TY - BOOK TI - Introduction to Biochemical Toxicology DA - 2001/// PY - 2001/// ET - 3rd PB - J. Wiley and Sons ER - TY - JOUR TI - Method of treating alopecia AU - Smart, R. C. AU - Oh, H.-S. DA - 2001/// PY - 2001/// VL - 6,204,258 IS - 2001 Mar. 20 ER - TY - BOOK TI - Introduction to Biochemical Toxicology A3 - Hodgson, E. A3 - Smart, R.C. DA - 2001/// PY - 2001/// ET - 3rd PB - J. Wiley and Sons ER - TY - CHAP TI - Carcinogenesis AU - Smart, R.C. AU - Akunda, J.K. T2 - Introduction to Biochemical Toxicology A2 - Hodgson, E. A2 - Smart, R.C. PY - 2001/// ET - 3rd SP - 343–398 PB - J. Wiley and Sons ER - TY - CHAP TI - Molecular Techniques in Toxicology AU - Smart, R.C. T2 - Introduction to Biochemical Toxicology A2 - Hodgson, E. A2 - Smart, R.C. PY - 2001/// ET - 3rd SP - 11–32 PB - J. Wiley and Sons ER - TY - CHAP TI - Biochemical Toxicology: Definition and Scope AU - Hodgson, E. AU - Smart, R.C. T2 - Introduction to Biochemical Toxicology A2 - Hodgson, E. A2 - Smart, R.C. PY - 2001/// SP - 1–10 PB - J. Wiley and Sons ER - TY - CONF TI - Algorithms for sparse and black box matrices over finite fields AU - Kaltofen, E. T2 - International Conference on Finite Fields and Applications C2 - 2001/5/23/ CY - Oaxaca, Mexico DA - 2001/5/23/ ER - TY - CHAP TI - Quantitative trait loci: statistical methods for mapping their positions AU - Zeng, Z.-B. T2 - Encyclopedia of Genetics A2 - Reeve, Eric C.R. A2 - Black, Isobel PY - 2001/// PB - Fitzroy Dearborn Publishers SN - 9781884964343 ER - TY - JOUR TI - Cytochrome c is not essential for viability of the fungus Aspergillus nidulans AU - Bradshaw, R.E. AU - Bird, D.M. AU - Brown, S. AU - Gardiner, R.E. AU - Hirst, P. T2 - Molecular Genetics and Genomics DA - 2001/// PY - 2001/// DO - 10.1007/s004380100517 VL - 266 IS - 1 SP - 48-55 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034885798&partnerID=MN8TOARS KW - cytochrome c KW - Aspergillus KW - gene replacement KW - alternative respiration ER - TY - JOUR TI - Impact of integrated nutrient management on growth, yield and nutrient uptake by wheat (Triticum aestivum L.). AU - Akinbile, Christopher O AU - Yusoff, Mohd Suffian AU - Abdullah, MMF AU - El-Hadad, SA AU - Satour, MM AU - Ade-Ademilua, OE AU - Iwaotan, TO AU - Osaji, TC AU - Akinbile, CO AU - Akinbile, CO AU - others T2 - Asian Journal of Agricultural Research DA - 2001/// PY - 2001/// VL - 5 IS - 2 SP - 12-14 ER - TY - CHAP TI - QTL Mapping AU - Zeng, Z.-B. T2 - Encyclopedia of Genetics PY - 2001/// DO - 10.1006/rwgn.2001.1441 SP - 1587-1593 OP - PB - Elsevier SN - 9780122270802 UR - http://dx.doi.org/10.1006/rwgn.2001.1441 DB - Crossref ER - TY - JOUR TI - Phytophthora diseases in forests AU - Frampton, J. T2 - Limbs & Needles DA - 2001/// PY - 2001/// VL - 28 IS - 4 SP - 17-20 ER - TY - CONF TI - North Carolina's Christmas tree genetics program AU - Frampton, J. C2 - 2001/// C3 - Proceedings of the 26th Southern Forest Tree Improvement Conference DA - 2001/// SP - 94-100 ER - TY - JOUR TI - Genetic improvement of Christmas trees AU - Frampton, J. T2 - American Christmas Tree Journal DA - 2001/// PY - 2001/// VL - 48 IS - 2 SP - 16-21 ER - TY - CONF TI - Effects of three propagation systems on survival and growth of loblolly pine and sweetgum rooted cuttings AU - Gocke, M. AU - Goldfarb, B. AU - Robison, D. AU - Frampton, J. C2 - 2001/// C3 - Proceedings of the 26th Biennial Southern Forest Tree Improvement Conference (June 26-29, 2001) DA - 2001/// VL - 26 SP - 29-32 PB - Athens, GA : Georgia Center for Continuing Education, the University of Georgia ER - TY - CONF TI - Comparison of genetic variances estimated from seedlings and rooted cuttings of the same families of Loblolly pine AU - Isik, F. AU - Li, B. AU - Frampton, J. C2 - 2001/// C3 - Proceedings of the 26th Biennial Southern Forest Tree Improvement Conference DA - 2001/// VL - 26 SP - 143-146 PB - Athens, GA : Georgia Center for Continuing Education, the University of Georgia ER - TY - CONF TI - Tree improvement and intensive silviculture - productivity increases from modern plantation methods AU - McKeand, S. E. AU - Allen, H. L. AU - Goldfarb, B. C2 - 2001/// C3 - Proceedings of the 14th CAETS Convocation. World Forests and Technology DA - 2001/// SP - 99-112 ER - TY - CONF TI - Cinnamyl alcohol dehydrogenase (cad) and genomic approaches to manipulating wood properties in loblolly pine AU - O'Malley, D. AU - Scott, J. AU - Harkins, D. AU - Kadia, J. AU - McKeand, S. AU - Chang, H-M C2 - 2001/// C3 - 7th Brazilian Symposium on the Chemistry of Lignins and Other Wood Components DA - 2001/// SP - 19-24 ER - TY - CONF TI - Genetic parameters and uniformity of wood properties of full-sib families and clones of loblolly pine AU - Cumbie, W. P. AU - Li, B. AU - Goldfarb, B. AU - Mullin, T. AU - McKeand, S. C2 - 2001/// C3 - Proceedings of the 26th Southern Forest Tree Improvement Conference DA - 2001/// SP - 104-106 ER - TY - CONF TI - Comparative physiology of contrasting genotypes of loblolly pine under dry field conditions AU - Grissom, J. E. AU - McKeand, S. E. C2 - 2001/// C3 - Proceedings of the 26th Southern Forest Tree Improvement Conference DA - 2001/// SP - 122-124 ER - TY - JOUR TI - Isolation and callus production from cotyledon protoplasts of Cucumis metuliferus AU - McCarthy, W. H. AU - Wehner, T. C. AU - Xie, J. H. AU - Daub, M. E. T2 - Report (Cucurbit Genetics Cooperative) DA - 2001/// PY - 2001/// IS - 24 SP - 102 ER - TY - JOUR TI - Improving culture efficiency of Cucumis metuliferus protoplasts AU - McCarthy, W. H. AU - Wehner, T. C. AU - Xie, J. H. AU - Daub, M. E. T2 - Report (Cucurbit Genetics Cooperative) DA - 2001/// PY - 2001/// IS - 24 SP - 97 ER - TY - PAT TI - Tightly coupled porphyrin macrocycles for molecular memory storage AU - Gryko, D. T. AU - Clausen, P. C. AU - Bocian, D. F. AU - Kuhr, W. G. AU - Lindsey, J. S. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - PAT TI - High density non-volatile memory device incorporating thiol-derivatized porphyrins AU - Gryko, D. T. AU - Clausen, P. C. AU - Roth, K. M. AU - Bocian, D. F. AU - Kuhr, W. G. AU - Lindsey, J. S. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - The genetic architecture of quantitative traits AU - Mackay, TFC T2 - ANNUAL REVIEW OF GENETICS AB - Phenotypic variation for quantitative traits results from the segregation of alleles at multiple quantitative trait loci (QTL) with effects that are sensitive to the genetic, sexual, and external environments. Major challenges for biology in the post-genome era are to map the molecular polymorphisms responsible for variation in medically, agriculturally, and evolutionarily important complex traits; and to determine their gene frequencies and their homozygous, heterozygous, epistatic, and pleiotropic effects in multiple environments. The ease with which QTL can be mapped to genomic intervals bounded by molecular markers belies the difficulty in matching the QTL to a genetic locus. The latter requires high-resolution recombination or linkage disequilibrium mapping to nominate putative candidate genes, followed by genetic and/or functional complementation and gene expression analyses. Complete genome sequences and improved technologies for polymorphism detection will greatly advance the genetic dissection of quantitative traits in model organisms, which will open avenues for exploration of homologous QTL in related taxa. DA - 2001/// PY - 2001/// DO - 10.1146/annurev.genet.35.102401.090633 VL - 35 SP - 303-339 SN - 1545-2948 KW - quantitative trait loci (QTL) KW - quantitative trait nucleotides (QTN) KW - QTL mapping KW - linkage disequilibrium mapping KW - single nucleotide polymorphisms (SNPs) ER - TY - JOUR TI - Rational syntheses of cyclic hexameric porphyrin arrays for studies of self-assembling light-harvesting systems AU - Yu, LH AU - Lindsey, JS T2 - JOURNAL OF ORGANIC CHEMISTRY AB - Two new cyclic hexameric arrays of porphyrins have been prepared in a rational, convergent manner. The porphyrins in each cyclic hexamer are joined by diphenylethyne linkers affording a wheel-like array with a diameter of approximately 35 A. One array is comprised of five zinc (Zn) porphyrins and one free base (Fb) porphyrin (cyclo-Zn(5)FbU) while the other is comprised of an alternating sequence of two Zn porphyrins and one Fb porphyrin (cyclo-Zn(2)FbZn(2)FbU). The prior synthesis employed a one-flask template-directed process and afforded alternating Zn and Fb porphyrins or all Zn porphyrins. More diverse metalation patterns are attractive for manipulating the flow of excited-state energy in the arrays. The rational synthesis of each array employed three Pd-mediated coupling reactions with four tetraarylporphyrin building blocks bearing diethynyl, diiodo, bromo/iodo, or iodo/ethynyl groups. The final ring closure yielding the cyclic hexamer was achieved by reaction of a porphyrin pentamer + porphyrin monomer or the joining of two porphyrin trimers. In the presence of a tripyridyl template, the yields of the 5 + 1 and 3 + 3 reactions ranged from 10 to 13%. The 5 + 1 reaction in the absence of the template proceeded in 3.5% yield, thereby establishing the structure-directed contribution to cyclic hexamer formation. The 3 + 3 route relied on successive ethyne + iodo/bromo coupling reactions. One template-directed route to cyclo-Zn(2)FbZn(2)FbU employed a magnesium porphyrin, affording cyclo-Zn(2)FbZn(2)MgU from which magnesium was selectively removed. The arrays exhibit absorption spectra that are nearly the sum of the spectra of the component parts, indicating weak electronic coupling. Fluorescence spectroscopy showed that the quantum yield of energy transfer in toluene at room temperature from the Zn porphyrins to the Fb porphyrin(s) was 60% in cyclo-Zn(5)FbU and 90% in cyclo-Zn(2)FbZn(2)FbU. Two dipyridyl-substituted porphyrins, a Zn tetraarylporphyrin and a Fb oxaporphyrin, have been synthesized for use as guests in the cyclic hexamers, affording self-assembled arrays for light-harvesting studies. DA - 2001/11/2/ PY - 2001/11/2/ DO - 10.1021/jo010742q VL - 66 IS - 22 SP - 7402-7419 SN - 0022-3263 ER - TY - JOUR TI - Natural history of hypertrophic cardiomyopathy and aortic thromboembolism in a family of domestic shorthair cats AU - Baty, CJ AU - Malarkey, DE AU - Atkins, CE AU - DeFrancesco, TC AU - Sidley, J AU - Keene, BW T2 - JOURNAL OF VETERINARY INTERNAL MEDICINE AB - A feline domestic shorthair queen and her 3 offspring were all diagnosed with asymptomatic hypertrophic cardiomyopathy (HCM). The family has been followed for 13 years, and 3 cats have died of aortic thromboembolism (ATE). This communication documents the long-term progression of HCM in these cats that presented with mild left ventricular hypertrophy and hyperdynamic systolic ventricular function, developed progressive left atrial enlargement, and eventually resulted in hypodynamic left ventricular systolic function with relative left ventricular chamber dilation at the time of ATE. DA - 2001/// PY - 2001/// DO - 10.1892/0891-6640(2001)015<0595:NHOHCA>2.3.CO;2 VL - 15 IS - 6 SP - 595-599 SN - 0891-6640 KW - cardiac myocyte disarray KW - end stage KW - spontaneous echo contrast KW - systolic function KW - ventricular remodeling ER - TY - JOUR TI - Synthesis of meso-substituted chlorins via tetrahydrobilene-a intermediates AU - Taniguchi, M AU - Ra, D AU - Mo, G AU - Balasubramanian, T AU - Lindsey, JS T2 - JOURNAL OF ORGANIC CHEMISTRY AB - Chlorin building blocks incorporating a geminal dimethyl group in the reduced ring and synthetic handles in specific patterns at the perimeter of the macrocycle are expected to have utility in biomimetic and materials chemistry. A prior route employed condensation of a dihydrodipyrrin (Western half) and a bromodipyrromethane-monocarbinol (Eastern half), followed by oxidative cyclization of the putative dihydrobilene-a to form the meso-substituted zinc chlorin in yields of ∼10%. The limited stability of the dihydrodipyrrin precluded study of the chlorin-forming process. We now have refined this methodology. A tetrahydrodipyrrin Western half (2,3,4,5-tetrahydro-1,3,3-trimethyldipyrrin) has been synthesized and found to be quite stable. The condensation of the Western half and an Eastern half (100 mM each) proceeded smoothly in CH3CN containing 100 mM TFA at room temperature for 30 min. The resulting linear tetrapyrrole, a 2,3,4,5-tetrahydrobilene-a, also is quite stable, enabling study of the conversion to chlorin. Refined conditions for the oxidative cyclization were found to include the following: the tetrahydrobilene-a (10 mM), AgTf (3−5 molar equiv), Zn(OAc)2 (15 molar equiv), and 2,2,6,6-tetramethylpiperidine (15 molar equiv) in CH3CN at reflux exposed to air for 4−6 h, affording the zinc chlorin. The chlorin-forming process could be implemented