ovaries results in a permanent depression of JH synthesis. We report that the corpora allata in ovariectomised, adult virgins of the German cockroach, Blattella germanica (L.), increase and then decrease in activity, as they do in intact females. Moreover, the distal tubules in the left colleterial glands of ovariectomised females accumulate abundant protein, the production of which is regulated by JH. In both ovariectomised and sham‐operated females, the activity of the corpora allata more than tripled between days 1 and 4 of adulthood, during which the oöcytes of sham‐operated females grew considerably in length. The corpora allata of sham‐operated females produced even more JH on day 7, but very little on day 10, by which time all females had oviposited. The glands of ovariectomised females, by constrast, produced a similar amount of JH on day 7 as on day 4, but much less on day 10. Beginning on day 13, the activity of the corpora allata increased again in ovariectomised females, an increase that did not occur until day 22 in sham‐operated females. Mating of ovariectomised females on day 6 resulted in a significant increase in the activity of the corpora allata by day 10. We conclude that both the ovary and mating stimulate the synthesis of JH early in the reproductive cycle, but that neither is needed for the occurrence of a complete cycle of JH synthesis.
DA - 2000/3//
PY - 2000/3//
DO - 10.1046/j.1365-3032.2000.00161.x
VL - 25
IS - 1
SP - 27-34
SN - 0307-6962
KW - Blattella germanica
KW - colleterial glands
KW - corpora allata
KW - Juvenile Hormone
KW - mating
KW - ovariectomy
KW - vitellogenesis
ER -
TY - JOUR
TI - Antisense and sense expression of a sucrose binding protein homologue gene from soybean in transgenic tobacco affects plant growth and carbohydrate partitioning in leaves
AU - Pedra, JHF
AU - Delu, N
AU - Pirovani, CP
AU - Contim, LAS
AU - Dewey, RE
AU - Otoni, WC
AU - Fontes, EPB
T2 - PLANT SCIENCE
AB - We isolated a cDNA from a soybean library, which encodes sucrose binding protein (SBP) homologue, designated S-64. To analyze the function of the SBP homologue, transgenic tobacco plants were obtained by introducing chimeric genes containing the s-64 coding region linked to the 35S CaMV promoter, either in the sense or antisense orientation, via Agrobacterium tumefaciens-mediated transformation. The accumulation of the SBP homologue was increased in transgenic plants expressing the heterologous sbp gene, whereas those expressing the antisense construct had reduced levels of the protein. The antisense transgenic plants developed symptoms characteristic of an inhibition of sucrose translocation and displayed a reduction in plant growth and development. In contrast, overexpression of the protein accelerated plant growth and the onset of flowering induction. The overall developmental performance of the transgenic plants was correlated with their photosynthetic rate under normal conditions. While photosynthesis in the antisense lines was decreased, in the sense lines photosynthetic rates were increased. Furthermore, both antisense repression and overexpression of the SBP homologue in transgenic lines altered carbohydrate partitioning in mature leaves. Taken together, these results indicate that S-64 protein is functionally analogous to SBP, representing an important component of the sucrose translocation pathway in plants.
DA - 2000/3/7/
PY - 2000/3/7/
DO - 10.1016/S0168-9452(99)00223-X
VL - 152
IS - 1
SP - 87-98
SN - 1873-2259
KW - Nicotiana
KW - soybean
KW - sucrose binding protein
KW - sucrose transport
ER -
TY - JOUR
TI - 17 beta-Estradiol and ICI-182780 regulate the hair follicle cycle in mice through an estrogen receptor-alpha pathway
AU - Chanda, S
AU - Robinette, CL
AU - Couse, JF
AU - Smart, RC
T2 - AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM
AB - Estradiol (E(2)) applied topically twice weekly to mouse skin at doses as low as 1 nmol inhibited hair growth by blocking the transition of the hair follicle from the resting phase (telogen) to the growth phase (anagen). In contrast, application of =10 nmol of other steroids produced limited inhibition. Topical treatment with the estrogen receptor (ER) antagonist ICI-182780 reversed the effects of E(2), and when applied alone, ICI-182780 caused a telogen-to-anagen transition. Both E(2) and ICI-182780 were highly effective at their site of application but not at distant sites, indicating the direct rather than secondary systemic nature of their effects. Western analysis detected a 65-kDa ER-alpha immunoreactive dermal protein, and Northern analysis revealed the presence of a 6.7-kb ER-alpha mRNA. A ribonuclease protection assay confirmed the presence of ER-alpha transcripts but failed to detect ER-beta transcripts. These findings implicate a skin-specific ER-alpha pathway in the regulation of the hair follicle cycle.
DA - 2000/2//
PY - 2000/2//
DO - 10.1152/ajpendo.2000.278.2.e202
VL - 278
IS - 2
SP - E202-E210
SN - 1522-1555
KW - skin
KW - hair growth
KW - hormones
KW - androgens
ER -
TY - JOUR
TI - Segregation of leptine glycoalkaloids and resistance to Colorado potato beetle (Leptinotarsa decemlineata (Say)) in F2 Solanum tuberosum (4x) x S-chacoense (4x) potato progenies
AU - Yencho, GC
AU - Kowalski, SP
AU - Kennedy, GG
AU - Sanford, LL
T2 - AMERICAN JOURNAL OF POTATO RESEARCH
DA - 2000///
PY - 2000///
DO - 10.1007/BF02853941
VL - 77
IS - 3
SP - 167-178
SN - 1874-9380
KW - insect resistance
KW - host plant resistance
KW - plant breeding
KW - solanine
KW - chaconine
KW - leptinine
ER -
TY - JOUR
TI - Role of feeding in the reproductive 'group effect' in females of the German cockroach Blattella germanica (L.)
AU - Holbrook, GL
AU - Armstrong, E
AU - Bachmann, JAS
AU - Deasy, BM
AU - Schal, C
T2 - JOURNAL OF INSECT PHYSIOLOGY
AB - We have found that whether a female German cockroach, Blattella germanica (L.), is kept alone or in the presence of another female has a major impact on how fast it reproduces and how much it eats. By the sixth day of adulthood, females paired since adult eclosion had substantially larger oöcytes than did females isolated during the same time, and females paired with intact females, or with ones rendered incapable of feeding, consumed more rat chow in the first six days of adulthood than did isolated females. The stimulatory effect of pairing on reproduction was, however, partially independent of feeding because the oöcytes of solitary and paired females differed in size on day 6 even when they were given, and had consumed, the same amount of food. This result was confirmed with analysis of covariance using the total food intake of a female as the covariate in the analysis. A female's social condition probably influenced the development of its oöcytes by affecting the quantity of juvenile hormone synthesized by its corpora allata. The corpora allata of paired females produced more hormone than did those of isolated ones, even when all females had consumed an equivalent amount of food. Moreover, females treated with a juvenile hormone analog, fenoxycarb, reproduced more quickly than identically reared and fed control females, showing that juvenile hormone could influence reproduction independently of feeding. We conclude that both group rearing and food intake accelerate oöcyte development by diminishing the brain's inhibition on the synthesis of juvenile hormone.
DA - 2000/6//
PY - 2000/6//
DO - 10.1016/S0022-1910(99)00201-2
VL - 46
IS - 6
SP - 941-949
SN - 1879-1611
KW - cockroach
KW - reproduction
KW - feeding
KW - group effect
KW - social facilitation
ER -
TY - JOUR
TI - Rhabdomyolysis in two foals with polysaccharide storage myopathy
AU - Byrne, E.
AU - Cohen, N.
AU - Jones, S. L.
AU - Zimmel, D. N.
AU - Valberg, S.
T2 - Compendium on Continuing Education for the Practicing Veterinarian
DA - 2000///
PY - 2000///
VL - 22
IS - 5
SP - 503
ER -
TY - JOUR
TI - Path analysis of the correlation between fruit number and plant traits of cucumber populations
AU - Cramer, CS
AU - Wehner, TC
T2 - HORTSCIENCE
AB - The relationships between fruit yield and yield components in several cucumber ( Cucumis sativus L.) populations were investigated as well as how those relationships changed with selection for improved fruit yield. In addition, the correlations between fruit yield and yield components were partitioned into partial regression coefficients (path coefficients and indirect effects). Eight genetically distinct pickling and slicing cucumber populations, differing in fruit yield and quality, were previously subjected to modified half-sib family recurrent selection. Eight families from three selection cycles (early, intermediate, late) of each population were evaluated for yield components and fruit number per plant in four replications in each of two testing methods, seasons, and years. Since no statistical test for comparing the magnitudes of two correlations was available, a correlation ( r ) of 0.7 to 1.0 or –0.7 to –1.0 ( r 2 ≥ 0.49) was considered strong, while a correlation of –0.69 to 0.69 was considered weak. The number of branches per plant had a direct positive effect on, and was correlated ( r = 0.7) with the number of total fruit per plant over all populations, cycles, seasons, years, plant densities, and replications. The number of nodes per branch, the percentage of pistillate nodes, and the percentage of fruit set were less correlated ( r < |0.7|) with total fruit number per plant (fruit yield) than the number of branches per plant. Weak correlations between yield components and fruit yield often resulted from weak correlations among yield components. The correlations among fruit number traits were generally strong and positive ( r ≥ 0.7). Recurrent selection for improved fruit number per plant maintained weak path coefficients and correlations between yield components and total fruit number per plant. Selection also maintained weak correlations among yield components. However, the correlations and path coefficients of branch number per plant on the total fruit number became more positive ( r = 0.67, 0.75, and 0.82 for early, intermediate, and late cycles, respectively) with selection. Future breeding should focus on selecting for the number of branches per plant to improve total fruit number per plant.
DA - 2000/7//
PY - 2000/7//
DO - 10.21273/hortsci.35.4.708
VL - 35
IS - 4
SP - 708-711
SN - 0018-5345
KW - cucurbitaceae
KW - Cucumis sativus
KW - earliness
KW - fruit shape
KW - indirect selection
KW - path coefficients
KW - yield components
ER -
TY - JOUR
TI - Nuclear genes resolve Mesozoic-aged divergences in the insect order Lepidoptera
AU - Wiegmann, BM
AU - Mitter, C
AU - Regier, JC
AU - Friedlander, TP
AU - Wagner, DM
AU - Nielsen, ES
T2 - MOLECULAR PHYLOGENETICS AND EVOLUTION
AB - Compared to the number of genes available for study of both younger and older divergences, few genes have yet been identified that can strongly resolve phylogenetic splits of Mesozoic age ( approximately 65-250 mya). Thus, reconstruction of Mesozoic-age phylogenies, exemplified by basal divergences within the major orders of holometabolous insects, is likely to be especially dependent on combining multiple lines of evidence. This study tests the potential of the 18S ribosomal RNA gene for reconstructing Mesozoic-aged divergences within the insect order Lepidoptera and its ability when combined with a second, previously analyzed nuclear gene (phosphoenolpyruvate carboxykinase, PEPCK) to strongly resolve these relationships. 18S sequences were obtained for 21 taxa, representing major clades of Lepidoptera plus outgroups from the other "panorpoid orders. A well-corroborated morphology-based "test phylogeny was used to evaluate the effects of partitioning the 18S gene according to variable versus conserved domains, paired versus unpaired sites in the secondary structure, and transition versus transversion substitutions. Likelihood and unweighted parsimony analyses of the 18S data recover the "test phylogeny" almost completely, with no improvement of agreement or support provided by any form of weighting or partitioning. No conflict in signal between 18S and PEPCK was detected by the partition homogeneity test. Combined parsimony analysis yielded strong bootstrap support for nearly all relationships, much higher than for either gene alone, thereby also providing strong evidence on several hypotheses about the early evolution of lepidopteran-plant interactions. These genes in combination may be widely useful for resolving insect divergences of comparable age.
DA - 2000/5//
PY - 2000/5//
DO - 10.1006/mpev.1999.0746
VL - 15
IS - 2
SP - 242-259
SN - 1095-9513
ER -
TY - JOUR
TI - Insulin-like growth factor I disparately regulates prolactin and growth hormone synthesis and secretion: Studies using the teleost pituitary model
AU - Fruchtman, S
AU - Jackson, L
AU - Borski, R
T2 - ENDOCRINOLOGY
AB - Although insulin-like growth factor I (IGF-I)’s inhibition of GH release is well documented, little is known of its control of GH synthesis at the posttranscriptional level. The manner by which IGF-I alters PRL synthesis and secretion is also unclear. This study was undertaken to examine the role IGF-I plays in regulating in vitro PRL and GH synthesis and release using the teleost pituitary model system. This model allows for isolation of nearly homogenous populations of distinct pituitary cell types that can be cultured in a completely defined, hormone-free medium. Tissues containing PRL cells and those consisting of GH cells were dissected from pituitaries of hybrid striped bass and exposed to varying concentrations of IGF-I, IGF-II, and insulin for 18–20 h. Exposure to graded doses of IGF-I markedly stimulated fractional, total, and newly synthesized PRL release in a dose-dependent fashion (ED50 for fractional release, 35 ng/ml or 4.6 nm; P < 0.0001). IGF-II and insulin also increased PRL release, but only at 10-fold higher concentrations than the lowest effective IGF-I dose. The total PRL content in the incubations and PRL synthesis, as measured by [35S]methionine incorporation, were not altered by IGF-I. By contrast, IGF-I potently reduced GH release (ED50, 29 ng/ml or 3.8 nm; P < 0.0001) and synthesis. Both 100 and 1000 ng/ml IGF-I decreased newly synthesized GH and total GH content (P < 0.001). Insulin and IGF-II mimicked IGF’s action in attenuating GH release, but only at 10- to 11-fold higher concentrations. Taken together, these findings clearly indicate that IGF-I disparately regulates PRL and GH synthesis and secretion. We show that the effects of IGF-I on pituitary hormone release occur in a variety of species, suggesting that its actions are well conserved. The inhibition of GH release and synthesis by IGF-I probably reflects a negative feedback loop for maintaining tight control over GH cell function. These findings further indicate that IGF-I is a potent and specific secretagogue of PRL release in vertebrates.
DA - 2000/8//
PY - 2000/8//
DO - 10.1210/en.141.8.2886
VL - 141
IS - 8
SP - 2886-2894
SN - 1945-7170
ER -
TY - JOUR
TI - Hypothalamic arginine vasotocin mRNA abundance variation across sexes and with sex change in a coral reef fish
AU - Godwin, J
AU - Sawby, R
AU - Warner, RR
AU - Crews, D
AU - Grober, MS
T2 - BRAIN BEHAVIOR AND EVOLUTION
AB - Gonadal hormones are important mediators of sexual and aggressive behavior in vertebrates. Recent evidence suggests that the peptide hormones arginine vasotocin (AVT) and its mammalian homologue arginine vasopressin (AVP) often critically mediate these gonadal hormone effects on behavior and have direct influences on behavioral variation. Behavioral differences between sexes, across reproductive states, and even among closely related species are correlated with differences in central AVT/AVP systems in many species. We report differences in hypothalamic AVT mRNA levels between distinct alternate male phenotypes and with female-to-male sex change in the bluehead wrasse (Thalassoma bifasciatum), a teleost fish. The aggressively dominant and strongly courting male phenotype has greater numbers of AVT mRNA producing cells in the magnocellular preoptic area of the hypothalamus than females. Levels of AVT mRNA within these cells in dominant males are also approximately three times female levels whereas the non-aggressive male phenotype has AVT mRNA levels approximately twice female levels. Behavioral sex change is very rapid in this species and is not dependent on the presence of gonads. Conversely, rapid increases in sexual and aggressive behavior during sex change are closely paralleled by approximate fourfold increases in hypothalamic AVT-mRNA levels. The behavioral plasticity shown by bluehead wrasses in response to social environment might be mediated in part by a neuropeptide, AVT, with changes in the gonads and gonadal hormones as the result rather than the cause of behavioral dominance.
DA - 2000/2//
PY - 2000/2//
DO - 10.1159/000006643
VL - 55
IS - 2
SP - 77-84
SN - 1421-9743
KW - vasotocin
KW - mRNA
KW - preoptic area
KW - sex differences
KW - sex change
KW - teleost
ER -
TY - JOUR
TI - Genetic, biochemical, and behavioral uniformity among populations of Myzus nicotianae and Myzus persicae
AU - Clements, KM
AU - Sorenson, CE
AU - Wiegmann, BM
AU - Neese, PA
AU - Roe, RM
T2 - ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA
AB - Abstract Prior to designation as distinct species, an appellation presently in question, the tobacco aphid, Myzus nicotianae Blackman (Homoptera: Aphididae), was classified as a tobacco‐feeding form of the green peach aphid, Myzus persicae (Sulzer). In this study, RAPD polymorphisms distinguished members of the Myzus persicae complex ( M. persicae and M. nicotianae ) from three outgroup Myzus species ( M. cerasi (F.), M. hemerocallis Takahashi, and M. varians Davidson). Polymorphisms within the complex did not separate populations on the basis of host association (tobacco versus other host plants) or geographic origin (collections from the United States, Europe, and Japan). Similarly, while GC‐MS analysis of cuticular hydrocarbon profiles revealed both developmental and inter‐populational differences within the M. persicae complex, it did not separate populations of tobacco feeding aphids from those collected off non‐tobacco hosts. Finally, with the exception of their responses to a choice between lettuce and collards, the host preference behavior of a green peach aphid population, a red tobacco aphid population, and a green tobacco aphid population was indistinguishable in host preference experiments. These results add to a growing body of evidence suggesting M. nicotianae and M. persicae are conspecific.
DA - 2000/6//
PY - 2000/6//
DO - 10.1046/j.1570-7458.2000.00666.x
VL - 95
IS - 3
SP - 269-281
SN - 1570-7458
KW - green peach aphid
KW - cuticular hydrocarbons
KW - Myzus nicotianae
KW - Myzus persicae
KW - RAPD-PCR
KW - tobacco
KW - tobacco aphid
KW - Homoptera
KW - Aphididae
ER -
TY - JOUR
TI - Forced convection in a Couette flow in a composite duct: An analysis of thermal dispersion and non-Darcian effects
AU - Xiong, M.
AU - Kuznetsov, A. V.
T2 - Journal of Porous Media
DA - 2000///
PY - 2000///
DO - 10.1615/jpormedia.v3.i3.60
VL - 3
IS - 3
SP - 245-255
ER -
TY - JOUR
TI - Development and evaluation of a standard method for screening for resistance to Radopholus similis in bananas
AU - Marin, DH
AU - Barker, KR
AU - Kaplan, DT
AU - Sutton, TB
AU - Opperman, CH
T2 - PLANT DISEASE
AB - The description and evaluation of a standard assay method for screening for resistance of bananas to the burrowing nematode (Radopholus similis) under greenhouse conditions is presented. Seven banana genotypes, ranging from susceptible to resistant, were used to evaluate the method. Banana plants from tissue culture, grown in 0.4-liter Styrofoam cups containing sterilized sand as substrate, were maintained in the greenhouse for 4 weeks before inoculation. Two hundred burrowing nematodes, reared in monoxenic carrot-disk culture, were used as inoculum for each container. Plants were kept in the greenhouse for an additional 8 weeks at about 27°C and 80% relative humidity after inoculation. Burrowing nematodes reproduced well in the susceptible cultivars False Horn, Grande Naine, Valery, and Lacatan, whereas the reproductive fitness was very low in the resistant cultivars Pisang Jari Buaya and Yangambi. An intermediate reaction between these two groups was observed with Pisang mas. A similar trend was obtained in a follow-up field test, which indicated that the method is accurate and reliable. Assessments of total-root necrosis associated with this pathogen were also comparable between greenhouse and field conditions. However, nematode effects on the roots were more severe in the greenhouse test than in the field. In spite of low nematode reproductive fitness, root necrosis was relatively high in the two resistant cultivars tested in the greenhouse trial.
DA - 2000/6//
PY - 2000/6//
DO - 10.1094/pdis.2000.84.6.689
VL - 84
IS - 6
SP - 689-693
SN - 0191-2917
KW - Cavendish
KW - Musa AAA
KW - nematode resistance
ER -
TY - JOUR
TI - Characterization of devH, a gene encoding a putative DNA binding protein required for heterocyst function in Anabaena sp strain PCC 7120
AU - Hebbar, PB
AU - Curtis, SE
T2 - JOURNAL OF BACTERIOLOGY
AB - ABSTRACT The devH gene was identified in a screen for Anabaena sp. strain PCC 7120 sequences whose transcripts increase in abundance during a heterocyst development time course. The product of devH contains a helix-turn-helix motif similar to the DNA binding domain of members of the cyclic AMP receptor protein family, and the protein is most closely related to the cyanobacterial transcriptional activator NtcA. devH transcripts are barely detectable in vegetative cells and are induced approximately fivefold after nitrogen starvation. This induction is absent in the two developmental mutants hetR and ntcA . The gene is expressed as monocistronic transcripts with multiple 5′ termini, and the ∼500-bp region 5′ to devH was shown to have promoter activity in vivo. The devH gene was insertionally inactivated by the integration of plasmid sequences within the open reading frame. Nitrogen starvation of the devH mutant induces heterocysts of wild-type morphology, but the mutant is inviable in the absence of fixed nitrogen and unable to reduce acetylene aerobically.