in either a two-flask process or a one-flask process. The two-flask process was applied to form six zinc chlorins bearing substituents such as pentafluorophenyl, 3,5-di-tert-butylphenyl, TMS-ethyl benzoate, iodophenyl, or ethynylphenyl (deprotection of the TMS-ethynyl group occurred during the oxidative cyclization process). The stepwise yields (isolated) for the condensation and oxidative cyclization processes forming the tetrahydrobilene and zinc chlorin were 32−72% and 27−62%, respectively, giving overall yields of zinc chlorin from the Eastern and Western halves of 12−45%. Taken together, the refinements introduced enable 100-mg quantities of chlorin building blocks to be prepared in a facile and rational manner. DA - 2001/11/2/ PY - 2001/11/2/ DO - 10.1021/jo0104835 VL - 66 IS - 22 SP - 7342-7354 SN - 0022-3263 ER - TY - JOUR TI - Investigation of two rational routes for preparing p-phenylene-linked porphyrin trimers AU - Yu, LH AU - Lindsey, JS T2 - TETRAHEDRON AB - Multiporphyrin arrays with p-phenylene linkers, aryl groups at the non-linking meso positions, and no β-substituents are attractive constructs for light-harvesting applications. Condensation of a free base porphyrin-benzaldehyde and 5-mesityldipyrromethane (10 mM each) in CH2Cl2 containing 100 mM TFA at room temperature for 30–40 min followed by oxidation with DDQ afforded a p-phenylene-linked porphyrin trimer in 36% yield. Suzuki coupling of an iodo-porphyrin and a bis(dioxaborolane)-porphyrin (20 and 10 mM, respectively) in toluene/DMF (2:1) containing K2CO3 (8 equiv.) at 90–95°C for ∼20 h afforded the same trimer in 66% yield. The former route was used to prepare a diethynyl substituted p-phenylene-linked porphyrin trimer. While the two routes are somewhat complementary in scope, both are convergent and proceed in a rational manner. DA - 2001/11/5/ PY - 2001/11/5/ DO - 10.1016/S0040-4020(01)00928-0 VL - 57 IS - 45 SP - 9285-9298 SN - 0040-4020 KW - porphyrins and analogues KW - pyrroles KW - Suzuki reactions KW - alkynes ER - TY - JOUR TI - Characterization of a canine model of mucopolysaccharidosis IIIB. AU - Ellinwood, N. M. AU - Wang, P. AU - Skeen, T. AU - Sharp, N. AU - Cesta, M. AU - Bush, W. AU - Hardam, E. AU - Haskins, M. E. AU - Giger, U. T2 - American Journal of Human Genetics DA - 2001/// PY - 2001/// VL - 69 IS - 4 SP - 1760 ER - TY - CONF TI - Altering phosphoinositide metabolism by expressing human type I inositol polyphosphate 5 ' phosphatase in tobacco cells AU - Boss, W. F. AU - Perera, I. Y. AU - Love, J. AU - Heilmann, I. C2 - 2001/// C3 - Molecular Biology of the Cell DA - 2001/// VL - 12 SP - 820 M1 - 2001 Nov ER - TY - JOUR TI - A survey of acid catalysts in dipyrromethanecarbinol condensations leading to meso-substituted porphyrins AU - Geier, GR AU - Callinan, JB AU - Rao, PD AU - Lindsey, JS T2 - JOURNAL OF PORPHYRINS AND PHTHALOCYANINES AB - The successful use of dipyrromethanecarbinols in rational routes to porphyrinic macrocycles requires catalysis conditions that enable irreversible condensation, thereby avoiding substituent scrambling and formation of undesired porphyrin products. Previously, successful conditions of trifluoroacetic acid (TFA) (30 mM) in acetonitrile were identified following a lengthy survey of TFA and BF 3 -etherate catalysis in diverse solvents. In this study, focus was placed on the acid catalyst by examining 17 acids in CH 2 Cl 2 , the traditional solvent for two-step, one-flask porphyrin syntheses. In the self-condensation of the carbinol derived from 1-(4-methylbenzoyl)-5-phenyldipyrromethane, porphyrin yields of 9–55% were obtained from the various acids, compared to 20% under TFA catalysis in acetonitrile. A number of catalytic conditions that produce little to no porphyrin in reactions of pyrrole + benzaldehyde afforded good yields of porphyrin and the suppression of scrambling in reactions of dipyrromethanecarbinols. The four best acid catalysts ( InCl 3 , Sc ( OTf ) 3 , Yb ( OTf ) 3 , and Dy ( OTf ) 3 ) initially identified were then examined with dipyrromethanecarbinols bearing challenging substituents (alkyl, pyridyl, or no substituent). The greatest improvement was obtained with the pyridyl substrates. Selected reactions performed on a preparative scale (115 to 460 mg of isolated porphyrin) verified the results of the analytical-scale experiments and revealed the more facile isolation of the porphyrin from reactions performed in CH 2 Cl 2 rather than acetonitrile. This study provides alternatives to the use of TFA/acetonitrile that offer advantages in terms of yield and isolation of the porphyrin without sacrificing suppression of scrambling. Furthermore, the finding that poor catalysts for the benzaldehyde + pyrrole reaction can be excellent catalysts for dipyrromethanecarbinols provides guidance for the identification of other catalysts for use with reactive precursors in porphyrin-forming reactions. DA - 2001/12// PY - 2001/12// DO - 10.1002/jpp.387 VL - 5 IS - 12 SP - 810-823 SN - 1088-4246 KW - dipyrromethane KW - porphyrin KW - acid catalysis KW - pyridyl KW - lanthanide KW - laser desorption mass spectrometry (LD-MS) ER - TY - JOUR TI - Whole-tree biomass and carbon allocation of juvenile trees of loblolly pine (Pinus taeda): influence of genetics and fertilization AU - Retzlaff, WA AU - Handest, JA AU - DM O'Malley, AU - McKeand, SE AU - Topa, MA T2 - CANADIAN JOURNAL OF FOREST RESEARCH AB - To assess the contribution of belowground biomass allocation towards total carbon (C) allocation of two provenances of loblolly pine (Pinus taeda L.), we examined the total biomass allocation of a fast- and slow-growing family from each provenance. Since planting on a xeric, infertile site in Scotland County, N.C., U.S.A., trees in this study have been subjected to one of two nutrient treatments: optimal nutrition or control (no fertilization). Total biomass of 24 (1 tree/family plot × 2 families × 2 provenances × 2 treatments × 3 blocks) 5-year-old (juvenile) trees was harvested in January 1998. Fertilization increased total root, total shoot, and total tree biomass in all families as compared with harvested trees in control plots. Fertilization also increased biomass of coarse-root, woody-root, taproot, stem, branch, and foliar components of families as compared with trees in control plots. Although there were treatment and family differences in standing-crop biomass of the total root, total shoot, total tree, and various individual root and shoot components, the percent biomass (whole-tree) allocation to these tissues remained similar across treatments. Total nonstructural carbohydrate (TNC) analysis indicated some treatment, family, and provenance differences in TNC concentrations and partitioning to starch and soluble sugars. At the time of harvest, TNC concentrations of belowground tissues were much higher than those of aboveground tissues, and enhanced partitioning towards starch in root tissues indicates an important C storage role for belowground tissues at this time. Indeed, more than 90% of the trees starch content was present in root tissue in January. Although constrained by a sample size of three harvested trees per family, this study suggests that biomass allocation on a whole-tree level was similar between fast- and slow-growing families of different provenances of juvenile loblolly pine and was not affected by fertilizer treatment. DA - 2001/6// PY - 2001/6// DO - 10.1139/x01-017 VL - 31 IS - 6 SP - 960-970 SN - 1208-6037 ER - TY - JOUR TI - Molecular determinants influencing the inheritance of transgenic virus resistance in segregating tobacco families transformed with the nucleocapsid gene of tomato spotted wilt virus AU - Herrero, S AU - Rufty, RC AU - Daub, ME T2 - MOLECULAR BREEDING DA - 2001/// PY - 2001/// DO - 10.1023/A:1011381412397 VL - 7 IS - 2 SP - 131-139 SN - 1572-9788 KW - breeding KW - disease resistance KW - tomato spotted wilt virus KW - tobacco KW - transgenic ER - TY - JOUR TI - Molecular cloning and expression of eight laccase cDNAs in loblolly pine (Pinus taeda) AU - Sato, Y AU - Bao, WL AU - Sederoff, R AU - Whetten, R T2 - JOURNAL OF PLANT RESEARCH DA - 2001/6// PY - 2001/6// DO - 10.1007/PL00013978 VL - 114 IS - 1114 SP - 147-155 SN - 1618-0860 KW - laccase KW - lignin synthesis KW - loblolly pine (Pinus taeda L) KW - xylem differentiation ER - TY - JOUR TI - Immunopathology of Bartonella vinsonii (berkhoffii) in experimentally infected dogs AU - Pappalardo, BL AU - Brown, TT AU - Tompkins, M AU - Breitschwerdt, EB T2 - VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY AB - Following natural infection with Bartonella, dogs and humans develop comparable disease manifestations including endocarditis, peliosis hepatis, and granulomatous disease. As the immunologic response to infection in these hosts has not been clearly established, data presented here was derived from the experimental infection of six specific pathogen free (SPF) beagles with a known pathogenic strain of Bartonella. Six dogs were inoculated intravenously with 10(9)cfu of B. vinsonii ssp. berkhoffii and six control dogs were injected intravenously with an equivalent volume of sterile saline. Despite production of substantial levels of specific antibody, blood culture and molecular analyses indicated that Bartonella established chronic infection in these dogs. Flow cytometric analysis of monocytes indicated impaired bacterial phagocytosis during chronic Bartonella infection. There was also a sustained decrease in the percentage of CD8+ lymphocytes in the peripheral blood. Moreover, modulation of adhesion molecule expression (downregulation of L-selectin, VLA-4, and LFA-1) on CD8+ lymphocytes suggested quantitative and qualitative impairment of this cell subset in Bartonella-infected dogs. When compared with control dogs, flow cytometric analysis of lymph node (LN) cells from B. vinsonii infected dogs revealed an expanded population of CD4+ T cells with an apparent naïve phenotype (CD45RA+/CD62L+/CD49D(dim)). However, fewer B cells from infected dogs expressed cell-surface MHC II, implicating impaired antigen presentation to helper T cells within LN. Taken together, results from this study indicate that B. vinsonii establishes chronic infection in dogs which may result in immune suppression characterized by defects in monocytic phagocytosis, an impaired subset of CD8+ T lymphocytes, and impaired antigen presentation within LN. DA - 2001/12// PY - 2001/12// DO - 10.1016/S0165-2427(01)00372-5 VL - 83 IS - 3-4 SP - 125-147 SN - 1873-2534 KW - dog KW - Bartonella KW - immunosuppression ER - TY - JOUR TI - Brassinosteroids AU - Clouse, S T2 - CURRENT BIOLOGY AB - What are they? Brassinosteroids are polyhydroxlyated sterol derivatives with close structural similarity to animal and insect steroid hormones. They occur at low levels throughout the plant kingdom and regulate the expansion, division and differentiation of cells in young growing tissues. More than 40 brassinosteroids have been identified and characterized from various plant organs, including pollen, seeds, and vegetative shoots. How were they discovered? Researchers at the US Department of Agriculture showed that organic extracts of Brassica napus pollen strongly stimulated cell elongation and division in a bean second-internode assay. The structure of the active component of the B. napus extract was characterized in 1979 and found to be a 28 carbon steroid, given the name brassinolide. Many chemically related compounds have been identified in a range of plant species, and are named brassinosteroids. Brassinolide is the most active and many brassinosteroids are precursors or metabolic products of brassinolide. How are they made? Brassinolide is derived from the membrane sterol campesterol through a series of reductions, hydroxylations, epimerizations and oxidations. There are two major branches of the pathway, termed early and late C-6 oxidation, depending on whether a ketone at carbon 6 is added before or after side chain hydroxylation. Recent evidence suggests that the pathway is more of a metabolic grid than two distinct branches. Many of the genes encoding brassinosteroid biosynthetic enzymes have been cloned in Arabidopsis thaliana and mutants blocking several biosynthetic steps have been identified in Arabidopsis, pea and tomato. How do they work? A complete understanding of the molecular mechanism of brassinosteroid action is still several years away and is a pressing research priority in many laboratories. During cell elongation, a good deal of evidence suggests that brassinosteroids affect the mechanical properties of cell walls, via genomic and non-genomic pathways, to allow turgor-driven cell expansion to proceed. The phenotypes of brassinosteroid-deficient and insensitive mutants confirm that brassinosteroids are essential for cell elongation and also suggest a role in vascular differentiation, senescence, fertility, leaf morphology and light–dark regulation of development. Is there a receptor? The BRI1 gene of Arabidopsis encodes a leucine-rich repeat receptor kinase that has many of the properties expected of a brassinosteroid receptor, or at least a critical component of a receptor complex. Mutations in this gene result in severe developmental phenotypes and biochemical studies have shown that overexpression results in increased binding of labeled brassinosteroid at the cell surface. Whether BRI1 binds brassinosteroid directly or in the presence of another sterol binding protein is unknown. Ligand binding by the extracellular domain of receptor kinases results in autophosphorylation and activation of the intracellular kinase domain. This is followed by phosphorylation of downstream components of the signal transduction pathways. Several substrates of the BRI1 kinase domain have been identified in vitro and experiments are underway to verify if these are indeed in vivo interacting partners of BRI1. Interestingly, plants have conserved the steroid signal but not the classical animal-type intracellular steroid receptor signaling pathway. Do they have commercial potential? Spraying brassinosteroid on a variety of crops including wheat, rice, corn, melons, potatoes, oranges, grapes and pears has in some cases dramaticaly increased yields. Brassinosteroids apparently have more effect when plants are under stress than when grown under optimal conditions. Structurally modified brassinosteroids with greater stability under field conditions have been synthesized and tested in Japan. An inhibitor of brassinosteroid biosynthesis, brassinazole, has also been discovered in Japan and may have some practical utility in slowing plant growth. Where can I find out more? DA - 2001/11/13/ PY - 2001/11/13/ DO - 10.1016/s0960-9822(01)00549-8 VL - 11 IS - 22 SP - R904-R904 SN - 0960-9822 ER - TY - JOUR TI - A single amino acid mutation in the Carnation ringspot virus capsid protein allows virion formation but prevents systemic infection AU - Sit, TL AU - Haikal, PR AU - Callaway, AS AU - Lommel, SA T2 - JOURNAL OF VIROLOGY AB - A Carnation ringspot virus (CRSV) variant (1.26) was identified that accumulates virions but is incapable of forming a systemic infection. The 1.26 capsid protein gene possesses a Ser-->Pro mutation at amino acid 282. Conversion of 1.26 amino acid 282 to Ser restored systemic infection, while the reciprocal mutation in wild-type CRSV abolished systemic infection. Similar mutations introduced into the related Red clover necrotic mosaic virus capsid protein gene failed to induce the packaging but nonsystemic movement phenotype. These results provide additional support for the theory that virion formation is necessary but not sufficient for systemic movement with the dianthoviruses. DA - 2001/10// PY - 2001/10// DO - 10.1128/JVI.75.19.9538-9542.2001 VL - 75 IS - 19 SP - 9538-9542 SN - 0022-538X ER - TY - JOUR TI - Testing for tick-borne diseases in dogs - A roundtable discussion AU - Ford, R. B. AU - Lappin, M. AU - Levy, S. A. AU - Philipp, M. AU - Breitschwerdt, E. T2 - Veterinary Technician DA - 2001/// PY - 2001/// VL - 22 IS - 4 SP - 184-189 ER - TY - JOUR TI - Removal of the pro-domain does not affect the conformation of the procaspase-3 dimer AU - Pop, C AU - Chen, YR AU - Smith, B AU - Bose, K AU - Bobay, B AU - Tripathy, A AU - Franzen, S AU - Clark, AC T2 - BIOCHEMISTRY AB - We have investigated the oligomeric properties of procaspase-3 and a mutant that lacks the pro-domain (called pro-less variant). In addition, we have examined the interactions of the 28 amino acid pro-peptide when added in trans to the pro-less variant. By sedimentation equilibrium studies, we have found that procapase-3 is a stable dimer in solution at 25 degrees C and pH 7.2, and we estimate an upper limit for the equilibrium dissociation constant of approximately 50 nM. Considering the expression levels of caspase-3 in Jurkat cells, we predict that procaspase-3 exists as a dimer in vivo. The pro-less variant is also a dimer, with little apparent change in the equilibrium dissociation constant. Thus, in contrast with the long pro-domain caspases, the pro-peptide of caspase-3 does not appear to be involved in dimerization. Results from circular dichroism, fluorescence anisotropy, and FTIR studies demonstrate that the pro-domain interacts weakly with the pro-less variant. The data suggest that the pro-peptide adopts a beta-structure when in contact with the protein, but it is a random coil when free in solution. In addition, when added in trans, the pro-peptide does not inhibit the activity of the mature caspase-3 heterotetramer. On the other hand, the active caspase-3 does not efficiently hydrolyze the pro-domain at the NSVD(9) sequence as occurs when the pro-peptide is in cis to the protease domain. Based on these results, we propose a model for maturation of the procaspase-3 dimer. DA - 2001/11/27/ PY - 2001/11/27/ DO - 10.1021/bi011037e VL - 40 IS - 47 SP - 14224-14235 SN - 0006-2960 ER - TY - JOUR TI - Recombinant Major Antigenic Protein 2 of Ehrlichia canis: a Potential Diagnostic Tool AU - Alleman, A. R. AU - McSherry, L. J. AU - Barbet, A. F. AU - Breitschwerdt, E. B. AU - Sorenson, H. L. AU - Bowie, M. V. AU - Belanger, M. T2 - Journal of Clinical Microbiology AB - The major antigenic protein 2 (MAP2) of Ehrlichia canis was cloned and expressed. The recombinant protein was characterized and tested in an enzyme-linked immunosorbent assay (ELISA) format for potential application in the serodiagnosis of canine monocytic ehrlichiosis. The recombinant protein, which contained a C-terminal polyhistidine tag, had a molecular mass of approximately 26 kDa. The antigen was clearly identified by Western immunoblotting using antihistidine antibody and immune serum from an experimentally infected dog. The recombinant MAP2 (rMAP2) was tested in an ELISA format using 141 serum samples from E. canis immunofluorescent antibody (IFA)-positive and IFA-negative dogs. Fifty-five of the serum samples were from dogs experimentally or naturally infected with E. canis and were previously demonstrated to contain antibodies reactive with E. canis by indirect immunofluorescence assays. The remaining 86 samples, 33 of which were from dogs infected with microorganisms other than E. canis, were seronegative. All of the samples from experimentally infected animals and 36 of the 37 samples from naturally infected animals were found to contain antibodies against rMAP2 of E. canis in the ELISA. Only 3 of 53 IFA-negative samples tested positive on the rMAP2 ELISA. There was 100% agreement among IFA-positive samples from experimentally infected animals, 97.3% agreement among IFA-positive samples from naturally infected animals, and 94.3% agreement among IFA-negative samples, resulting in a 97.2% overall agreement between the two assays. These data suggest that rMAP2 of E. canis could be used as a recombinant test antigen for the serodiagnosis of canine monocytic ehrlichiosis. DA - 2001/7/1/ PY - 2001/7/1/ DO - 10.1128/JCM.39.7.2494-2499.2001 VL - 39 IS - 7 SP - 2494-2499 J2 - Journal of Clinical Microbiology LA - en OP - SN - 0095-1137 UR - http://dx.doi.org/10.1128/JCM.39.7.2494-2499.2001 DB - Crossref ER - TY - JOUR TI - Quenching of porphyrin excited states by adjacent or distant porphyrin cation radicals in molecular arrays AU - Lammi, RK AU - Ambroise, A AU - Wagner, RW AU - Diers, , JR AU - Bocian, DF AU - Holten, D AU - Lindsey, JS T2 - CHEMICAL PHYSICS LETTERS AB - The quenching of photoexcited porphyrins by porphyrin cation radicals at adjacent or distant sites in diphenylethyne-linked porphyrin dyads and triads has been studied using static and time-resolved optical spectroscopy. The excited-state quenching is highly efficient in all cases (>99%) and occurs in ⩽11 ps between adjacent sites (by through-bond energy/charge transfer) and in ⩽55 ps between distant sites (likely by superexchange-assisted energy transfer). The rates can be tuned using the porphyrin-linker connection motif. These results should prove useful in the design of arrays that use electro- or photo-chemically generated porphyrin cation radicals for molecular switching and other applications in molecular photonics. DA - 2001/6/15/ PY - 2001/6/15/ DO - 10.1016/S0009-2614(01)00452-3 VL - 341 IS - 1-2 SP - 35-44 SN - 0009-2614 ER - TY - JOUR TI - Preliminary interspecific genetic maps of the Populus genome constructed from RAPD markers AU - Yin, TM AU - Huang, MR AU - Wang, MX AU - Zhu, LH AU - Zeng, ZB AU - Wu, RL T2 - GENOME DA - 2001/8// PY - 2001/8// DO - 10.1139/gen-44-4-602 VL - 44 IS - 4 SP - 602-609 SN - 0831-2796 KW - interspecific hybrids KW - linkage map KW - poplar KW - pseudo-testcross mapping strategy ER - TY - JOUR TI - Intervertebral disk disease in 10 cats AU - Munana, KR AU - Olby, NJ AU - Sharp, NJH AU - Skeen, TM T2 - JOURNAL OF THE AMERICAN ANIMAL HOSPITAL ASSOCIATION AB - The medical records of 10 cats diagnosed with intervertebral disk disease were reviewed. No apparent sex or breed predilection was found. The mean age of cats in the study was 9.8 years. Clinical signs included back pain, difficulty ambulating, and incontinence. Radiographs revealed narrowed disk spaces, mineralized intervertebral disks, and evidence of extradural compression on myelography or computed tomography. All intervertebral disk herniations occurred in the thoracolumbar spine, with a peak incidence at the fourth to fifth lumbar (L4-L5) intervertebral disk space. Eight cats had Hansen's type I intervertebral disk herniation. Surgery was performed in seven cats. All cats judged to have an excellent outcome had undergone surgical decompression. DA - 2001/// PY - 2001/// DO - 10.5326/15473317-37-4-384 VL - 37 IS - 4 SP - 384-389 SN - 0587-2871 ER - TY - JOUR TI - FTIR and resonance Raman studies of nitric oxide binding to H93G cavity mutants of myoglobin AU - Thomas, MR AU - Brown, D AU - Franzen, S AU - Boxer, SG T2 - BIOCHEMISTRY AB - Nitric oxide (NO) binds to the myoglobin (Mb) cavity mutant, H93G, forming either a five- or six-coordinate Fe−NO complex. The H93G mutation eliminates the covalent attachment between the protein and the proximal ligand, allowing NO to bind H93G possibly from the proximal side of the heme rather than the typical diatomic binding pocket on the distal side. The question of whether NO binds on the distal or proximal side was addressed by FTIR spectroscopy of the N−O vibrational frequency ν̄N-O for a set of Mb mutants that perturb the electrostatic environment of the heme pocket. Vibrational spectra of five- and six-coordinate MbNO complexes indicate that ν̄N-O shifts (by as much as 26 cm-1) to higher energies for the distal mutants H64V and H64V/H93G relative to the energies of wild-type and H93G MbNO, while ν̄N-O is not affected by the proximal side mutation S92A/H93G. This result suggests that NO binds on the distal side of heme in the five- and six-coordinate MbNO complexes of H93G. Additionally, values of the Fe−NO vibrational frequency ν̄Fe-NO as measured by resonance Raman spectroscopy are reported for the distal and proximal double mutants of H93G. These results suggest that ν̄Fe-NO is not very sensitive to mutations that perturb the electrostatic environment of the heme pocket, leading to the observation that ν̄N-O and ν̄Fe-NO are not quantitatively correlated for the MbNO complexes presented here. Furthermore, ν̄N-O and ν̄Fe-NO do not correlate well with equilibrium constants for imidazole binding to the five-coordinate MbNO complexes of the H93G double mutants. The data presented here do not appear to support the presence of π-back-bonding or an inverse trans effect of NO binding in Mb mutants that alter the electrostatic environment of the heme pocket. DA - 2001/12/11/ PY - 2001/12/11/ DO - 10.1021/bi011440l VL - 40 IS - 49 SP - 15047-15056 SN - 0006-2960 ER - TY - JOUR TI - Elucidation of new structures in lignins of CAD- and COMT-deficient plants by NMR AU - Ralph, J AU - Lapierre, C AU - Marita, JM AU - Kim, H AU - Lu, FC AU - Hatfield, RD AU - Ralph, S AU - Chapple, C AU - Franke, R AU - Hemm, MR AU - Van Doorsselaere, J AU - Sederoff, RR AU - DM O'Malley, AU - Scott, JT AU - MacKay, JJ AU - Yahiaoui, N AU - Boudet, AM AU - Pean, M AU - Pilate, G AU - Jouanin, L AU - Boerjan, W T2 - PHYTOCHEMISTRY AB - Studying lignin-biosynthetic-pathway mutants and transgenics provides insights into plant responses to perturbations of the lignification system, and enhances our understanding of normal lignification. When enzymes late in the pathway are downregulated, significant changes in the composition and structure of lignin may