DA - 2000/6//
PY - 2000/6//
DO - 10.1128/jb.182.12.3572-3581.2000
VL - 182
IS - 12
SP - 3572-3581
SN - 1098-5530
ER -
TY - JOUR
TI - Analysis of intraspecies polymorphism in the ribosomal DNA cluster of the cockroach Blattella germanica
AU - Mukha, DV
AU - Sidorenko, AP
AU - Lazebnaya, , IV
AU - Wiegmann, BM
AU - Schal, C
T2 - INSECT MOLECULAR BIOLOGY
AB - HindIII restriction digests of the rDNA repeat unit of the German cockroach, Blattella germanica, reveal significant intraspecies sequence polymorphism. This variability is probably caused by structural differences within the nontranscribed spacer regions (NTS) of the ribosomal repeat unit. HindIII rDNA fragment polymorphisms in three cockroach strains show that individuals from different populations may have different HindIII rDNA patterns, whereas individuals within populations exhibit relatively similar rDNA patterns. We suggest that HindIII restriction fragment polymorphisms within cockroach ribosomal DNA will be a valuable tool for measuring population-level parameters within and between natural cockroach populations.
DA - 2000/4//
PY - 2000/4//
DO - 10.1046/j.1365-2583.2000.00175.x
VL - 9
IS - 2
SP - 217-222
SN - 0962-1075
KW - Blattella
KW - ribosomal DNA structure
KW - polymorphism
ER -
TY - JOUR
TI - An integrated genetic map of Populus deltoides based on amplified fragment length polymorphisms
AU - Wu, RL
AU - Han, YF
AU - Hu, JJ
AU - Fang, JJ
AU - Li, L
AU - Li, ML
AU - Zeng, ZB
T2 - THEORETICAL AND APPLIED GENETICS
DA - 2000/6//
PY - 2000/6//
DO - 10.1007/s001220051431
VL - 100
IS - 8
SP - 1249-1256
SN - 0040-5752
KW - AFLP
KW - heteroduplex
KW - intercross marker
KW - linkage map
KW - Populus deltoides
KW - testcross marker
ER -
TY - JOUR
TI - Varying migration and deme size and the feasibility of the shifting balance
AU - Peck, SL
AU - Ellner, SP
AU - Gould, F
T2 - EVOLUTION
AB - EvolutionVolume 54, Issue 1 p. 324-327 Free Access VARYING MIGRATION AND DEME SIZE AND THE FEASIBILITY OF THE SHIFTING BALANCE Steven L. Peck, Steven L. Peck USDA/ARS, Tropical Fruit and Vegetable Research Laboratory, P.O. Box 4459, Hilo, Hawaii 96720 E-mail: sp@aloha.net Present address: Zoology Department, Brigham Young University, Provo, Utah 84602–5255; E-mail: steven_peck@byu.edu.Search for more papers by this authorStephen P. Ellner, Stephen P. Ellner Biomathematics Graduate Program, Department of Statistics, North Carolina State University, Raleigh, North Carolina 27695–8203 E-mail: ellner@stat.ncsu.eduSearch for more papers by this authorFred Gould, Fred Gould Department of Entomology, North Carolina State University, Raleigh, North Carolina 27695–7634 E-mail: fgould@unity.ncsu.eduSearch for more papers by this author Steven L. Peck, Steven L. Peck USDA/ARS, Tropical Fruit and Vegetable Research Laboratory, P.O. Box 4459, Hilo, Hawaii 96720 E-mail: sp@aloha.net Present address: Zoology Department, Brigham Young University, Provo, Utah 84602–5255; E-mail: steven_peck@byu.edu.Search for more papers by this authorStephen P. Ellner, Stephen P. Ellner Biomathematics Graduate Program, Department of Statistics, North Carolina State University, Raleigh, North Carolina 27695–8203 E-mail: ellner@stat.ncsu.eduSearch for more papers by this authorFred Gould, Fred Gould Department of Entomology, North Carolina State University, Raleigh, North Carolina 27695–7634 E-mail: fgould@unity.ncsu.eduSearch for more papers by this author First published: 09 May 2007 https://doi.org/10.1111/j.0014-3820.2000.tb00035.xCitations: 17 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume54, Issue1February 2000Pages 324-327 ReferencesRelatedInformation
DA - 2000/2//
PY - 2000/2//
DO - 10.1111/j.0014-3820.2000.tb00035.x
VL - 54
IS - 1
SP - 324-327
SN - 0014-3820
KW - pesticide resistance
KW - shifting balance theory
KW - stepping stone model
KW - stochastic migration
KW - varying deme size
ER -
TY - JOUR
TI - Stringent control of transgene expression in Arabidopsis thaliana using the Top10 promoter system
AU - Love, J
AU - Scott, AC
AU - Thompson, WF
T2 - PLANT JOURNAL
AB - Summary We show that the tightly regulated tetracycline‐sensitive Top10 promoter system (Weinmann et al . Plant J. 1994, 5, 559–569) is functional in Arabidopsis thaliana . A pure breeding A. thaliana line (JL‐tTA/8) was generated which expressed a chimeric fusion of the tetracycline repressor and the activation domain of Herpes simplex virus (tTA), from a single transgenic locus. Plants from this line were crossed with transgenics carrying the ER‐targeted green fluorescent protein coding sequence ( mGFP 5 ) under control of the Top10 promoter sequence. Progeny from this cross displayed ER‐targeted GFP fluorescence throughout the plant, indicating that the tTA–Top10 promoter interaction was functional in A. thaliana . GFP expression was repressed by 100 ng ml −1 tetracycline, an order of magnitude lower than the concentration used previously to repress expression in Nicotiana tabacum . Moreover, the level of GFP expression was controlled by varying the concentration of tetracycline in the medium, allowing a titred regulation of transgenic activity that was previously unavailable in A. thaliana . The kinetics of GFP activity were determined following de‐repression of the Top10::mGFP 5 transgene, with a visible ER‐targeted GFP signal appearing from 24 to 48 h after de‐repression.
DA - 2000/3//
PY - 2000/3//
DO - 10.1046/j.1365-313x.2000.00706.x
VL - 21
IS - 6
SP - 579-588
SN - 0960-7412
ER -
TY - CHAP
TI - Rhizoctonia
AU - Cubeta, M. A.
AU - Vilgalys, R.
T2 - Encyclopedia of microbiology (2nd ed.)
CN - QR9 .E53 2000
PY - 2000///
VL - 4
SP - 109-116
PB - San Diego, Calif.: Academic Press
ER -
TY - JOUR
TI - Premature termination codons destabilize ferredoxin-1 mRNA when ferredoxin-1 is translated
AU - Petracek, ME
AU - Nuygen, T
AU - Thompson, WF
AU - Dickey, LF
T2 - PLANT JOURNAL
AB - Summary Ferredoxin‐1 ( Fed‐1 ) mRNA is poorly translated in dark‐treated tobacco ( Nicotiana tabacum ) leaves, resulting in destabilization of Fed‐1 mRNA and a differential light/dark accumulation of the mRNA. Insertion of nonsense codons within the Fed‐1 coding sequence disrupts the light regulation of Fed‐1 mRNA abundance. Here we show that the nonsense codon effect results primarily from lowering the Fed‐1 mRNA stability in light‐treated leaf tissue and in rapidly growing tobacco cell cultures, but not in dark‐treated leaf tissue. These results suggest that nonsense codons trigger a decay pathway distinct from that seen for Fed‐1 mRNA in the dark. We propose that nonsense‐mediated decay of nonsense‐containing Fed‐1 mRNA occurs in light‐treated leaves and in non‐photosynthetic tobacco culture cells where Fed‐1 mRNA is being actively translated.
DA - 2000/3//
PY - 2000/3//
DO - 10.1046/j.1365-313x.2000.00705.x
VL - 21
IS - 6
SP - 563-569
SN - 1365-313X
ER -
TY - JOUR
TI - Genotype-environment interaction for quantitative trait loci affecting life span in Drosophila melanogaster
AU - Vieira, C.
AU - Pasyukova, E. G.
AU - Zeng, Z. B.
AU - Hackett, J. B.
AU - Lyman, R. F.
AU - Mackay, T. F. C.
T2 - Genetics
DA - 2000///
PY - 2000///
VL - 154
IS - 1
SP - 213-227
ER -
TY - JOUR
TI - Genetic architecture of a morphological shape difference between two Drosophila species
AU - Zeng, Z. B.
AU - Liu, J. J.
AU - Stam, L. F.
AU - Kao, C. H.
AU - Mercer, J. M.
AU - Laurie, C. C.