result. NMR spectroscopy provides powerful diagnostic tools for elucidating structures in the difficult lignin polymer, hinting at the chemical and biochemical changes that have occurred. COMT (caffeic acid O-methyl transferase) downregulation in poplar results in the incorporation of 5-hydroxyconiferyl alcohol into lignins via typical radical coupling reactions, but post-coupling quinone methide internal trapping reactions produce novel benzodioxane units in the lignin. CAD (cinnamyl alcohol dehydrogenase) downregulation results in the incorporation of the hydroxycinnamyl aldehyde monolignol precursors intimately into the polymer. Sinapyl aldehyde cross-couples 8-O-4 with both guaiacyl and syringyl units in the growing polymer, whereas coniferyl aldehyde cross-couples 8-O-4 only with syringyl units, reflecting simple chemical cross-coupling propensities. The incorporation of hydroxycinnamyl aldehyde and 5-hydroxyconiferyl alcohol monomers indicates that these monolignol intermediates are secreted to the cell wall for lignification. The recognition that novel units can incorporate into lignins portends significantly expanded opportunities for engineering the composition and consequent properties of lignin for improved utilization of valuable plant resources. DA - 2001/7// PY - 2001/7// DO - 10.1016/S0031-9422(01)00109-1 VL - 57 IS - 6 SP - 993-1003 SN - 0031-9422 KW - NMR KW - transgenic KW - mutant KW - O-methyltransferase KW - monolignol KW - coniferyl aldehyde KW - sinapyl aldehyde KW - 5-hydroxyconiferyl alcohol ER - TY - PCOMM TI - Dwarf8 polymorphisms associate with variation in flowering time AU - Thornsberry, JM AU - Goodman, MM AU - Doebley, J AU - Kresovich, S AU - Nielsen, D AU - Buckler, ES DA - 2001/7// PY - 2001/7// DO - 10.1038/90135 SP - 286-289 ER - TY - JOUR TI - Development of a functional scoring system in dogs with acute spinal cord injuries AU - Olby, NJ AU - De Risio, L AU - Munana, KR AU - Wosar, MA AU - Skeen, TM AU - Sharp, NJH AU - Keene, BW T2 - AMERICAN JOURNAL OF VETERINARY RESEARCH AB - To develop and compare the reliability of 2 methods of scoring pelvic limb gait in dogs recovering from thoracolumbar spinal cord injuries and to use this scoring system to determine the rate and level of functional recovery of dogs with acute thoracolumbar intervertebral disk herniations.46 dogs with spinal cord injuries resulting from intervertebral disk herniations.Dogs' gaits were videotaped at different time intervals after injury. In phase 1 of the study, the stages of recovery of pelvic limb function were identified, and a numeric scoring system was devised to reflect that recovery. In phase 2, pelvic limb gait was scored by different observers, using a numeric and a visual analog scale. Intra- and interobserver coefficients of variability of both methods were compared. In phase 3, pelvic limb function was scored, using the numeric scale at various intervals after acute thoracolumbar disk herniations.The numeric scale was significantly more reliable than the visual analog scale when both intra- and interobserver coefficients of variability were evaluated. Dogs that were paraplegic with no deep pain sensation recovered at different rates during the first 3 months, whereas dogs that were paraplegic with deep pain sensation typically recovered within 1 month of injury.Pelvic limb gait of dogs recovering from thoracolumbar spinal cord injuries can be reliably quantified, using a numeric scale. This scale will facilitate the performance of clinical trials aimed at improving the outcome of acute spinal cord injuries. DA - 2001/10// PY - 2001/10// DO - 10.2460/ajvr.2001.62.1624 VL - 62 IS - 10 SP - 1624-1628 SN - 1943-5681 ER - TY - JOUR TI - Can simultaneous inhibition of seedling growth and stimulation of rhizosphere bacterial populations provide evidence for phytotoxin transfer from plant residues in the bulk soil to the rhizosphere of sensitive species? AU - Staman, K AU - Blum, U AU - Louws, F AU - Robertson, D T2 - JOURNAL OF CHEMICAL ECOLOGY DA - 2001/4// PY - 2001/4// DO - 10.1023/A:1010362221390 VL - 27 IS - 4 SP - 807-829 SN - 1573-1561 KW - allelopathy KW - bulk-soil and rhizosphere bacteria KW - Cucumis sativus KW - Helianthus annuus KW - Triticum aestivum KW - Amaranthus retroflexus KW - phenolic acid mixtures KW - chlorogenic acid KW - phytotoxicity ER - TY - JOUR TI - Accelerated regulatory gene evolution in an adaptive radiation AU - Barrier, M AU - Robichaux, RH AU - Purugganan, MD T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - The disparity between rates of morphological and molecular evolution remains a key paradox in evolutionary genetics. A proposed resolution to this paradox has been the conjecture that morphological evolution proceeds via diversification in regulatory loci, and that phenotypic evolution may correlate better with regulatory gene divergence. This conjecture can be tested by examining rates of regulatory gene evolution in species that display rapid morphological diversification within adaptive radiations. We have isolated homologues to the Arabidopsis APETALA3 (ASAP3/TM6) and APETALA1 (ASAP1) floral regulatory genes and the CHLOROPHYLL A/B BINDING PROTEIN9 (ASCAB9) photosynthetic structural gene from species in the Hawaiian silversword alliance, a premier example of plant adaptive radiation. We have compared rates of regulatory and structural gene evolution in the Hawaiian species to those in related species of North American tarweeds. Molecular evolutionary analyses indicate significant increases in nonsynonymous relative to synonymous nucleotide substitution rates in the ASAP3/TM6 and ASAP1 regulatory genes in the rapidly evolving Hawaiian species. By contrast, no general increase is evident in neutral mutation rates for these loci in the Hawaiian species. An increase in nonsynonymous relative to synonymous nucleotide substitution rate is also evident in the ASCAB9 structural gene in the Hawaiian species, but not to the extent displayed in the regulatory loci. The significantly accelerated rates of regulatory gene evolution in the Hawaiian species may reflect the influence of allopolyploidy or of selection and adaptive divergence. The analyses suggest that accelerated rates of regulatory gene evolution may accompany rapid morphological diversification in adaptive radiations. DA - 2001/8/28/ PY - 2001/8/28/ DO - 10.1073/pnas.181257698 VL - 98 IS - 18 SP - 10208-10213 SN - 0027-8424 KW - floral regulatory loci KW - MADS-box KW - CAB9 KW - Hawaiian silversword alliance ER - TY - JOUR TI - Tick-borne infectious diseases of dogs AU - Shaw, SE AU - Day, MJ AU - Birtles, RJ AU - Breitschwerdt, EB T2 - TRENDS IN PARASITOLOGY AB - Tick-transmitted infections are an emerging problem in dogs. In addition to causing serious disease in traditional tropical and semi-tropical regions, they are now increasingly recognized as a cause of disease in dogs in temperate climates and urban environments. Furthermore, subclinically infected companion animals could provide a reservoir for human tick-transmitted infectious agents, such as Ehrlichia chaffeensis, Ehrlichia ewingii, the Ehrlichia phagocytophila group and Rickettsia conorii. Here, we discuss the emergence of new canine tick-transmitted diseases, which results from several factors, including the expansion of the tick range into urban and semi-urban areas worldwide, the movement of infected dogs into previously non-endemic areas, and the advent of novel molecular techniques for diagnosis and pathogen identification. DA - 2001/2// PY - 2001/2// DO - 10.1016/S1471-4922(00)01856-0 VL - 17 IS - 2 SP - 74-80 SN - 1471-5007 ER - TY - JOUR TI - The Ca2+ status of the endoplasmic reticulum is altered by induction of calreticulin expression in transgenic plants AU - Persson, S AU - Wyatt, SE AU - Love, J AU - Thompson, WF AU - Robertson, D AU - Boss, WF T2 - PLANT PHYSIOLOGY AB - Abstract To investigate the endoplasmic reticulum (ER) Ca2+ stores in plant cells, we generated tobacco (Nicotiana tabacum; NT1) suspension cells and Arabidopsis plants with altered levels of calreticulin (CRT), an ER-localized Ca2+-binding protein. NT1 cells and Arabidopsis plants were transformed with a maize (Zea mays) CRT gene in both sense and antisense orientations under the control of an Arabidopsis heat shock promoter. ER-enriched membrane fractions from NT1 cells were used to examine how altered expression of CRT affects Ca2+uptake and release. We found that a 2.5-fold increase in CRT led to a 2-fold increase in ATP-dependent 45Ca2+accumulation in the ER-enriched fraction compared with heat-shocked wild-type controls. Furthermore, after treatment with the Ca2+ ionophore ionomycin, ER microsomes from NT1 cells overproducing CRT showed a 2-fold increase in the amount of45Ca2+ released, and a 2- to 3-fold increase in the amount of 45Ca2+ retained compared with wild type. These data indicate that altering the production of CRT affects the ER Ca2+ pool. In addition, CRTtransgenic Arabidopsis plants were used to determine if altered CRT levels had any physiological effects. We found that the level of CRT in heat shock-induced CRT transgenic plants correlated positively with the retention of chlorophyll when the plants were transferred from Ca2+-containing medium to Ca2+-depleted medium. Together these data are consistent with the hypothesis that increasing CRT in the ER increases the ER Ca2+ stores and thereby enhances the survival of plants grown in low Ca2+ medium. DA - 2001/7// PY - 2001/7// DO - 10.1104/pp.126.3.1092 VL - 126 IS - 3 SP - 1092-1104 SN - 1532-2548 ER - TY - JOUR TI - Stochasticity in transcriptional regulation: Origins, consequences, and mathematical representations AU - Kepler, TB AU - Elston, TC T2 - BIOPHYSICAL JOURNAL AB - Transcriptional regulation is an inherently noisy process. The origins of this stochastic behavior can be traced to the random transitions among the discrete chemical states of operators that control the transcription rate and to finite number fluctuations in the biochemical reactions for the synthesis and degradation of transcripts. We develop stochastic models to which these random reactions are intrinsic and a series of simpler models derived explicitly from the first as approximations in different parameter regimes. This innate stochasticity can have both a quantitative and qualitative impact on the behavior of gene-regulatory networks. We introduce a natural generalization of deterministic bifurcations for classification of stochastic systems and show that simple noisy genetic switches have rich bifurcation structures; among them, bifurcations driven solely by changing the rate of operator fluctuations even as the underlying deterministic system remains unchanged. We find stochastic bistability where the deterministic equations predict monostability and vice-versa. We derive and solve equations for the mean waiting times for spontaneous transitions between quasistable states in these switches. DA - 2001/12// PY - 2001/12// DO - 10.1016/S0006-3495(01)75949-8 VL - 81 IS - 6 SP - 3116-3136 SN - 0006-3495 ER - TY - JOUR TI - Ribosome-inactivating proteins: A plant perspective AU - Nielsen, K AU - Boston, RS T2 - ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY AB - Ribosome-inactivating proteins (RIPs) are toxic N-glycosidases that depurinate the universally conserved alpha-sarcin loop of large rRNAs. This depurination inactivates the ribosome, thereby blocking its further participation in protein synthesis. RIPs are widely distributed among different plant genera and within a variety of different tissues. Recent work has shown that enzymatic activity of at least some RIPs is not limited to site-specific action on the large rRNAs of ribosomes but extends to depurination and even nucleic acid scission of other targets. Characterization of the physiological effects of RIPs on mammalian cells has implicated apoptotic pathways. For plants, RIPs have been linked to defense by antiviral, antifungal, and insecticidal properties demonstrated in vitro and in transgenic plants. How these effects are brought about, however, remains unresolved. At the least, these results, together with others summarized here, point to a complex biological role. With genetic, genomic, molecular, and structural tools now available for integrating different experimental approaches, we should further our understanding of these multifunctional proteins and their physiological functions in plants. DA - 2001/// PY - 2001/// DO - 10.1146/annurev.arplant.52.1.785 VL - 52 SP - 785-816 SN - 1040-2519 KW - RIP KW - protein synthesis inhibitor KW - plant toxins KW - cytotoxicity KW - 28S ribosomal RNA ER - TY - JOUR TI - Proliferating cell nuclear antigen transcription is repressed through an E2F consensus element and activated by geminivirus infection in mature leaves AU - Egelkrout, EM AU - Robertson, D AU - Hanley-Bowdoin, L T2 - PLANT CELL AB - The geminivirus tomato golden mosaic virus (TGMV) amplifies its DNA genome in differentiated plant cells that lack detectable levels of DNA replication enzymes. Earlier studies showed that TGMV induces the accumulation of proliferating cell nuclear antigen (PCNA), the processivity factor for DNA polymerase delta, in mature cells of Nicotiana benthamiana. We sought to determine if PCNA protein accumulation reflects transcriptional activation of the host gene. RNA gel blot analysis detected an approximately 1200-nucleotide PCNA transcript in young leaves. The same RNA was found in mature leaves of infected but not healthy plants. Reporter gene analysis showed that a 633-bp promoter fragment of the N. benthamiana PCNA gene supports high levels of expression in cultured cells and in young but not mature leaves of healthy transgenic plants. In contrast, PCNA promoter activity was detected in both young and mature leaves of TGMV-infected plants. Developmental studies established a strong relationship between symptom severity, viral DNA accumulation, PCNA promoter activity, and endogenous PCNA mRNA levels. Mutation of an E2F consensus element in the PCNA promoter had no effect on its activity in young leaves but increased transcription in healthy mature leaves. Unlike the wild-type PCNA promoter, TGMV infection had no detectable effect on the activity of the mutant E2F promoter. Together, these results demonstrate that geminivirus infection induces the accumulation of a host replication factor by activating transcription of its gene in mature tissues, most likely by overcoming E2F-mediated repression. DA - 2001/6// PY - 2001/6// DO - 10.1105/tpc.13.6.1437 VL - 13 IS - 6 SP - 1437-1452 SN - 1531-298X ER - TY - PAT TI - Method for reducing expression variability of transgenes in plant cells AU - Thompson, W. F. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Isolation of PDX2, a second novel gene in the pyridoxine biosynthesis pathway of eukaryotes, archaebacteria, and a subset of eubacteria AU - Ehrenshaft, M AU - Daub, ME T2 - JOURNAL OF BACTERIOLOGY AB - In this paper we describe the isolation of a second gene in the newly identified pyridoxine biosynthesis pathway of archaebacteria, some eubacteria, fungi, and plants. Although pyridoxine biosynthesis has been thoroughly examined in Escherichia coli, recent characterization of the Cercospora nicotianae biosynthesis gene PDX1 led to the discovery that most organisms contain a pyridoxine synthesis gene not found in E. coli. PDX2 was isolated by a degenerate primer strategy based on conserved sequences of a gene specific to PDX1-containing organisms. The role of PDX2 in pyridoxine biosynthesis was confirmed by complementation of two C. nicotianae pyridoxine auxotrophs not mutant in PDX1. Also, targeted gene replacement of PDX2 in C. nicotianae results in pyridoxine auxotrophy. Comparable to PDX1, PDX2 homologues are not found in any of the organisms with homologues to the E. coli pyridoxine genes, but are found in the same archaebacteria, eubacteria, fungi, and plants that contain PDX1 homologues. PDX2 proteins are less well conserved than their PDX1 counterparts but contain several protein motifs that are conserved throughout all PDX2 proteins. DA - 2001/6// PY - 2001/6// DO - 10.1128/JB.183.11.3383-3390.2001 VL - 183 IS - 11 SP - 3383-3390 SN - 0021-9193 ER - TY - JOUR TI - Investigation of porphyrin-forming reactions. Part 4. Examination of the reaction course in syntheses of porphyrins via dipyrromethanecarbinols AU - Geier, GR AU - Littler, BJ AU - Lindsey, JS T2 - JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 AB - The dipyrromethanecarbinol motif is a key component in rational routes to a wide variety of porphyrinic macrocycles. We have investigated the dipyrromethane-monocarbinol self-condensation and the dipyrromethane-dicarbinol + dipyrromethane condensation under four different acid-catalysis conditions and have characterized the oligomer composition (by LD-MS), yield of porphyrin (by UV–Vis), and yield of N-confused porphyrin (by HPLC). Under conditions giving “no-scrambling”, the condensations are rapid and afford an oligomer composition characterized by (1) absence of scrambling, (2) suppression of acidolysis, and (3) a disproportionate amount of long oligomers from which recovery does not occur. The irreversibility of the reaction and lack of recovery from the long oligomers may explain the lower yields of dipyrromethanecarbinol condensations (<30%) compared with reversible reactions of aldehyde + pyrrole (∼50%). Modest levels of acidolysis and scrambling with the dipyrromethanecarbinols are obtained under reaction conditions that cause extensive scrambling in dipyrromethane + aldehyde condensations. Because both reactions give the same porphyrinogen, the scrambling processes must primarily involve the dipyrromethane or oligomer intermediates rather than the porphyrinogen. The dipyrromethane-monocarbinol self-condensation and dipyrromethane-dicarbinol + dipyrromethane condensation afford quite similar oligomer compositions, suggesting that both follow similar pathways to the porphyrinogen. Reaction conditions that suppress scrambling in the dipyrromethanecarbinol condensations were found to dramatically suppress formation of the N-confused porphyrin. Taken together, these experiments show how the greater reactivity of the dipyrromethanecarbinol unit (compared with the pyrrole + aldehyde reaction) facilitates synthesis of meso-substituted porphyrins without scrambling. DA - 2001/// PY - 2001/// DO - 10.1039/b009101o IS - 5 SP - 712-718 SN - 1472-779X ER - TY - JOUR TI - Investigation of porphyrin-forming reactions. Part 3. The origin of scrambling in dipyrromethane plus aldehyde condensations yielding trans-A(2)B(2)-tetraarylporphyrins AU - Geier, GR AU - Littler, BJ AU - Lindsey, JS T2 - JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 AB - The dipyrromethane + aldehyde condensation is a common method for the synthesis of trans-A2B2-porphyrins, but is often plagued by scrambling processes that lead to a mixture of porphyrins. The problem of scrambling is more pronounced with unhindered dipyrromethanes (e.g., 5-phenyldipyrromethane) than with hindered dipyrromethanes (e.g., 5-mesityldipyrromethane). We have characterized the oligomer composition (by LD-MS), yield of porphyrin (by UV–Vis), yield of N-confused porphyrin (by HPLC), and level of unreacted aldehyde (by TLC) in dipyrromethane + aldehyde condensations leading to trans-A2B2-porphyrins. Reaction conditions known to suppress scrambling in reactions involving 5-phenyldipyrromethane (PDPM) were compared to conditions known to provide extensive scrambling. The low-scrambling conditions were found to suppress scrambling by inhibiting reaction of oligomer fragments generated by acid-induced cleavage of the dipyrromethane, rather than by inhibiting acidolysis itself. However, such reaction conditions were also found to inhibit the condensation, leading to low yields (<10%) of porphyrin. The condensation of PDPM + aldehyde was also compared to reactions involving 5-mesityldipyrromethane (MDPM) to understand why trans-A2B2-porphyrins can be prepared in good yield devoid of scrambling from reactions using MDPM. The absence of scrambling in MDPM + aldehyde condensations was due to the resistance of MDPM to acidolysis. Taken together, these studies provide insight into the origin of scrambling with different types of substrates under different reaction conditions in the dipyrromethane + aldehyde route to trans-A2B2-porphyrins. DA - 2001/// PY - 2001/// DO - 10.1039/b009098k IS - 5 SP - 701-711 SN - 1472-779X ER - TY - JOUR TI - Investigation of porphyrin-forming reactions. Part 2. Examination of the reaction course in two-step, one-flask syntheses of meso-substituted porphyrins AU - Geier, GR AU - Lindsey, JS T2 - JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 AB - The reaction course leading to meso-substituted porphyrins was examined for reversibility (formation of oligomers, formation of α- and β-pyrrole linkages), inactivation of the acid catalyst, homogeneity of the reaction medium, and the pathway of oligomer formation. The methodology employed enabled characterization of the oligomer composition (LD-MS), yield of porphyrin (UV–Vis), yield of N-confused porphyrin (HPLC), and level of unreacted aldehyde (TLC). Experiments were performed with benzaldehyde and pyrrole with catalysis by TFA or BF3–Et2O. Key observations include the following. (1) Reactions with BF3–Et2O exhibited reversible exchange of oligomers throughout the reaction. With TFA, the oligomer exchange processes were reversible at short reaction times, but became largely irreversible over the course of several hours. (2) The BF3–Et2O activity declined during the course of the reaction, whereas that of TFA was little changed. (3) The reaction medium remained homogeneous at 10 mM pyrrole + aldehyde. (4) Dipyrromethanes comprised of α- but not β-linkages underwent cleavage with either TFA or BF3–Et2O. (5) Condensations with carbinol intermediates (pyrrole-carbinol, dipyrromethane-monocarbinol, dipyrromethane-dicarbinol) provided rapid reactions, lower yields of porphyrin, and longer oligomers than typical in reactions of pyrrole + benzaldehyde. Higher porphyrin yields were obtained with BF3–Et2O than TFA, which is attributed to the more facile recovery from longer oligomers with the former versus the latter catalyst. Collectively, these and other observations lead to a model for the aldehyde + pyrrole condensation comprised of a combination of irreversible and reversible reactions in oligomer formation, irreversible side reactions (formation of dipyrrins, β-linkages), and slow inactivation of the catalyst (BF3–Et2O). DA - 2001/// PY - 2001/// DO - 10.1039/b009092l IS - 5 SP - 687-700 SN - 1472-779X ER - TY - JOUR TI - Investigation of porphyrin-forming reactions. Part 1. Pyrrole plus aldehyde oligomerization in two-step, one-flask syntheses of meso-substituted porphyrins AU - Geier, GR AU - Lindsey, JS T2 - JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2 AB - A deep understanding of the two-step, one-flask synthesis of meso-substituted porphyrins requires characterization of the acyclic oligomers, which typically constitute ≥50% of the products. We have employed laser desorption mass spectrometry (LD-MS) to obtain a qualitative yet high resolution view of the oligomer content of crude oxidized reaction mixtures. This methodology complements other analytical methods which provide information regarding yields of porphyrin, other macrocyclic products, and unreacted aldehyde. Our findings include the following. (1) Crude oxidized porphyrin reaction mixtures provided peaks in the LD-MS spectrum which were readily assigned to oligomers (m/z 100–2000) derived from pyrrole–aldehyde condensation. The oligomers comprised one of four series depending on the ratio of pyrrole and aldehyde units. (2) Quite disparate reaction conditions that gave good yields of porphyrin also afforded a similar oligomer composition. (3) The change in the nature of the oligomers over time was readily monitored. (4) The maximum yield of porphyrin and the maximum diversity of the oligomer composition were attained at similar times. (5) The decline in yield of porphyrin at long reaction time was accompanied by truncation, not elongation, of oligomers. (6) The onset of the truncation of oligomers and the decline in yield of porphyrin were accompanied by a decrease of the aldehyde to low levels. (7) Pyrrole was incorporated into the growing oligomers more rapidly than aldehyde. Taken together, these studies show how various conditions alter the course of the pyrrole–aldehyde condensation. DA - 2001/// PY - 2001/// DO - 10.1039/b009088n IS - 5 SP - 677-686 SN - 1472-779X ER - TY - JOUR TI - Induction of lipid metabolic enzymes during the endoplasmic reticulum stress response in plants AU - Shank, KJ AU - Su, P AU - Brglez, I AU - Boss, WF AU - Dewey, RE AU - Boston, RS T2 - PLANT PHYSIOLOGY AB - Abstract The endoplasmic reticulum (ER) stress response is a signal transduction pathway activated by the perturbation of normal ER metabolism. We used the maize (Zea mays)floury-2 (fl2) mutant and soybean (Glycine max) suspension cultures treated with tunicamycin (Tm) to investigate the ER stress response as it relates to phospholipid metabolism in plants. Four key phospholipid biosynthetic enzymes, including DG kinase and phosphatidylinositol (PI) 4-phosphate 5-kinase were up-regulated in the fl2 mutant, specifically in protein body fractions where the mutation has its greatest effect. The third up-regulated