T2 - Genetics
DA - 2000///
PY - 2000///
VL - 154
IS - 1
SP - 299-310
ER -
TY - JOUR
TI - The multifunctional character of a geminivirus replication protein is reflected by its complex oligomerization properties
AU - Orozco, BM
AU - Kong, LJ
AU - Batts, LA
AU - Elledge, S
AU - Hanley-Bowdoin, L
T2 - JOURNAL OF BIOLOGICAL CHEMISTRY
AB - Tomato golden mosaic virus (TGMV), a member of the geminivirus family, encodes one essential replication protein, AL1, and recruits the rest of the DNA replication apparatus from its plant host. TGMV AL1 is an oligomeric protein that binds double-stranded DNA and catalyzes cleavage and ligation of single-stranded DNA. The oligomerization domain, which is required for DNA binding, maps to a region that displays strong sequence and structural homology to other geminivirus Rep proteins. To assess the importance of conserved residues, we generated a series of site-directed mutations and analyzed their impact on AL1 function in vitro and in vivo. Two-hybrid experiments revealed that mutation of amino acids 157–159 inhibited AL1-AL1 interactions, whereas mutations at nearby residues reduced complex stability. Changes at positions 157–159 also disrupted interaction between the full-length mutant protein and a glutathione S-transferase-AL1 oligomerization domain fusion in insect cells. The mutations had no detectable effect on oligomerization when both proteins contained full-length AL1 sequences, indicating that AL1 complexes can be stabilized by amino acids outside of the oligomerization domain. Nearly all of the oligomerization domain mutants were inhibited or severely attenuated in their ability to support AL1-directed viral DNA replication. In contrast, the same mutants were enhanced for AL1-mediated transcriptional repression. The replication-defective AL1 mutants also interfered with replication of a TGMV A DNA encoding wild type AL1. Full-length mutant AL1 was more effective in the interference assays than truncated proteins containing the oligomerization domain. Together, these results suggested that different AL1 complexes mediate viral replication and transcriptional regulation and that replication interference involves multiple domains of the AL1 protein. Tomato golden mosaic virus (TGMV), a member of the geminivirus family, encodes one essential replication protein, AL1, and recruits the rest of the DNA replication apparatus from its plant host. TGMV AL1 is an oligomeric protein that binds double-stranded DNA and catalyzes cleavage and ligation of single-stranded DNA. The oligomerization domain, which is required for DNA binding, maps to a region that displays strong sequence and structural homology to other geminivirus Rep proteins. To assess the importance of conserved residues, we generated a series of site-directed mutations and analyzed their impact on AL1 function in vitro and in vivo. Two-hybrid experiments revealed that mutation of amino acids 157–159 inhibited AL1-AL1 interactions, whereas mutations at nearby residues reduced complex stability. Changes at positions 157–159 also disrupted interaction between the full-length mutant protein and a glutathione S-transferase-AL1 oligomerization domain fusion in insect cells. The mutations had no detectable effect on oligomerization when both proteins contained full-length AL1 sequences, indicating that AL1 complexes can be stabilized by amino acids outside of the oligomerization domain. Nearly all of the oligomerization domain mutants were inhibited or severely attenuated in their ability to support AL1-directed viral DNA replication. In contrast, the same mutants were enhanced for AL1-mediated transcriptional repression. The replication-defective AL1 mutants also interfered with replication of a TGMV A DNA encoding wild type AL1. Full-length mutant AL1 was more effective in the interference assays than truncated proteins containing the oligomerization domain. Together, these results suggested that different AL1 complexes mediate viral replication and transcriptional regulation and that replication interference involves multiple domains of the AL1 protein. tomato golden mosaic virus activation domain glutathioneS-transferase maize streak virus Geminiviruses are a large family of plant viruses with circular, single-stranded DNA genomes that replicate in the nuclei of infected cells (reviewed in Ref. 1.Hanley-Bowdoin L. Settlage S.B. Orozco B.M. Nagar S. Robertson D. CRC Crit. Rev. Plant Sci. 1999; 18: 71-106Crossref Google Scholar). The single-stranded genome is converted to a double-stranded DNA that serves as the template for rolling circle replication (2.Saunders K. Lucy A. Stanley J. Nucleic Acids Res. 1991; 19: 2325-2330Crossref PubMed Scopus (167) Google Scholar, 3.Stenger D.C. Revington G.N. Stevenson M.C. Bisaro D.M. Proc. Natl. Acad. Sci. U. S. A. 1991; 88: 8029-8033Crossref PubMed Scopus (288) Google Scholar, 4.Heyraud F. Matzeit V. Kammann M. Schaefer S. Schell J. Gronenborn B. EMBO J. 1993; 12: 4445-4452Crossref PubMed Scopus (88) Google Scholar) and transcription (5.Sunter G. Gardiner W.E. Bisaro D.M. Virology. 1989; 170: 243-250Crossref PubMed Scopus (53) Google Scholar, 6.Sunter G. Bisaro D.M. Virology. 1989; 173: 647-655Crossref PubMed Scopus (47) Google Scholar). Geminiviruses do not encode their own polymerases and, instead, rely on host enzymes for viral DNA and RNA synthesis. These characteristics make geminiviruses excellent model systems for studying plant DNA replication and transcription mechanisms. The geminivirus, tomato golden mosaic virus (TGMV),1 has a bipartite genome that encodes seven open reading frames that are divergently transcribed. The 5′-intergenic region separating the transcription units is nearly identical between the two DNA components and includes the plus strand origin of replication (7.Lazarowitz S.G. Wu L.C. Rogers S.G. Elmer J.S. Plant Cell. 1992; 4: 799-809Crossref PubMed Scopus (116) Google Scholar, 8.Orozco B.M. Gladfelter H.J. Settlage S.B. Eagle P.A. Gentry R. Hanley-Bowdoin L. Virology. 1998; 242: 346-356Crossref PubMed Scopus (68) Google Scholar). The promoter for complementary sense transcription overlaps the replication origin (5.Sunter G. Gardiner W.E. Bisaro D.M. Virology. 1989; 170: 243-250Crossref PubMed Scopus (53) Google Scholar,9.Hanley-Bowdoin L. Elmer J.S. Rogers S.G. Plant Cell. 1989; 1: 1057-1067PubMed Google Scholar) and shares some of the cis-elements involved in origin function (10.Eagle P.A. Orozco B.M. Hanley-Bowdoin L. Plant Cell. 1994; 6: 1157-1170PubMed Google Scholar). A directly repeated sequence, GGTAG, is required for origin recognition (11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar) and transcriptional repression of the complementary sense (AL1) promoter (10.Eagle P.A. Orozco B.M. Hanley-Bowdoin L. Plant Cell. 1994; 6: 1157-1170PubMed Google Scholar). Similarly, the TATA-box and G-box transcription factor binding sites in the AL1 promoter act as replication enhancer elements (12.Eagle P.A. Hanley-Bowdoin L. J. Virol. 1997; 71: 6947-6955Crossref PubMed Google Scholar). In contrast, three elements in the TGMV intergenic region are necessary for origin function but have little or no effect on AL1 promoter activity. A hairpin structure with a 9-base pair loop sequence that is conserved among all geminiviruses is essential for replication and contains the cleavage site for initiating plus strand DNA synthesis (4.Heyraud F. Matzeit V. Kammann M. Schaefer S. Schell J. Gronenborn B. EMBO J. 1993; 12: 4445-4452Crossref PubMed Scopus (88) Google Scholar, 13.Laufs J. Traut W. Heyraud F. Matzeit V. Rogers S.G. Schell J. Gronenborn B. Proc. Natl. Acad. Sci. U. S. A. 1995; 92: 3879-3883Crossref PubMed Scopus (259) Google Scholar, 14.Orozco B.M. Hanley-Bowdoin L. J. Virol. 1996; 270: 148-158Crossref Google Scholar). A conserved sequence between the AL1 binding site and the hairpin, the AG-motif, is also required for replication (8.Orozco B.M. Gladfelter H.J. Settlage S.B. Eagle P.A. Gentry R. Hanley-Bowdoin L. Virology. 1998; 242: 346-356Crossref PubMed Scopus (68) Google Scholar). The third element, the CA motif, is located outside of the minimal origin but its deletion reduced replication 20-fold (8.Orozco B.M. Gladfelter H.J. Settlage S.B. Eagle P.A. Gentry R. Hanley-Bowdoin L. Virology. 1998; 242: 346-356Crossref PubMed Scopus (68) Google Scholar). The role of the AG- and CA-motifs in TGMV origins is not known, but one possibility is that they bind host factors that facilitate initiation of plus strand DNA replication. TGMV encodes two proteins, AL1 and AL3, that are required for efficient viral replication. AL1 is necessary for replication, whereas AL3 enhances viral DNA accumulation by an unknown mechanism (15.Elmer J.S. Brand L. Sunter G. Gardiner W.E. Bisaro D.M. Rogers S.G. Nucleic Acids Res. 1988; 16: 7043-7060Crossref PubMed Scopus (212) Google Scholar, 16.Sunter G. Hartitz M.D. Hormuzdi S.G. Brough C.L. Bisaro D.M. Virology. 1990; 179: 69-77Crossref PubMed Scopus (167) Google Scholar) (AL1 homologues are also designated C1 or Rep.) AL1 is a multifunctional protein that mediates both virus-specific recognition of its cognate origin (17.Fontes E.P.B. Gladfelter H.J. Schaffer R.L. Petty I.T.D. Hanley-Bowdoin L. Plant Cell. 1994; 6: 405-416Crossref PubMed Scopus (171) Google Scholar) and transcriptional repression by binding to the directly repeated sequence in the intergenic region (10.Eagle P.A. Orozco B.M. Hanley-Bowdoin L. Plant Cell. 1994; 6: 1157-1170PubMed Google Scholar, 12.Eagle P.A. Hanley-Bowdoin L. J. Virol. 1997; 71: 6947-6955Crossref PubMed Google Scholar). AL1 initiates and terminates plus strand replication (13.Laufs J. Traut W. Heyraud F. Matzeit V. Rogers S.G. Schell J. Gronenborn B. Proc. Natl. Acad. Sci. U. S. A. 1995; 92: 3879-3883Crossref PubMed Scopus (259) Google Scholar, 14.Orozco B.M. Hanley-Bowdoin L. J. Virol. 1996; 270: 148-158Crossref Google Scholar, 18.Heyraud-Nitschke F. Schumacher S. Laufs J. Schaefer S. Schell J. Gronenborn B. Nucleic Acids Res. 1995; 23: 910-916Crossref PubMed Scopus (142) Google Scholar) and induces the accumulation of a host replication factor, proliferating cell nuclear antigen, in infected cells (19.Nagar S. Pedersen T.J. Carrick K. Hanley-Bowdoin L. Robertson D. Plant Cell. 1995; 7: 705-719Crossref PubMed Scopus (156) Google Scholar). Recombinant AL1 specifically binds double-stranded DNA (11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar, 20.Fontes E.P.B. Luckow V.A. Hanley-Bowdoin L. Plant Cell. 1992; 4: 597-608Crossref PubMed Scopus (136) Google Scholar), cleaves and ligates single-stranded DNA in the invariant sequence of the hairpin loop (14.Orozco B.M. Hanley-Bowdoin L. J. Virol. 1996; 270: 148-158Crossref Google Scholar, 21.Laufs J. Schumacher S. Geisler N. Jupin I. Gronenborn B. FEBS Lett. 1995; 377: 258-262Crossref PubMed Scopus (67) Google Scholar), and hydrolyzes ATP (22.Desbiez C. David C. Mettouchi A. Laufs J. Gronenborn B. Proc. Natl. Acad. Sci. U. S. A. 1995; 92: 5640-5644Crossref PubMed Scopus (106) Google Scholar, 23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar). TGMV AL1 also interacts with itself (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar), the viral replication enhancer protein AL3 (24.Settlage S.B. Miller B. Hanley-Bowdoin L. J. Virol. 