enzyme, choline-phosphate cytidylyltransferase, was regulated by fl2 gene dosage and developmental signals. Elevated accumulation of the fourth enzyme, PI 4-kinase, was observed in the fl2 endosperm and soybean cells treated with Tm. The activation of these phospholipid biosynthetic enzymes was accompanied by alterations in membrane lipid synthesis and accumulation. The fl2 mutant exhibited increased PI content in protein body membranes at 18 d after pollination and more than 3-fold higher triacylglycerol accumulation in the endosperm by 36 d after pollination. Incorporation of radiolabeled acetate into phospholipids in soybean culture cells increased by about 30% with Tm treatment. The coordinated regulation of ER stress related proteins and multiple components of phospholipid biosynthesis is consistent with signaling through a common pathway. We postulate that the plant ER stress response has an important role in general plant metabolism, and more specifically in integrating the synthesis of protein and lipid reserves to allow proper seed formation. DA - 2001/5// PY - 2001/5// DO - 10.1104/pp.126.1.267 VL - 126 IS - 1 SP - 267-277 SN - 0032-0889 ER - TY - JOUR TI - Functional genomics and cell wall biosynthesis in loblolly pine AU - Whetten, R AU - Sun, YH AU - Zhang, Y AU - Sederoff, R T2 - PLANT MOLECULAR BIOLOGY DA - 2001/// PY - 2001/// DO - 10.1023/A:1010652003395 VL - 47 IS - 1-2 SP - 275-291 SN - 1573-5028 KW - EST sequencing KW - microarrays KW - Pinus taeda KW - xylogenesis KW - wood formation ER - TY - JOUR TI - A role for inositol 1,4,5-trisphosphate in gravitropic signaling and the retention of cold-perceived gravistimulation of oat shoot pulvini AU - Perera, IK AU - Hilmann, I AU - Chang, SC AU - Boss, WF AU - Kaufman, PB T2 - PLANT PHYSIOLOGY AB - Abstract Plants sense positional changes relative to the gravity vector. To date, the signaling processes by which the perception of a gravistimulus is linked to the initiation of differential growth are poorly defined. We have investigated the role of inositol 1,4,5-trisphosphate (InsP3) in the gravitropic response of oat (Avena sativa) shoot pulvini. Within 15 s of gravistimulation, InsP3 levels increased 3-fold over vertical controls in upper and lower pulvinus halves and fluctuated in both pulvinus halves over the first minutes. Between 10 and 30 min of gravistimulation, InsP3 levels in the lower pulvinus half increased 3-fold over the upper. Changes in InsP3 were confined to the pulvinus and were not detected in internodal tissue, highlighting the importance of the pulvinus for both graviperception and response. Inhibition of phospholipase C blocked the long-term increase in InsP3, and reduced gravitropic bending by 65%. Short-term changes in InsP3 were unimpaired by the inhibitor. Gravitropic bending of oat plants is inhibited at 4°C; however, the plants retain the information of a positional change and respond at room temperature. Both short- and long-term changes in InsP3 were present at 4°C. We propose a role for InsP3 in the establishment of tissue polarity during the gravitropic response of oat pulvini. InsP3 may be involved in the retention of cold-perceived gravistimulation by providing positional information in the pulvini prior to the redistribution of auxin. DA - 2001/3// PY - 2001/3// DO - 10.1104/pp.125.3.1499 VL - 125 IS - 3 SP - 1499-1507 SN - 1532-2548 ER - TY - JOUR TI - The multifunctional capsid proteins of plant RNA viruses AU - Callaway, A AU - Giesman-Cookmeyer, D AU - Gillock, ET AU - Sit, TL AU - Lommel, SA T2 - ANNUAL REVIEW OF PHYTOPATHOLOGY AB - This article summarizes studies of viral coat (capsid) proteins (CPs) of RNA plant viruses. In addition, we discuss and seek to interpret the knowledge accumulated to data. CPs are named for their primary function; to encapsidate viral genomic nucleic acids. However, encapsidation is only one feature of an extremely diverse array of structural, functional, and ecological roles played during viral infection and spread. Herein, we consider the evolution of viral CPs and their multitude of interactions with factors encoded by the virus, host plant, or viral vector (biological transmission agent) that influence the infection and epidemiological facets of plant disease. In addition, applications of today's understanding of CPs in the protection of crops from viral infection and use in the manufacture of valuable compounds are considered. DA - 2001/// PY - 2001/// DO - 10.1146/annurev.phyto.39.1.419 VL - 39 SP - 419-+ SN - 1545-2107 KW - evolution KW - movement KW - transmission KW - resistance KW - host-factors KW - biotechnology ER - TY - JOUR TI - Quantitative trait locus mapping of fitness-related traits in Drosophila melanogaster AU - Wayne, ML AU - Hackett, JB AU - Dilda, CL AU - Nuzhdin, SV AU - Pasyukova, EG AU - MacKay, TFC T2 - GENETICAL RESEARCH AB - We examined the genetic architecture of four fitness-related traits (reproductive success, ovariole number, body size and early fecundity) in a panel of 98 Oregon-R x 2b3 recombinant inbred lines (RILs). Highly significant genetic variation was observed in this population for female, but not male, reproductive success. The cross-sex genetic correlation for reproductive success was 0.20, which is not significantly different from zero. There was significant genetic variation segregating in this cross for ovariole number, but not for body size or early fecundity. The RILs were genotyped for cytological insertion sites of roo transposable elements, yielding 76 informative markers with an average spacing of 3.2 cM. Quantitative trait loci (QTL) affecting female reproductive success and ovariole number were mapped using a composite interval mapping procedure. QTL for female reproductive success were located at the tip of the X chromosome between markers at cytological locations 1B and 3E; and on the left arm of chromosome 2 in the 30D-38A cytological region. Ovariole number QTL mapped to cytological intervals 62D-69D and 98A-98E, both on the third chromosome. The regions harbouring QTL for female reproductive success and ovariole number were also identified as QTL for longevity in previous studies with these lines. DA - 2001/2// PY - 2001/2// DO - 10.1017/S0016672300004894 VL - 77 IS - 1 SP - 107-116 SN - 0016-6723 ER - TY - JOUR TI - Provenance variation and provenance-site interaction in Pinusbrutia TEN.: Consequences of defining breeding zones AU - Isik, F. AU - Keskin, S. AU - McKeand, S. E. T2 - Silvae Genetica DA - 2001/// PY - 2001/// VL - 49 IS - 4-5 SP - 213-223 ER - TY - JOUR TI - Olfaction in Drosophila: from receptors to behavior AU - Anholt, R T2 - CHEMICAL SENSES DA - 2001/2// PY - 2001/2// DO - 10.1093/chemse/26.2.193 VL - 26 IS - 2 SP - 193-193 SN - 0379-864X ER - TY - JOUR TI - Metabolic mechanisms associated with alleles governing the 16 : 0 concentration of soybean oil AU - Wilson, RF AU - Marquardt, TC AU - Novitzky, WP AU - Burton, JW AU - Wilcox, , JR AU - Kinney, AJ AU - Dewey, RE T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Soybean [ Glycine max (L.) Merr.] oil typically contains ca. 11% palmitic acid, but germplasm has been developed with less than 4% to about 35% 16∶0, A number of recessive alleles associated with these phenotypes have been described thattrepresent different mutations at Fap loci, however, the gene products (enzymes) produced by these alleles are unknown. This work attempts to define the metabolic activities that are regulated by the fap 1 , fap 2 , and fap nc alleles in soybean. Observation of de novo synthesis and metabolic turnover of fatty acids esterified to phospholipids in cotyledons during the period of peak oil accumulation revealed genotypic differences in the supply of 16∶0‐CoA from plastids. These metabolic studies narrowed the identification of fap 1 , fap 2 , and fap nc alleles to the genes that encode or regulate the 3‐keto‐acyl‐ACP synthetase II (where ACP is acyl carrier protein), 16∶0‐ACP thioesterase, 18∶0‐ACP desaturase, or 18∶1‐ACP thioesterase enzymes. Kinetic analyses suggested that the fap 2 mutation results in a decreased 3‐keto‐acyl‐ACP synthetase II activity. Deficiencies in 16∶0‐ACP thioesterase activity represented the most likely explanation of fap 1 and fap nc gene function. This hypothesis was strongly supported by Northern blot assays that revealed a significant reduction in the accumulation of transcripts corresponding to the 16∶0‐ACP thioesterase in germplasm homozygous for the fap nc allele. DA - 2001/4// PY - 2001/4// DO - 10.1007/s11746-001-0265-4 VL - 78 IS - 4 SP - 335-340 SN - 1558-9331 KW - developing-seed KW - fap-alleles KW - genetics KW - glycerolipid composition KW - Glycine max KW - metabolism KW - oil KW - palmitic acid KW - phospholipid KW - saturated fat ER - TY - JOUR TI - Infection with Bartonella weissii and Detection of Nanobacterium Antigens in a North Carolina Beef Herd AU - Breitschwerdt, E. B. AU - Sontakke, S. AU - Cannedy, A. AU - Hancock, S. I. AU - Bradley, J. M. T2 - Journal of Clinical Microbiology AB - Very recently, Bartonella organisms have been isolated from large ruminants (deer, elk, and dairy and beef cattle) located in the United States and in France. In this study, we report the serologic, microbiologic, and molecular findings related to the isolation of a Bartonella species in North Carolina beef cattle and the detection of nanobacterial antigen using a commercially available enzyme-linked immunosorbent assay. Between August 1998 and September 1999, blood was collected from 38 cattle ranging in age from 1 month to 6.5 years. After a 1-month incubation period, a Bartonella sp. was isolated on a 5% rabbit blood agar plate from three of six EDTA blood samples. PCR amplification of the 16S rRNA gene from all three isolates resulted in a DNA sequence that was 100% identical to that of B. weissii 16S rRNA (GenBank no. AF199502). By IFA testing, 36 of 38 cattle had antibodies (> or =1:64) to Bartonella weissii (bovine origin) antigens. Nanobacterial antigen was detected in 22 of 22 serum samples. We conclude that infection with an organism similar or closely related to B. weissii can occur in North Carolina cattle and that although their actual existence is still controversial Nanobacterium antigens were detected with a commercially available test kit. The epidemiology, vector biology, and potential pathogenicity of these organisms in cattle deserve future consideration. DA - 2001/3/1/ PY - 2001/3/1/ DO - 10.1128/JCM.39.3.879-882.2001 VL - 39 IS - 3 SP - 879-882 J2 - Journal of Clinical Microbiology LA - en OP - SN - 0095-1137 UR - http://dx.doi.org/10.1128/JCM.39.3.879-882.2001 DB - Crossref ER - TY - JOUR TI - Functional genomics of odor-guided behavior in Drosophila melanogaster AU - Anholt, RRH AU - Fanara, JJ AU - Fedorowicz, GM AU - Ganguly, I AU - Kulkarni, NH AU - Mackay, TFC AU - Rollmann, SM T2 - CHEMICAL SENSES AB - The avoidance response to repellent odorants in Drosophila melanogaster, a response essential for survival, provides an advantageous model for studies on the genetic architecture of olfactory behavior. Transposon tagging in a highly inbred strain of flies in combination with a rapid and simple statistical behavioral assay enables the identification of not only large phenotypic effects, but also small aberrations from wild-type avoidance behavior. The recent completion of the sequence of the Drosophila genome facilitates the molecular characterization of transposon-tagged genes and correlation between gene expression and behavior in smell-impaired (smi) mutant lines. Quantitative genetic analyses of a collection of smi lines in a co-isogenic background revealed an extensive network of epistatic interactions among genes that shape the olfactory avoidance response. Candidate genes for several of these transposon-tagged smi loci implicate genes that mediate odorant recognition, including a novel odorant binding protein; signal propagation, including a voltage-gated sodium channel; and a protein containing multiple leucine rich repeats and PDZ domains likely to be involved in postsynaptic organization in the olfactory pathway. Several novel genes of unknown function have also been implicated, including a novel tyrosine-regulated protein kinase. The discovery and characterization of novel gene products that have major, hitherto unappreciated effects on olfactory behavior will provide new insights in the generation and regulation of odor-guided behavior. The identification and functional characterization of proteins encoded by smi genes that form part of the olfactory subgenome and correlation of polymorphisms in these genes with variation in odor-guided behavior in natural populations will advance our understanding of the genetic architecture of chemosensory behavior. DA - 2001/2// PY - 2001/2// DO - 10.1093/chemse/26.2.215 VL - 26 IS - 2 SP - 215-221 SN - 0379-864X ER - TY - JOUR TI - Evaluation of the dystrophin-glycoprotein complex, alpha-actinin, dysferlin and calpain 3 in an autosomal recessive muscular dystrophy in Labrador retrievers AU - Olby, NJ AU - Sharp, NJH AU - Anderson, LVB AU - Kunkel, LM AU - Bonnemann, CG T2 - NEUROMUSCULAR DISORDERS AB - Labrador retrievers suffer from an autosomal recessive muscular dystrophy of unknown aetiology. Dogs affected with this disease develop generalized weakness associated with severe, generalized skeletal muscle atrophy and mild elevations in creatine kinase in the first few months of life. The severity of signs tends to progress over the first year of life but can vary from mild exercise intolerance to non-ambulatory tetraparesis. Beyond 1 year of age, the signs usually stabilize and although muscle mass does not increase, affected dogs' strength may improve slightly. The pathological changes present on muscle biopsy include marked variation in muscle fibre size with hypertrophied and round atrophied fibres present. There is an increased number of fibres with central nuclei and split fibres can be seen. It has been suggested that the disorder is a model for limb-girdle muscular dystrophy. In recent years, mutations in genes encoding the proteolytic enzyme, calpain 3, a novel protein named dysferlin, and components of the dystrophin-glycoprotein complex have been identified as causes of autosomal recessive limb-girdle muscular dystrophy. We have evaluated these proteins in normal dogs and in three Labrador retrievers with autosomal recessive muscular dystrophy using immunohistochemistry and Western blot analysis on frozen skeletal muscle. The results demonstrate that dystrophin, the sarcoglycans, alpha-actinin, dysferlin and calpain 3 are present in the normal and affected dogs. We conclude that this autosomal recessive muscular dystrophy is not due to a deficiency of alpha-actinin, or any of the known autosomal recessive limb-girdle muscular dystrophy proteins, although we cannot rule out a malfunction of any of these proteins. DA - 2001/1// PY - 2001/1// DO - 10.1016/S0960-8966(00)00166-8 VL - 11 IS - 1 SP - 41-49 SN - 0960-8966 KW - autosomal recessive muscular dystrophy in Labrador retrievers KW - limb-girdle muscular dystrophy KW - congenital muscular dystrophy KW - sarcoglycan KW - merosin KW - calpain 3 KW - dysferlin ER - TY - JOUR TI - Effect of alleles governing 16 : 0 concentration on glycerolipid composition in developing soybeans AU - Wilson, RF AU - Marquardt, TC AU - Novitzky, WP AU - Burton, JW AU - Wilcox, , JR AU - Dewey, RE T2 - JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY AB - Abstract Soybean [ Glycine max (L.) Merr.] oil typically contains 11% palmitic acid, but germplasm with recessive alleles at Fap gene loci exhibit from less than 4% to about 35% 16:0, Although these alleles are used to develop new cultivars, little is known about how they influence palmitic acid concentration. One theory suggests that fap alleles may mediate differences in triacylglycerol composition through genetic effects on the activity or substrate specificity of acyltransferases, such as diacylglycerol acyltransferase (EC 2.3.1.20). Based on logistic function analysis of developing seed, differences in fag allele expression are evident in the rate of palmitic acid accumulation in triacylglycerol, with peak deposition near mid‐seed fill. Acetate saturation kinetics also reveal a strong positive relation between the relative amount of de novo palmitic acid synthesis and the indigenous palmitic acid concentration in triacylglycerol among fap genotypes. However, no differences appear in the kinetics of palmitoyl‐CoA metabolism in developing seed of these genotypes. Therefore, the fap alleles apparently do not encode or regulate the activities of glycerolipid acyltransferase enzymes. Rather, major genetic effects on triacylglycerol composition accrue through regulation of palmitic acid production in the plastids of developing soybean cotyledons. DA - 2001/4// PY - 2001/4// DO - 10.1007/s11746-001-0264-5 VL - 78 IS - 4 SP - 329-334 SN - 1558-9331 KW - developing-seed KW - fap-alleles KW - genetics KW - glycerolipid composition KW - Glycine max KW - logistic function KW - metabolism KW - oil KW - palmitic acid KW - saturated fat ER - TY - JOUR TI - The genetic architecture of odor-guided behavior in Drosophila melanogaster AU - Anholt, RRH AU - Mackay, TFC T2 - BEHAVIOR GENETICS DA - 2001/1// PY - 2001/1// DO - 10.1023/A:1010201723966 VL - 31 IS - 1 SP - 17-27 SN - 0001-8244 KW - olfaction KW - chemoreception KW - quantitative genetics KW - P-element insertional mutagenesis KW - epistasis KW - functional genomics ER - TY - JOUR TI - Structure of linkage disequilibrium and phenotypic associations in the maize genome AU - Remington, DL AU - Thornsberry, JM AU - Matsuoka, Y AU - Wilson, LM AU - Whitt, , SR AU - Doeblay, J AU - Kresovich, S AU - Goodman, MM AU - Buckler, ES T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - Association studies based on linkage disequilibrium (LD) can provide high resolution for identifying genes that may contribute to phenotypic variation. We report patterns of local and genome-wide LD in 102 maize inbred lines representing much of the worldwide genetic diversity used in maize breeding, and address its implications for association studies in maize. In a survey of six genes, we found that intragenic LD generally declined rapidly with distance ( r 2 < 0.1 within 1500 bp), but rates of decline were highly variable among genes. This rapid decline probably reflects large effective population sizes in maize during its evolution and high levels of recombination within genes. A set of 47 simple sequence repeat (SSR) loci showed stronger evidence of genome-wide LD than did single-nucleotide polymorphisms (SNPs) in candidate genes. LD was greatly reduced but not eliminated by grouping lines into three empirically determined subpopulations. SSR data also supplied evidence that divergent artificial selection on flowering time may have played a role in generating population structure. Provided the effects of population structure are effectively controlled, this research suggests that association studies show great promise for identifying the genetic basis of important traits in maize with very high resolution. DA - 2001/9/25/ PY - 2001/9/25/ DO - 10.1073/pnas.201394398 VL - 98 IS - 20 SP - 11479-11484 SN - 0027-8424 ER - TY - JOUR TI - Silencing of a meristematic gene using geminivirus-derived vectors AU - Peele, C AU - Jordan, CV AU - Muangsan, N AU - Turnage, M AU - Egelkrout, E AU - Eagle, P AU - Hanley-Bowdoin, L AU - Robertson, D T2 - PLANT JOURNAL AB - Geminiviruses are DNA viruses that replicate and transcribe their genes in plant nuclei. They are ideal vectors for understanding plant gene function because of their ability to cause systemic silencing in new growth and ease of inoculation. We previously demonstrated DNA episome-mediated gene silencing from a bipartite geminivirus in Nicotiana benthamiana. Using an improved vector, we now show that extensive silencing of endogenous genes can be obtained using less than 100 bp of homologous sequence. Concomitant symptom development varied depending upon the target gene and insert size, with larger inserts producing milder symptoms. In situ hybridization of silenced tissue in attenuated infections demonstrated that silencing occurs in cells that lack detectable levels of viral DNA. A mutation confining the virus to vascular tissue produced extensive silencing in mesophyll tissue, further demonstrating that endogenous gene silencing can be separated from viral infection. We also show that two essential genes encoding a subunit of magnesium chelatase and proliferating cell nuclear antigen (PCNA) can be silenced simultaneously from different components of the same viral vector. Immunolocalization of silenced tissue showed that the PCNA protein was down-regulated throughout meristematic tissues. Our results demonstrate that geminivirus-derived vectors can be used to study genes involved in meristem function in intact plants. DA - 2001/8// PY - 2001/8// DO - 10.1046/j.1365-313x.2001.01080.x VL - 27 IS - 4 SP - 357-366 SN - 0960-7412 KW - Geminiviruses KW - homology-dependent gene silencing KW - meristems KW - functional genomics KW - plant DNA viruses KW - magnesium chelatase KW - proliferating cell nuclear antigen ER - TY - JOUR TI - Serologic and molecular evidence of coinfection with multiple vector-borne pathogens in dogs from Thailand AU - Suksawat, J AU - Yu, XJ AU - Hancock, SI AU - Hegarty, BC AU - Nilkumhang, P AU - Breitschwerdt, EB T2 - JOURNAL OF VETERINARY INTERNAL MEDICINE AB - Forty-nine dogs from Thailand were evaluated for serologic evidence of exposure or polymerase chain reaction (PCR) evidence of infection with vectorborne pathogens, including Ehrlichia sp. (Ehrlichia canis, Ehrlichia chaffeensis, Ehrlichia equi, and Ehrlichia risticii), Bartonella vinsonii subsp. berkhoffi (Bvb), spotted fever group (SFG) rickettsiae (Rickettsia rickettsii), Typhus group (TG) rickettsiae (Rickettsia canada, Rickettsia prowazekii, and Rickettsia typhi), and Babesia sp. (Babesia canis and Babesia gibsonii). All study dogs had at least 1 of 3 entry criteria: fever, anemia, or thrombocytopenia. By immunofluorescence antibody (IFA) testing, seroreactivity was most prevalent to E chaffeensis (74%) and E canis (71%) antigens, followed by E equi (58%), Bvb (38%), E risticii (38%), R prowazekii (24%), B canis (20%), R rickettsii (12%), R canada (4%), and B gibsonii (4%) antigens. There was 100% concordance between E canis IFA and Western blot immunoassay (WI) for 35 of 35 samples; 2 samples were IFA and WI reactive only to E equi antigens. By PCR amplification, 10 dogs were found to be infected with E canis, 5 with Ehrlichia platys, and 3 with B canis. Sequencing of PCR products was undertaken to compare Ehrlichia strains from Thailand to strains originating from the United States. Partial DNA sequence analysis confirmed infection with E canis and E platys, with identical 16S rRNA sequence alignment to E canis (U26740) and to E platys (M83801), as reported in GenBank. Partial E canis P28.1 and P28.2 amino acid sequences from Thai dogs were divergent from analogous sequences derived from North American E canis (AF082744) strains, suggesting that the Thai dogs were infected with a geographically distinct strain of E canis compared to North American strains. The results of this study indicate that dogs in Thailand have substantial exposure to vectorborne diseases and that coinfection with these pathogens may be common. DA - 2001/// PY - 2001/// DO - 10.1892/0891-6640(2001)015<0453:SAMEOC>2.3.CO;2 VL - 15 IS - 5 SP - 453-462 SN - 1939-1676 KW - canine KW - diseases KW - polymerase chain reaction KW - serology KW - ticks ER - TY - JOUR TI - Resistance to mefenoxam and metalaxyl among field isolates of Phytophthora capsici causing Phytophthora blight of bell pepper AU - Parra, G AU - Ristaino, JB T2 - PLANT DISEASE AB - Incidence of Phytophthora blight in bell pepper fields that were sprayed for the first time with Ridomil Gold (mefenoxam) according to labeled recommendations was higher in North Carolina in 1997 than in previous years. Mefenoxam is the more active enantiomer contained in the racemic fungicide metalaxyl. A total of 150 isolates were obtained from 17 fields at eight grower locations. Among isolates from all locations, 30% were classified as sensitive, 10% as intermediate, and 59% were resistant to mefenoxam. Mefenoxam-resistant isolates were found in 82% of the fields sampled (14 of 17 fields). The proportion of resistant isolates in individual (fields ranged from 28 to 100%. The mean effective concentration (EC50) values for mefenoxam-sensitive isolates was 0.568 μg ml-1 (ranging from 0.12 to 1.1 μg ml-1), whereas the mean EC50 value for mefenoxam-resistant isolates was 366.5 μg ml-1 (ranging from 3 to 863 μg ml-1). The mean EC50 value for metalaxyl-sensitive isolates was 0.27 μg ml-1 (ranging from 0.00002 to 1.3 μg ml-1) and for metalaxyl-resistant isolates was 470.34 μg ml-1 (ranging from 10 to 966 μg ml-1). The greatest proportion of resistant isolates came from fields where mefenoxam was used alone rather than in combination with other fungicides. Both mating types were found among resistant isolates, suggesting that these isolates may persist in soil in subsequent years. Field isolates of Phytophthora capsici resistant to mefenoxam on pepper have not been reported previously and now pose new challenges for management of this important disease. DA - 2001/10// PY - 2001/10// DO - 10.1094/PDIS.2001.85.10.1069 VL - 85 IS - 10 SP - 1069-1075 SN - 0191-2917 