1996; 70: 6790-6795Crossref PubMed Google Scholar), and a maize homologue of the cell cycle regulatory protein, retinoblastoma (25.Ach R.A. Durfee T. Miller A.B. Taranto P. Hanley-Bowdoin L. Zambriski P.C. Gruissem W. Mol. Cell. Biol. 1997; 17: 5077-5086Crossref PubMed Scopus (202) Google Scholar). We previously mapped the TGMV AL1 domains for double-stranded DNA binding, single-stranded DNA cleavage and ligation, and AL1 oligomerization (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar, 26.Orozco B.M. Hanley-Bowdoin L. J. Biol. Chem. 1998; 273: 24448-24456Abstract Full Text Full Text PDF PubMed Scopus (81) Google Scholar). The DNA cleavage/ligation domain was located to the first 120 amino acids, and the oligomerization domain was mapped between amino acids 120 and 181. DNA binding activity required amino acids 1–130 for protein-DNA contacts and the AL1 oligomerization domain. Because of its importance in AL1 function, we have further characterized the sequences required for oligomerization in vitro and assessed the impact of site-directed mutations in the domain in vivo. Constructs are listed in Table I. The plasmid pNSB148, which contains the AL1 coding sequence in a pUC118-background, was used as the template for site-directed mutagenesis (27.Kunkel T.A. Proc. Natl. Acad. Sci. U. S. A. 1985; 82: 482-492Google Scholar). The oligonucleotide primers and resulting clones are also listed in TableI. DNA fragments containing the mutations were verified by DNA sequence analysis. Plant expression cassettes for mutant AL1 proteins were generated by subcloningSalI/NcoI fragments (TGMV A position 2442 and 2059) from the mutant clones into the same sites in the wild type AL1 plant expression cassette pMON1549 (11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar). In pMON1549, AL1 expression is under the control of the cauliflower mosaic virus 35S promoter with a duplicated enhancer region and the pea E9 rbcS 3′-end.Table IAL1 mutationsMutationOligonucleotideBaculovirus vectorYeast GAL4-ADPlant expressionWild typeN/ApMON1680pNSB809pMON1549FQ118CACTTCGACCGTCGACCGCGGCTTCTCCCCAN/ApNSB872pNSB866D120CACTTCGGCCGGCGACCGCGGCTTCTCCCCAN/ApNSB871pNSB865RS-R125GCAACCTCCTgcAGCggccgcACCGTCGACCTGGAN/ApNSB786pNSB695QT130CAGCGTCGTTgctaGcTgcGCAACCTCCTCTAGCAN/ApNSB788pNSB696ND133CTGCTGCAGCGgCcgcAGATGTTTGGCAApNSB603PNSB790pNSB670E–N140GGAAGAAGCAgcTAACGCggCcGCTGCAGCGTCGTpNSB604PNSB893pNSB640KEE146TCTGCAGGGCTgCggCcgcGGAAGAAGCATTTAApNSB605PNSB894pNSB641REK154TTCTGGGATTgcggCcgcAATTATCTGCAGGGpNSB606pNSB759pNSB671EKY159GAACTGAAATAAAgcggccgCTGGGATTTTCTCTCpNSB607pNSB760pNSB672Q-HN165GCTATTTAGAgcGgcGAACgcAAATAAATATTTTTCTGGGATpNSB608pNSB761pNSB698N-DR172ATCAAATATCgcAgCTAgcgcGCTATTTAGATTGTGpNSB609pNSB762pNSB707K–E179GAAGCCATGGcgCcGGAGTCgcATCAAATATCCpNSB610pNSB763pNSB697 Open table in a new tab Baculovirus vectors were generated for expression of mutant and truncated AL1 proteins in insect cells. Expression vectors coding for mutant AL1 proteins were made by subcloningBglII/BamHI inserts from the mutant plant expression cassettes into the BamHI site of pMON27025 (28.Luckow V.A. Lee S.C. Barry G.F. Olins P.O. J. Virol. 1993; 67: 4566-4579Crossref PubMed Google Scholar). Expression vectors for the truncated proteins, AL1119–352(pNSB516), AL11–120 (pNSB388), and AL11–180(pNSB517), have been described previously (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar). The N-terminal truncations, AL1134–352 and AL1147–352, were generated by inserting a double-stranded oligonucleotide containing anSphI site into the NotI site of pNSB593 and pNSB595 to create in-frame start codons. AL1160–352 was created by inserting an SphI linker with a start codon (New England Biolabs, Beverly, MA) into the SspI site of pMON1539 (29.Hanley-Bowdoin L. Elmer J.S. Rogers S.G. Proc. Natl. Acad. Sci. U. S. A. 1990; 87: 1446-1450Crossref PubMed Scopus (84) Google Scholar). SphI/BamHI fragments from the resulting clones were inserted into the same sites of the baculovirus vector, pNSB448 (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar), to give pNSB803 (AL1134–352), pNSB876 (AL1147–352), and pNSB633 (AL1160–352). The C-terminal truncation, AL11–158 (pNSB646), was generated by digesting pMON1539 with NdeI and SspI, repairing with Klenow, and subcloning into the filled BamHI site of pMON27025 to create an in-frame stop codon. The AL11–168 truncation, pNSB708, was created by inserting anXbaI linker into the repaired BssHII of pNSB609, generating an in-frame stop codon. Yeast expression cassettes were generated using the pAS1–1 and pACT2 vectors from CLONTECH (Palo Alto, CA). TheBamHI/NdeI fragment of pMON1539 was cloned into the same sites of pAS2–1 to give pNSB736, which contained the GAL4 DNA binding domain fused to wild type AL1 sequences. The ends of the sameBamHI/NdeI fragment were repaired with Klenow and cloned into the SmaI site of pACT2 to give pNSB735. TheAatII/BamHI fragment of pNSB735 was then replaced with the AatII/BamHI fragment from pMON1549. The resulting clone, pNSB809, contained the GAL4 activation domain (AD) fused to wild type AL1 sequences. Mutant AL1 yeast expression cassettes were created by replacing the wild typeAatII/BamHI fragment of pNSB735 with mutantAatII/BamHI fragments from the corresponding plant expression cassettes. Protoplasts were isolated from Nicotiana tabacum (BY-2) orNicoxiana benthamiana suspension cells, electroporated, and cultured according to published methods (11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar). For replication assays, N. tabacum transfections included 15 μg each of replicon DNA containing a partial tandem copy of TGMV B (pTG1.4B, Ref. 17.Fontes E.P.B. Gladfelter H.J. Schaffer R.L. Petty I.T.D. Hanley-Bowdoin L. Plant Cell. 1994; 6: 405-416Crossref PubMed Scopus (171) Google Scholar), wild type or mutant AL1 plant expression cassette, and an AL3 plant expression cassette (pNSB46, Ref. 11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar). For the interference assays, 2 μg of replicon DNA containing a partial tandem copy of TGMV A (pMON1565, Ref. 14.Orozco B.M. Hanley-Bowdoin L. J. Virol. 1996; 270: 148-158Crossref Google Scholar) was cotransfected with 40 μg of mutant AL1 expression cassette or the empty expression vector (pMON921, Ref. 11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar). Total DNA was extracted 3 days post-transfection and analyzed for double- and single-stranded viral DNA accumulation by DNA gel blot hybridization (11.Fontes E.P.B. Eagle P.A. Sipe P.A. Luckow V.A. Hanley-Bowdoin L. J. Biol. Chem. 1994; 269: 8459-8465Abstract Full Text PDF PubMed Google Scholar). The viral DNA was quantified by phosphorimager analysis in a minimum of three independent experiments. For transcriptional repression assays, N. benthamianaprotoplasts were transfected with 15 μg of luc reporter construct (pNSB114), 15 μg of AL1 expression cassette, and 36 μg of sheared salmon sperm DNA (10.Eagle P.A. Orozco B.M. Hanley-Bowdoin L. Plant Cell. 1994; 6: 1157-1170PubMed Google Scholar). Luciferase activity in total soluble protein extracts was measured 36 h post-transfection and standardized for protein concentration. Repression was determined as the ratio of Luc activity in the absence versus the presence of AL1. Each expression cassette was assayed in triplicate in at least three independent experiments. Recombinant proteins were produced inSpodoptera frugiperda Sf9 cells using a baculovirus expression system according to published protocols (14.Orozco B.M. Hanley-Bowdoin L. J. Virol. 1996; 270: 148-158Crossref Google Scholar, 24.Settlage S.B. Miller B. Hanley-Bowdoin L. J. Virol. 1996; 70: 6790-6795Crossref PubMed Google Scholar). Protein extracts from cells co-expressing authentic and GST-AL1 fusion proteins were assayed for AL1 oligomerization by co-purification on glutathione-Sepharose (24.Settlage S.B. Miller B. Hanley-Bowdoin L. J. Virol. 1996; 70: 6790-6795Crossref PubMed Google Scholar). Co-purification was monitored by SDS-polyacrylamide electrophoresis followed by transfer to nitrocellulose membrane (Schleicher and Schuell) and immunoblotting using the ECL detection system (Amersham Pharmacia Biotech). Primary antibodies were rabbit polyclonal anti-GST (Upstate Biotechnology Inc.) and anti-AL1 antisera (24.Settlage S.B. Miller B. Hanley-Bowdoin L. J. Virol. 1996; 70: 6790-6795Crossref PubMed Google Scholar). The Saccharomyces cerevisiae strain Y187 (MATα,ura3–52, his3–200, ade 2–101,trp 1–901, leu 2–3, 112,gal4Δ, met −, gal80Δ,URA3::GAL1 UAS-GAL1 TATA-lacZ) was transformed using lithium acetate/polyethylene glycol (30.Geitz D. St. Jean A. Woods R.A. Schiesti R.H. Nucleic Acids Res. 1992; 20: 1425Crossref PubMed Scopus (2895) Google Scholar). The DNAs were pNSB736, which expresses the GAL4 binding domain-wild type AL1 fusion, and either pNSB809, which produces the GAL4 AD-wild type AL1 protein, or the equivalent cassettes corresponding to the GAL4 AD-AL1 mutants. For β-galactosidase assays, yeast transformants were grown to an A 600 of 0.5 in 3 ml of synthetic dropout medium lacking tryptophan and leucine (31.Sherman F. Fink G.R. Hicks J.B. Laboratory Course Manual for Methods in Yeast Genetics. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY1986Google Scholar). Yeast were pelleted at 1000 × g for 5 min, rinsed with Z buffer (0.1m NaPO4, pH 7, 10 mm KCl, 1 mm MgSO4, 40 mmβ-mercaptoethanol) (31.Sherman F. Fink G.R. Hicks J.B. Laboratory Course Manual for Methods in Yeast Genetics. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY1986Google Scholar), and resuspended in 300 μl of Z buffer. The cells were subjected to three freeze/thaw cycles in liquid nitrogen and centrifuged at 5000 × g for 2 min. The supernatant (150 μl) was assayed for β-galactosidase activity in a total reaction volume of 250 μl using the substrateo-nitrophenyl β-d-galactopyranoside, as described by CLONTECH. Accumulation of theo-nitrophenol product was measured atA 420 using a BioKinetics microplate reader (Bio-Tek Instrument Inc., Winooski, VT). Protein concentrations were measured by Bradford assays (Bio-Rad). The enzyme-specific activity (1 unit = 1.0 μm product/min at pH7.3 at 37 °C) resulting from interaction between two-hybrid cassettes carrying wild type AL1 sequences was determined using purified β-galactosidase (Sigma) as the standard. The relative activities of the mutants were normalized against the wild type AL1 interaction level, which was set to 100%. The β-galactosidase specific activity for wild type and mutant AL1 proteins was adjusted for background from pNSB736 alone. The different constructs were tested in a minimum of two experiments, each of which assayed four independent transformants for each construct. For immunoblot analysis, individual yeast transformants were grown in 5 ml of medium containing 1% yeast extract, 2% bacto-peptone, 2% glucose, pH 5.8 (31.Sherman F. Fink G.R. Hicks J.B. Laboratory Course Manual for Methods in Yeast Genetics. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY1986Google Scholar) to an A 600 of 1. An equal volume of crushed ice was added and the culture was centrifuged at 1000 × g for 5 min. The resulting pellet was washed once with ice cold water and resuspended in 80 μl of modified radioimmune precipitation buffer (150 mm NaCl, 1% (v/v) Nonidet P-40, 0.5% (w/v) sodium deoxycholate, 50 mmTris-HCl, pH 7.5 (32.Harlow E. Lane D. Antibodies, A Laboratory Manual. Cold Spring Harbor Press, Cold Spring Harbor, NY1988Google Scholar), containing 1% (w/v) SDS) and protease inhibitors (6 μg/ml pepstatin A, 10 μg/ml leupeptin, 20 μg/ml aprotinin, 8 mm benzamidine, 1 mmphenylmethylsulfonyl fluoride). Glass beads (40 μl, 425–600 μm, Sigma) were added and the sample was vortexed at maximum speed for four 30-s intervals separated by 2-min intervals on ice. The sample was then centrifuged at 5000 × g for 2 min at 4 °C. The supernatant was recovered, and the protein concentration was determined using Bradford assays. Total protein (100 μg) was resolved on 12% polyacrylamide/SDS gels and analyzed by immunoblotting using a GAL4 AD monoclonal antibody at 0.4 μg/ml (CLONTECH). The domains for TGMV AL1 DNA binding and DNA cleavage/ligation activities are well defined, and key structural and sequence motifs have been identified for these functions (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar, 26.Orozco B.M. Hanley-Bowdoin L. J. Biol. Chem. 1998; 273: 24448-24456Abstract Full Text Full Text PDF PubMed Scopus (81) Google Scholar), whereas the AL1 oligomerization domain has only been broadly located to the center of the protein (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar). In this paper, closely spaced N- and C-terminal truncations were generated to define the limits of the AL1 oligomerization domain (Fig.1 A). A GST fusion corresponding to full-length AL1 (GST-AL1) was co-expressed with the truncated AL1 proteins in baculovirus-infected insect cells, and protein complexes were purified on glutathione-Sepharose resin. Total extracts and purified proteins were resolved by SDS-polyacrylamide gel electrophoresis, and proteins were visualized by immunoblotting with AL1 and GST polyclonal antisera. As reported previously (23.Orozco B.M. Miller A.B. Settlage S.B. Hanley-Bowdoin L. J. Biol. Chem. 1997; 272: 9840-9846Abstract Full Text Full Text PDF PubMed Scopus (98) Google Scholar), the C-terminal truncation AL11–180 (Fig. 1 B,lanes 3 and 6) copurified with full-length GST-AL1. Further deletion of the C terminus to amino acid 168 (lanes 2 and 5) or 158 (lanes 1 and4) abolished interactions with GST-AL1, demonstrating that the C-terminal limit of the oligomerization domain is between position 168 and 180. The N-terminal truncations to amino acids 134 (Fig.1 C, lanes 3 and 6), 147 (lanes 2 and 5), and 160 (lanes 1 and 4) showed a gradual disappearance of interaction with GST-AL1. AL1134–352 consistently displayed interactions with GST-AL1, whereas AL1147–352 and AL1160–352interactions varied between weak to background levels, making it more difficult to define the N-terminal limit. Contacts outside the oligomerization domain may contribute to complex stability or multimerization and account for the low level interactions observed with AL1147–352 and AL1160–352. To address this possibility, we asked whether full-length AL1 copurified when only the oligomerization domain was fused to GST (GST-AL1119–180). Full-length AL1 interacted with GST-AL1119–180 but not with GST alone (Fig.2 B, lanes 1 and2), demonstrating that amino acids 119–180 are sufficient for oligomerization. We then examined the abilities of the N-terminal AL1 truncations to bind GST-AL1119–180. In this assay, deletion to positions 119 (Fig. 1 D, lanes 1 and5) and 134 (lanes 2 and 6) did not affect oligomerization, whereas further deletion to positions 147 (lanes 3 and 7) and 160 (lanes 4 and8) abolished interactions with GST-AL1119–180. Together, these results showed that AL1 amino acids 134–180 contain the oligomerization domain and that sequences outside the domain contribute stabilizing contacts. Alanine substitutions were generated in conserved charged or hydrophobic residues within the oligomerization domain to identify key amino acids that contribute to AL1 interactions (Fig.3, the mutations are designated by the corresponding wild type sequence and the position of the last amino acid that was altered; dashes indicate amino acids that were not changed). Alanine was selected because it is structurally neutral and should not interfere with normal protein folding. The mutations are within a region that includes a pair of predicted α-helices (26.Orozco B.M. Hanley-Bowdoin L. J. Biol. Chem. 1998; 273: 24448-24456Abstract Full Text Full Text PDF PubMed Scopus (81) Google Scholar) and downstream sequences required for oligomerization. All of the mutant AL1 proteins co-purified with GST-AL1 on glutathione resin when co-expressed in insect cells (Fig. 2 A), showing that they formed stable complexes with the wild type protein. Similar results were observed when both the test and GST fusion proteins carried the mutations (data not shown). In contrast, when interactions between the mutant AL1 proteins and GST-AL1119–180 were examined mutant EKY159 (Fig. 2 B, lane 6) was defective for AL1 interactions. Thus, sequences outside of the oligomerization domain in the full-length AL1 masked the effect of the EKY159 mutation in Fig.2 A, which is consistent with our previous conclusion that sequences outside the oligomerization domain stabilize AL1 interactions. The oligomerization mutant, EKY159, was assayed with truncated GST-AL1 proteins to locate the stabilizing region. As shown above, EKY159 bound full-length GST-AL1 (Fig. 2 C,lanes 1 and 5) but not GST-AL1119–180 (lanes 4 and 8). EKY159 also bound an N-terminal truncation, GST-AL1119–352(lanes 3 and 7), whereas no interaction was detected with a C-terminal truncation, GST-AL11–180(lanes 2 and 6), demonstrating that the AL1 C terminus contributes stabilizing contacts. The quantitative impact of each mutation on AL1 oligomerization was measured using a yeast two-hybrid system. Expression cassettes for wild type or mutant AL1 fused to the GAL4 AD were cotransformed into yeast with a cassette for wild type AL1 fused to the GAL4 DNA binding domain. Activation of a GAL4-responsive promoter driving a lacZreporter was assayed by measuring β-galactosidase activity in total soluble protein extracts. In extracts from yeast cotransfected with AD and binding domain cassettes carrying wild type AL1 sequences, 142 mu/mg total protei
DA - 2000/3/3/
PY - 2000/3/3/
DO - 10.1074/jbc.275.9.6114
VL - 275
IS - 9
SP - 6114-6122
SN - 0021-9258
ER -
TY - JOUR
TI - Temporal dynamics of Phytophthora blight on bell pepper in relation to the mechanisms of dispersal of primary inoculum of Phytophthora capsici in soil
AU - Sujkowski, LS
AU - Parra, GR
AU - Gumpertz, ML
AU - Ristaino, JB
T2 - PHYTOPATHOLOGY
AB - The effect of components of primary inoculum dispersal in soil on the temporal dynamics of Phytophthora blight epidemics in bell pepper was evaluated in field and growth-chamber experiments. Phytophthora capsici may potentially be dispersed by one of several mechanisms in the soil, including inoculum movement to roots, root growth to inoculum, and root-to-root spread. Individual components of primary inoculum dispersal were manipulated in field plots by introducing (i) sporangia and mycelia directly in soil so that all three mechanisms of dispersal were possible, (ii) a plant with sporulating lesions on the soil surface in a plastic polyvinyl chloride (PVC) tube so inoculum movement to roots was possible, (iii) a wax-encased peat pot containing sporangia and mycelia in soil so root growth to inoculum was possible, (iv) a wax-encased peat pot containing infected roots in soil so root-to-root spread was possible, (v) noninfested V8 vermiculite media into soil directly as a control, or (vi) wax-encased noninfested soil as a control. In 1995 and 1996, final incidence of disease was highest in plots where sporangia and mycelia were buried directly in soil and all mechanisms of dispersal were operative (60 and 32%) and where infected plants were placed in PVC tubes on the soil surface and inoculum movement to roots occurred with rainfall (89 and 23%). Disease onset was delayed in 1995 and 1996, and final incidence was lower in plants in plots where wax-encased sporangia (6 and 22%) or wax-encased infected roots (22%) were buried in soil and root growth to inoculum or root-to-root spread occurred. Incidence of root infections was higher over time in plots where inoculum moved to roots or all mechanisms of dispersal were possible. In growth-chamber studies, ultimately all plants became diseased regardless of the dispersal mechanism of primary inoculum, but disease onset was delayed when plant roots had to grow through a wax layer to inoculum or infected roots in tension funnels that contained small volumes of soil. Our data from both field and growth-chamber studies demonstrate that the mechanism of dispersal of the primary inoculum in soil can have large effects on the temporal dynamics of disease.
DA - 2000/2//
PY - 2000/2//
DO - 10.1094/phyto.2000.90.2.148
VL - 90
IS - 2
SP - 148-156
SN - 0031-949X
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0033958523&partnerID=MN8TOARS
KW - root disease
KW - spatial dynamics
ER -
TY - JOUR
TI - Lignin structure in a mutant pine deficient in cinnamyl alcohol dehydrogenase
AU - Lapierre, C
AU - Pollet, B
AU - MacKay, JJ
AU - Sederoff, RR
T2 - JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
AB - Cinnamyl alcohol dehydrogenase (CAD) activity is deficient in loblolly pine (Pinus taeda L.) harboring a mutated allele of the cad gene (cad-n1). We compared lignin structure of CAD-deficient and wild-type pines, both types segregating within full-sib families obtained by controlled crosses. The type and frequency of lignin building units and distribution of interunit bonds were determined from the GC-MS analysis of thioacidolysis monomers and dimers. While the lignin content was only slightly reduced, the lignin structure was dramatically modified by the mutation in both mature and juvenile trees. Lignins from CAD-deficient pine displayed unusually high levels of coniferaldehyde and dihydroconiferyl alcohol. In addition, biphenyl and biphenyl ether bonds were in large excess in these abnormal lignins. These results suggest that the CAD-deficient pines efficiently compensate for the shortage in normal lignin precursors by utilizing nontraditional wall phenolics to construct unusual lignins particularly enriched in resistant interunit bonds.
DA - 2000/6//
PY - 2000/6//
DO - 10.1021/jf991398p
VL - 48
IS - 6
SP - 2326-2331
SN - 0021-8561
KW - lignification
KW - altered lignin structure
KW - pine (Pinus taeda L.)
KW - thioacidolysis
KW - dihydroconiferyl alcohol
ER -
TY - JOUR
TI - Evaluation of wounds as a factor to infection of cabbage by ascospores of Sclerotinia sclerotiorum
AU - Hudyncia, J
AU - Shew, HD
AU - Cody, BR
AU - Cubeta, MA
T2 - PLANT DISEASE
AB - A semi-selective medium was used to examine the aerobiology of ascospores of Sclerotinia sclerotiorum in five commercial cabbage fields in eastern North Carolina. Ascospores were present in all five fields from 26 September to 30 November. However, numbers of ascospores varied greatly depending on location, sampling date, and time. In general, peak ascospore deposition occurred between 11:00 A.M. and 1:00 P.M., with the number of colonies recovered ranging from 3 to 55/dish (9 cm in diameter). Peak ascospore numbers at all locations were found from mid- to late October, but a second, smaller peak was also evident at each location in late November. Information obtained was employed to evaluate the role of wounding in infection of cabbage by ascospores of S. sclerotiorum in controlled environmental chambers. A method for production and release of ascospores of S. sclerotiorum was employed in controlled-environment chambers for the inoculation of cabbage plants with one of three representative foliar wounds: a bruise, a cut, or a non-lethal freeze. Wounding treatments were applied to 7-week-old cabbage plants, misting was added to maintain continuous leaf wetness, and ascospores were released from apothecia twice daily for four consecutive days. Spore trapping with a semi-selective medium indicated that inoculum was evenly distributed within the chambers and deposition was similar to levels recorded in the field. At 31 days after inoculation, disease incidence ranged from 0% on the control to 96% on the freeze treatments. Freeze-treated plants showed the highest disease severity throughout the entire incubation period. Mean area under the disease progress curve of severity values were 0, 0.2, 34 and 60 for the control, cut, bruise, and freeze treatments, respectively. Results indicate that freeze and bruise injuries are important factors associated with infection of cabbage by S. sclerotiorum.
DA - 2000/3//
PY - 2000/3//
DO - 10.1094/PDIS.2000.84.3.316
VL - 84
IS - 3
SP - 316-320
SN - 0191-2917
ER -
TY - CHAP
TI - Molecular dissection of quantitative traits: new perspectives from populus
AU - Wu, R.
AU - Li, B.
AU - Zeng, Z.-B.
T2 - Molecular biology of woody plants
A2 - Jain, S. M.
A2 - Minocha, S. C.
CN - SD403.5 .M66 2000
PY - 2000///
VL - 1
SP - 475-490
PB - Dordrecht; Boston: Kluwer Academic
ER -
TY - JOUR
TI - Impact of forest genetics on sustainable forestry: results from two cycles of loblolly pine breeding in the U.S.
AU - Li, B.
AU - McKeand, Steven
AU - Weir, R.
T2 - Journal of Sustainable Forestry
DA - 2000///
PY - 2000///
DO - 10.1300/j091v10n01_09
VL - 10
IS - 1/2
SP - 79–85
ER -
TY - JOUR
TI - Characterization of Lyme disease spirochetes isolated from ticks and vertebrates in North Carolina
AU - Ryan, , JR
AU - Apperson, CS
AU - Orndorff, PE
AU - Levine, JF
T2 - JOURNAL OF WILDLIFE DISEASES
AB - Borrelia burgdorferi isolates obtained from numerous locations and from different hosts in North Carolina, were compared to previously characterized strains of the Lyme disease spirochete and other Borrelia spp. The spirochete isolates were confirmed to be B. burgdorferi sensu stricto based on immunofluorescence (IFA) using a monoclonal antibody to outer surface protein A (Osp A [H5332]) and polymerase chain reaction (PCR) using a species-specific nested primer for a conserved region of the gene that encodes for flagellin. In addition, the isolates tested positive in Western blots with species-specific monoclonal antibodies for outer surface protein A and OspB (84c), and the genus-specific, monoclonal antibody to flagellin (H9724). Infectivity studies with several of these isolates were conducted using Mus musculus and Oryzomys palustris and the isolates exhibited markedly different levels of infectivity. This study demonstrates that B. burgdorferi sensu stricto is present and naturally transmitted on the Outer Banks and in the Coastal Plain and Piedmont regions of North Carolina.
DA - 2000/1//
PY - 2000/1//
DO - 10.7589/0090-3558-36.1.48
VL - 36
IS - 1
SP - 48-55
SN - 1943-3700
KW - Borrelia burgdorferi
KW - isolate characterization
KW - Lyme disease
KW - ticks
KW - vertebrates
ER -
TY - JOUR
TI - The case for molecular mapping in forest tree breeding
AU - Rongling, W.
AU - Zeng, Z.-B.
AU - McKeand,
AU - O'Malley, D. M.
T2 - Plant Breeding Reviews
DA - 2000///
PY - 2000///
VL - 19
IS - 2000
SP - 41-68
ER -
TY - JOUR
TI - Taste sensitivity of insect herbivores to deterrents is greater in specialists than in generalists: A behavioral test of the hypothesis with two closely related caterpillars
AU - Bernays, EA
AU - Oppenheim, S
AU - Chapman, RF
AU - Kwon, H
AU - Gould, F
T2 - JOURNAL OF CHEMICAL ECOLOGY
DA - 2000/2//
PY - 2000/2//
DO - 10.1023/A:1005430010314
VL - 26
IS - 2
SP - 547-563
SN - 1573-1561
KW - Heliothis virescens
KW - Heliothis subflexa
KW - caterpillar
KW - diet breadth
KW - deterrent compound
KW - feeding behavior
KW - postingestive toxicity
KW - plant secondary metabolite
ER -
TY - JOUR
TI - Phylogeny of the treehoppers (Insecta : Hemiptera : Membracidae): Evidence from two nuclear genes
AU - Cryan, , JR
AU - Wiegmann, BM
AU - Deitz, LL
AU - Dietrich, CH
T2 - MOLECULAR PHYLOGENETICS AND EVOLUTION
AB - We present a molecular systematic investigation of relationships among family-group taxa of Membracidae, comprising nearly 3.5 kb of nucleotide sequence data from the nuclear genes elongation factor-1alpha (EF-1alpha: 958 bp) and 28S ribosomal DNA (28S rDNA: 2363 bp); data partitions are analyzed separately and in combination for 79 taxa. Analysis of the combined sequence data provided a better-resolved and more robust hypothesis of membracid phylogeny than did separate analyses of the individual genes. Results support the monophyly of the family Membracidae and indicate the presence of two major lineages (Centrotinae + Stegaspidinae + Centrodontinae and Darninae + Membracinae + Smiliinae). Within Membracidae, molecular data support the following assertions: (1) the previously unplaced genera Antillotolania and Deiroderes form a monophyletic group with Microcentrini; (2) Centrodontini and Nessorhinini are monophyletic clades that arise independently from within the Centrotinae; (3) Centrotinae is paraphyletic with respect to Centrodontinae; (4) the subfamily Membracinae is monophyletic and possibly allied with the darnine tribe Cymbomorphini; (5) the subfamily Darninae is paraphyletic; (6) the subfamily Smiliinae is paraphyletic, with molecular evidence indicating the exclusion of Micrutalini and perhaps Acutalini and Ceresini; and (7) Membracidae arose and diversified in the New World with multiple subsequent colonizations of the Old World. Our phylogenetic results suggest that morphology-based classifications of the Membracidae need to be reevaluated in light of emerging molecular evidence.
DA - 2000/11//
PY - 2000/11//
DO - 10.1006/mpev.2000.0832
VL - 17
IS - 2
SP - 317-334
SN - 1055-7903
KW - Membracoidea
KW - Membracidae
KW - treehoppers
KW - molecular phylogenetics
KW - elongation factor-1 alpha
KW - 28S ribosomal DNA
KW - combined data analysis
KW - biogeography
ER -
TY - JOUR
TI - Ocular lesions associated with systemic hypertension in cats: 69 cases (1985-1998)
AU - Maggio, F
AU - DeFrancesco, TC
AU - Atkins, CE
AU - Pizzirani, S
AU - Gilger, BC
AU - Davidson, MG
T2 - JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION
AB - Abstract Objective —To characterize clinical and clinicopathologic findings, response to treatment, and causes of systemic hypertension in cats with hypertensive retinopathy. Design —Retrospective study. Animals —69 cats with hypertensive retinopathy. Procedure —Medical records from cats with systemic hypertension and hypertensive retinopathy were reviewed. Results —Most cats (68.1%) were referred because of vision loss; retinal detachment, hemorrhage, edema, and degeneration were common findings. Cardiac abnormalities were detected in 37 cats, and neurologic signs were detected in 20 cats. Hypertension was diagnosed concurrently with chronic renal failure (n = 22), hyperthyroidism (5), diabetes mellitus (2), and hyperaldosteronism (1). A clearly identifiable cause for hypertension was not detected in 38 cats; 26 of these cats had mild azotemia, and 12 did not have renal abnormalities. Amlodipine decreased blood pressure in 31 of 32 cats and improved ocular signs in 18 of 26 cats. Conclusions and Clinical Relevance —Retinal lesions, caused predominantly by choroidal injury, are common in cats with hypertension. Primary hypertension in cats may be more common than currently recognized. Hypertension should be considered in older cats with acute onset of blindness; retinal edema, hemorrhage, or detachment; cardiac disease; or neurologic abnormalities. Cats with hypertensioninduced ocular disease should be evaluated for renal failure, hyperthyroidism, diabetes mellitus, and cardiac abnormalities. Blood pressure measurements and funduscopic evaluations should be performed routinely in cats at risk for hypertension (preexisting renal disease, hyperthyroidism, and age > 10 years). Amlodipine is an effective antihypertensive agent in cats.( J Am Vet Med Assoc 2000;217:695–702)
DA - 2000/9/1/
PY - 2000/9/1/
DO - 10.2460/javma.2000.217.695
VL - 217
IS - 5
SP - 695-702
SN - 0003-1488
ER -
TY - JOUR
TI - Nongenomic membrane actions of glucocorticoids in vertebrates
AU - Borski, RJ
T2 - TRENDS IN ENDOCRINOLOGY AND METABOLISM
AB - For decades, it was widely assumed that glucocorticoids (GCs) work solely through changes in gene expression to exert their physiological actions, a process that normally takes several hours to occur. However, recent evidence indicates that GCs might also act at the membrane through specific receptors to exert multiple rapid effects on various tissues and cells. GCs modulate hormone secretion, neuronal excitability, behavior, cell morphology, carbohydrate metabolism and other processes within seconds or minutes. These early actions occur independent of the genome and are transduced by the same biochemical effector pathways responsible for mediating rapid responses to neurotransmitters. The biological significance of most rapid GC effects are not well understood, but many might be related to the important functions that this hormone plays in modulating stress responses.
DA - 2000/12//
PY - 2000/12//
DO - 10.1016/S1043-2760(00)00325-8
VL - 11
IS - 10
SP - 427-436
SN - 1043-2760
ER -
TY - JOUR
TI - Models of protein sequence evolution and their applications
AU - Thorne, JL
T2 - CURRENT OPINION IN GENETICS & DEVELOPMENT
AB - Homologous sequences are correlated due to their common ancestry. Probabilistic models of sequence evolution are employed routinely to properly account for these phylogenetic correlations. These increasingly realistic models provide a basis for studying evolution and for exploiting it to better understand protein structure and function. Notable recent advances have been made in the treatment of insertion and deletion events, the estimation of amino-acid replacement rates, and the detection of positive selection.
DA - 2000/12//
PY - 2000/12//
DO - 10.1016/S0959-437X(00)00142-8
VL - 10
IS - 6
SP - 602-605
SN - 1879-0380
ER -
TY - JOUR
TI - Effects of heterogeneity in forced convection in a porous medium: parallel plate channel or circular duct
AU - Nield, DA
AU - Kuznetsov, AV
T2 - INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
AB - The effects of variation (in the transverse direction) of permeability and thermal conductivity, on fully developed forced convection in a parallel plate channel or circular duct filled with a saturated porous medium, is investigated analytically on the basis of a Darcy or Dupuit–Forchheimer model. It is shown that the Dupuit–Forchheimer problem reduces to the Darcy problem with a changed permeability variation. The cases of isoflux and isothermal boundaries are treated in turn. The bulk of the results pertain to a two-step variation, but the case of a weak continuous variation is also considered. The results for the parallel plate geometry and for the circular duct geometry are qualitatively similar. The replacement of isoflux boundaries by isothermal boundaries leads to a reduction of Nusselt number but otherwise there is little change in the pattern. The results demonstrate that the effect of permeability variation is that an above average permeability near the walls leads to an increase in Nusselt number, and this is explained in terms of variation in the curvature of the temperature profile. The effect of conductivity variation is more complex; there are two opposing effects and the Nusselt number is not always a monotonic function of the conductivity variation.
DA - 2000/11//
PY - 2000/11//
DO - 10.1016/S0017-9310(00)00025-9
VL - 43
IS - 22
SP - 4119-4134
SN - 1879-2189
ER -
TY - JOUR
TI - Diversity and contribution of the intestinal bacterial community to the development of Musca domestica (Diptera : Muscidae) larvae
AU - Zurek, L
AU - Schal, C
AU - Watson, DW
T2 - JOURNAL OF MEDICAL ENTOMOLOGY
AB - The bacterial diversity in the intestinal tract of Musca domestica L. was examined in larvae collected from turkey bedding and corn silage. Aerobic culturing yielded 25 bacterial species, including 11 from larvae collected from turkey bedding and 14 from larvae collected from corn silage. Providencia rettgeri (Hadley, Elkins & Caldwell) was the only species common to both environments. Two mammalian pathogens, Yersinia pseudotuberculosis (Pfeiffer) and Ochrobactrum anthropi (Holmes), were isolated from the larval intestinal tracts. The majority of isolates represented facultatively anaerobic heterotrophs capable of fermentation. The significance of these bacteria for development of house fly larvae was evaluated by bioassays on trypticase soy egg yolk agar. Pure cultures of individual bacterial species isolated from the intestinal tract of larvae from turkey bedding supported development of flies to a much greater extent than those isolated from larvae from corn silage. House fly development was best supported by a Streptococcus sanguis (White) isolate. The significance of bacteria for development of house flies is discussed.
DA - 2000/11//
PY - 2000/11//
DO - 10.1603/0022-2585-37.6.924
VL - 37
IS - 6
SP - 924-928
SN - 0022-2585
KW - house fly
KW - intestinal tract
KW - bacteria
KW - artificial medium
KW - larval development
ER -
TY - PCOMM
TI - Untitled
AU - Atkins, C. E.
AU - DeFrancesco, T.
DA - 2000///
PY - 2000///
SP - 471
ER -
TY - JOUR
TI - Site-directed mutagenesis of the magB gene affects growth and development in Magnaporthe grisea
AU - Fang, EGC
AU - Dean, RA
T2 - MOLECULAR PLANT-MICROBE INTERACTIONS
AB - G protein signaling is commonly involved in regulating growth and differentiation of eukaryotic cells. We previously identified MAGB, encoding a Galpha subunit, from Magnaporthe grisea, and disruption of MAGB led to defects in a number of cellular responses, including appressorium formation, conidiation, sexual development, mycelial growth, and surface sensing. In this study, site-directed mutagenesis was used to further dissect the pleiotropic effects controlled by MAGB. Conversion of glycine 42 to arginine was predicted to abolish GTPase activity, which in turn would constitutively activate G protein signaling in magB(G42R). This dominant mutation caused autolysis of aged colonies, misscheduled melanization, reduction in both sexual and asexual reproduction, and reduced virulence. Furthermore, magB(G42R) mutants were able to produce appressoria on both hydrophobic and hydrophilic surfaces, although development on the hydrophilic surface was delayed. A second dominant mutation, magB(G203R) (glycine 203 converted to arginine), was expected to block dissociation of the Gbetagamma from the Galpha subunit, thus producing a constitutively inactive G protein complex. This mutation did not cause drastic phenotypic changes in the wild-type genetic background, other than increased sensitivity to repression of conidiation by osmotic stress. However, magB(G203R) is able to complement phenotypic defects in magB mutants. Comparative analyses of the phenotypical effects of different magB mutations are consistent with the involvement of the Gbetagamma subunit in the signaling pathways regulating cellular development in M. grisea.
DA - 2000/11//
PY - 2000/11//
DO - 10.1094/MPMI.2000.13.11.1214
VL - 13
IS - 11
SP - 1214-1227
SN - 0894-0282
KW - rice blast
KW - signal transduction
ER -
TY - JOUR
TI - Screening the cucumber germplasm collection for fruit storage ability
AU - Wehner, T. C.
AU - Shetty, N. V.
AU - Wilson, L. G.
T2 - HortScience
DA - 2000///
PY - 2000///
VL - 35
IS - 4
SP - 699-707
ER -
TY - JOUR
TI - Screening the cucumber germplasm collection for combining ability for yield
AU - Wehner, T. C.
AU - Shetty, N. V.
AU - Clark, R. L.
T2 - HortScience
DA - 2000///
PY - 2000///
VL - 35
IS - 6
SP - 1141-1150
ER -
TY - JOUR
TI - Induction of growth hormone (GH) mRNA by pulsatile GH-releasing hormone in rats is pattern specific
AU - Borski, RJ
AU - Tsai, W
AU - Demott-Friberg, R
AU - Barkan, AL
T2 - AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM
AB - Growth hormone-releasing hormone (GHRH) is a main inducer of growth hormone (GH) pulses in most species studied to date. There is no information regarding the pattern of GHRH secretion as a regulator of GH gene expression. We investigated the roles of the parameters of exogenous GHRH administration (frequency, amplitude, and total amount) upon induction of pituitary GH mRNA, GH content, and somatic growth in the female rat. Continuous GHRH infusions were ineffective in altering GH mRNA levels, GH stores, or weight gain. Changing GHRH pulse amplitude between 4, 8, and 16 microg/kg at a constant frequency (Q3.0 h) was only moderately effective in augmenting GH mRNA levels, whereas the 8 microg/kg and 16 microg/kg dosages stimulated weight gain by as much as 60%. When given at a 1.5-h frequency, GHRH doubled the amount of GH mRNA, elevated pituitary GH stores, and stimulated body weight gain. In the rat model, pulsatile but not continuous GHRH administration is effective in inducing pituitary GH mRNA and GH content as well as somatic growth. These studies suggest that the greater growth rate, pituitary mRNA levels, and GH stores seen in male compared with female rats are likely mediated, in part, by the endogenous episodic GHRH secretory pattern present in males.
DA - 2000/5//
PY - 2000/5//
DO - 10.1152/ajpendo.2000.278.5.e885
VL - 278
IS - 5
SP - E885-E891
SN - 0193-1849
KW - pituitary
KW - growth
KW - pulsatility
KW - sexual dimorphism
ER -
TY - JOUR
TI - Frequency of Alleles Conferring Resistance to a Bacillus thuringiensis Toxin in a Philippine Population of Scirpophaga incertulas (Lepidoptera: Pyralidae)
AU - Bentur, J. S.
AU - Andow, D. A.
AU - Cohen, M. B.
AU - Romena, A. M.
AU - Gould, F.
T2 - Journal of Economic Entomology
AB - Journal Article Frequency of Alleles Conferring Resistance to a Bacillus thuringiensis Toxin in a Philippine Population of Scirpophaga incertulas (Lepidoptera: Pyralidae) Get access J. S. Bentur, J. S. Bentur 1 2 1Entomology and Plant Pathology Division, International Rice Research Institute, MCPO Box 3127, Makati City 1271, Philippines. Search for other works by this author on: Oxford Academic PubMed Google Scholar D. A. Andow, D. A. Andow 3 3Department of Entomology, 219 Hodson Hall, University of Minnesota, St. Paul, MN 55108. Search for other works by this author on: Oxford Academic PubMed Google Scholar M. B. Cohen, M. B. Cohen 1 1Entomology and Plant Pathology Division, International Rice Research Institute, MCPO Box 3127, Makati City 1271, Philippines. Search for other works by this author on: Oxford Academic PubMed Google Scholar A. M. Romena, A. M. Romena 1 1Entomology and Plant Pathology Division, International Rice Research Institute, MCPO Box 3127, Makati City 1271, Philippines. Search for other works by this author on: Oxford Academic PubMed Google Scholar F. Gould F. Gould 4 4Department of Entomology, North Carolina State University, Raleigh, NC 27695. Search for other works by this author on: Oxford Academic PubMed Google Scholar Journal of Economic Entomology, Volume 93, Issue 5, 1 October 2000, Pages 1515–1521, https://doi.org/10.1603/0022-0493-93.5.1515 Published: 01 October 2000
DA - 2000/10/1/
PY - 2000/10/1/
DO - 10.1603/0022-0493-93.5.1515
VL - 93
IS - 5
SP - 1515-1521
J2 - ec
LA - en
OP -
SN - 0022-0493 0022-0493
UR - http://dx.doi.org/10.1603/0022-0493-93.5.1515
DB - Crossref
KW - Bacillus thuringiensis
KW - Scirpophaga incertulas
KW - F-2 screen
KW - Bt rice
KW - Bt resistance
ER -
TY - JOUR
TI - Examining rates and patterns of nucleotide substitution in plants
AU - Muse, SV
T2 - PLANT MOLECULAR BIOLOGY
DA - 2000/1//
PY - 2000/1//
DO - 10.1023/A:1006319803002
VL - 42
IS - 1
SP - 25-43
SN - 1573-5028
KW - chloroplast genes
KW - maximum likelihood
KW - molecular clocks
KW - nucleotide substitution models
KW - rates of molecular evolution
ER -
TY - JOUR
TI - Alan Francis Bird: 1928-99
AU - Bird, D. M.
T2 - Journal of Nematology
DA - 2000///
PY - 2000///
VL - 32
IS - 1
SP - 1-3
ER -