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034813367&partnerID=MN8TOARS KW - epidemiology KW - fungicide resistance KW - fungicide sensitivity KW - Phytophthora root and crown rot ER - TY - JOUR TI - Plasma membrane phosphatidylinositol 4,5-bisphosphate levels decrease with time in culture AU - Heilmann, I AU - Perera, IY AU - Gross, W AU - Boss, WF T2 - PLANT PHYSIOLOGY AB - During the stationary phase of growth, after 7 to 12 d in culture, the levels of phosphatidylinositol 4,5-bisphosphate (PtdInsP(2)) decreased by 75% in plasma membranes of the red alga Galdieria sulphuraria. Concomitant with the decrease in PtdInsP(2) levels in plasma membranes, there was an increase in PtdInsP(2) in microsomes, suggesting that the levels of plasma membrane PtdInsP(2) are regulated differentially. The decline of PtdInsP(2) in plasma membranes was accompanied by a 70% decrease in the specific activity of PtdInsP kinase and by reduced levels of protein cross-reacting with antisera against a conserved PtdInsP kinase domain. Upon osmotic stimulation, the loss of PtdInsP(2)from the plasma membrane increased from 10% in 7-d-old cells to 60% in 12-d-old cells, although the levels of inositol 1,4,5-trisphosphate (InsP(3)) produced in whole cells were roughly equal at both times. When cells with low plasma membrane PtdInsP(2) levels were osmotically stimulated, a mild osmotic stress (12.5 mM KCl) activated PtdInsP kinase prior to InsP(3) production, whereas in cells with high plasma membrane PtdInsP(2), more severe stress (250 mM KCl) was required to induce an increase in PtdInsP kinase activity. The differential regulation of a plasma membrane signaling pool of PtdInsP(2) is discussed with regard to the implications for understanding the responsive state of cells. DA - 2001/8// PY - 2001/8// DO - 10.1104/pp.126.4.1507 VL - 126 IS - 4 SP - 1507-1518 SN - 1532-2548 ER - TY - JOUR TI - Overlapping plant signal transduction pathways induced by a parasitic nematode and a rhizobial endosymbiont AU - Koltai, H AU - Dhandaydham, M AU - Opperman, C AU - Thomas, J AU - Bird, D T2 - MOLECULAR PLANT-MICROBE INTERACTIONS AB - Root-knot nematodes and rhizobia establish interactions with roots characterized by the de novo induction of host structures, termed giant cells and nodules, respectively. Two transcription regulators, PHAN and KNOX, required for the establishment of meristems were previously shown to be expressed in tomato giant cells. We isolated the orthologues of PHAN and KNOX (Mt-phan and Mt-knox-1) from the model legume Medicago truncatula, and established the spatial distribution of their expression in situ. We confirmed that Mt-phan and Mt-knox-1 are expressed in lateral root initials and in nematode-induced giant cells and showed that they are expressed in nodules induced by Sinorhizobium meliloti. Expression of both genes becomes spatially restricted as the nodules develop. We further examined nematode feeding sites for the expression of two genes involved in nodule formation, ccs52 (encodes a mitotic inhibitor) and ENOD40 (encodes an early, nodulation mitogen), and found transcripts of both genes to be present in and around giant cells induced in Medicago. Collectively, these results reveal common elements of host responses to mutualistic and parasitic plant endosymbionts and imply that overlapping regulatory pathways lead to giant cells and nodules. We discuss these pathways in the context of phytohormones and parallels between beneficial symbiosis and disease. DA - 2001/10// PY - 2001/10// DO - 10.1094/MPMI.2001.14.10.1168 VL - 14 IS - 10 SP - 1168-1177 SN - 0894-0282 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0034800333&partnerID=MN8TOARS KW - cytokinin KW - Meloidogyne incognita KW - Nod factor KW - PHANTASTICA KW - polar auxin flow KW - rough sheath2 ER - TY - JOUR TI - New insight into RNase P RNA structure from comparative analysis of the archaeal RNA AU - Harris, JK AU - Haas, ES AU - Williams, D AU - Frank, DN AU - Brown, JW T2 - RNA AB - A detailed comparative analysis of archaeal RNase P RNA structure and a comparison of the resulting structural information with that of the bacterial RNA reveals that the archaeal RNase P RNAs are strikingly similar to those of Bacteria. The differences between the secondary structure models of archaeal and bacterial RNase P RNA have largely disappeared, and even variation in the sequence and structure of the RNAs are similar in extent and type. The structure of the cruciform (P7–11) has been reevaluated on the basis of a total of 321 bacterial and archaeal sequences, leading to a model for the structure of this region of the RNA that includes an extension to P11 that consistently organizes the cruciform and adjacent highly-conserved sequences. DA - 2001/2// PY - 2001/2// DO - 10.1017/S1355838201001777 VL - 7 IS - 2 SP - 220-232 SN - 1469-9001 KW - Archaea KW - archaebacteria KW - ribonuclease P KW - ribozyme KW - rnpB ER - TY - JOUR TI - Map-based cloning of quantitative trait loci: progress and prospects AU - Remington, D. L. AU - Ungerer, M. C. AU - Purugganan, M. D. T2 - Genetical Research DA - 2001/// PY - 2001/// VL - 78 IS - 3 SP - 213-218 ER - TY - JOUR TI - Investigation of rational syntheses of heteroleptic porphyrinic lanthanide (europium, cerium) triple-decker sandwich complexes AU - Gross, T AU - Chevalier, F AU - Lindsey, JS T2 - INORGANIC CHEMISTRY AB - The use of lanthanide triple-decker sandwich molecules containing porphyrins and phthalocyanines in molecular information storage applications requires the ability to attach monomeric triple deckers or arrays of triple deckers to electroactive surfaces. Such applications are limited by existing methods for preparing triple deckers. The reaction of a lanthanide porphyrin half-sandwich complex ((Por)M(acac)) with a dilithium phthalocyanine (PcLi2) in refluxing 1,2,4-trichlorobenzene (bp 214 degrees C) affords a mixture of triple deckers of composition (Pc)M(Pc)M(Por), (Por)M(Pc)M(Por), and (Pc)M(Por)M(Pc). We have investigated more directed methods for preparing triple deckers of a given type with distinct metals in each layer. Application of the method of Weiss, which employs reaction of a (Por)M(acac) species with a lanthanide double decker in refluxing 1,2,4-trichlorobenzene, afforded the desired triple decker in some cases but a mixture of triple deckers in others. The approach we developed employs in situ formation of the lanthanide reagent EuCl[N(SiMe3)2]2 or CeI[N(SiMe3)2]2, which upon reaction with a porphyrin affords the half-sandwich complex (Por)EuX or (Por)CeX' (X = Cl, N(SiMe3)2; X' = I, N(SiMe3)2). Subsequent reaction with PcLi2 gives the double decker (Por)M(Pc). The (Por(1))EuX half-sandwich complex gave the desired triple decker upon reaction with (Pc)Eu(Pc) but little of the desired product upon reaction with (Por(2))Eu(Pc). The (Por(1))CeX' half-sandwich complex reacted with europium double deckers (e.g., (tBPc)Eu(Por(2)), (tBPc)2Eu) to give the triple deckers (Por(1))Ce(tBPc)Eu(Por(2)) and (Por(1))Ce(tBPc)Eu(tBPc) in a rational manner (tB = tetra-tert-butyl). The reactions yielding the half-sandwich, double-decker, and triple-decker complexes were performed in refluxing bis(2-methoxyethyl) ether (bp 162 degrees C). The porphyrins incorporated in the various triple deckers include meso-tetrapentylporphyrin, meso-tetra-p-tolylporphyrin, octaethylporphyrin, and meso-tetraarylporphyrins bearing iodo, ethynyl, or iodo and ethynyl substituents. The triple deckers bearing iodo and/or ethynyl substituents constitute useful building blocks for information storage applications. DA - 2001/8/27/ PY - 2001/8/27/ DO - 10.1021/ic0101634 VL - 40 IS - 18 SP - 4762-4774 SN - 0020-1669 ER - TY - JOUR TI - In vitro reactivation of Ancylostoma caninum tissue-arrested third-stage larvae by transforming growth factor-beta AU - Arasu, P T2 - JOURNAL OF PARASITOLOGY AB - Developmental arrest in Ancylostoma caninum is associated with preparasitic, free-living third-stage (L3) larvae, as well as anthelmintic-resilient hypobiotic L3 larvae within the tissues of an infected dog. With the tissue-arrested larvae, pregnancy and, more specifically, the hormonal effects of estrogen and prolactin mediate reactivation resulting in transmammary transmission of infection to nursing puppies. Estrogen and prolactin have been shown to be critically involved in upregulation of transforming growth factor (TGF)-beta2 during pregnancy, and studies on the soil nematode Caenorhabditis elegans further implicate TGF-beta and insulin-like signaling pathways with larval arrest and reactivation. In this report, an in vitro assay was used to show that neither estrogen, prolactin, nor insulin had a direct effect on the feeding/reactivation response of tissue-arrested larvae; however, TGF-beta isoforms 1 and 2 both had significant stimulatory effects that were comparable to the effects of dog serum. The stimulatory effects of serum could be blocked by preincubation with anti-TGF-beta antibodies. Taken together, the results support the hypothesis that during pregnancy, host-derived TGF-beta can signal a parasite-encoded receptor to trigger the reactivation of tissue-arrested larvae. TGF-beta had no effect on preparasitic larvae, suggesting that different signals may be involved in reactivation of the 2 different arrested forms of A. caninum L3 larvae. DA - 2001/8// PY - 2001/8// DO - 10.1645/0022-3395(2001)087[0733:IVROAC]2.0.CO;2 VL - 87 IS - 4 SP - 733-738 SN - 0022-3395 ER - TY - JOUR TI - Hyperosmotic stress induces the rapid phosphorylation of a soybean phosphatidylinositol transfer protein homolog through activation of the protein kinases SPK1 and SPK2 AU - Monks, DE AU - Aghoram, K AU - Courtney, PD AU - DeWald, DB AU - Dewey, RE T2 - PLANT CELL AB - Although phosphatidylinositol transfer proteins (PITPs) are known to serve critical functions in regulating a varied array of signal transduction processes in animals and yeast, the discovery of a similar class of proteins in plants occurred only recently. Here, we report the participation of Ssh1p, a soybean PITP-like protein, in the early events of osmosensory signal transduction in plants, a function not attributed previously to animal or yeast PITPs. Exposure of plant tissues to hyperosmotic stress led to the rapid phosphorylation of Ssh1p, a modification that decreased its ability to associate with membranes. An osmotic stress-activated Ssh1p kinase activity was detected in several plant species by presenting recombinant Ssh1p as a substrate in in-gel kinase assays. Elements of a similar osmosensory signaling pathway also were conserved in yeast, an observation that facilitated the identification of soybean protein kinases SPK1 and SPK2 as stress-activated Ssh1p kinases. This study reveals the activation of SPK1 and/or SPK2 and the subsequent phosphorylation of Ssh1p as two early successive events in a hyperosmotic stress-induced signaling cascade in plants. Furthermore, Ssh1p is shown to enhance the activities of a plant phosphatidylinositol 3-kinase and phosphatidylinositol 4-kinase, an observation that suggests that the ultimate function of Ssh1p in cellular signaling is to alter the plant's capacity to synthesize phosphoinositides during periods of hyperosmotic stress. DA - 2001/5// PY - 2001/5// DO - 10.1105/tpc.13.5.1205 VL - 13 IS - 5 SP - 1205-1219 SN - 1532-298X ER - TY - PAT TI - High-density non-volatile memory devices incorporating thiol-derivatized porphyrin trimers AU - Clausen, P. C. AU - Lindsey, J. S. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Genotypic control of high-frequency adventitious shoot regeneration via somatic organogenesis in loblolly pine AU - Tang, W AU - Whetten, R AU - Sederoff, R T2 - PLANT SCIENCE AB - Mature zygotic embryos of 24 genotypes of loblolly pine (Pinus taeda L.) were used as explants to establish an adventitious shoot regeneration system through somatic organogenesis. Callus formation frequencies of 18.2 (genotype 11-1103) -77.7% (genotype 7-100) have been induced from mature zygotic embryos of all genotypes tested on callus induction medium (basal salts) containing 2,4-dichlorophenoxyacetic acid (2,4-D) or alpha-naphthaleneacetic acid (NAA), 6-benzyladenine (BA), and kinetin. Adventitious shoot regeneration via organogenesis with the frequency of 5.4 (genotype 11-1103 and 7-2) -77.2% (genotype 8-1082) was obtained from callus and tissue cultures derived from mature zygotic embryos of 24 genotypes of loblolly pine. The highest mean number of 18 adventitious buds per piece of callus 0.5x0.5 cm(2) in size was obtained from genotype 8-1082. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg/l indole-3-butyric acid (IBA) and 1 mg/l BA. After rooting, regenerated plantlets were established in soil. These results suggested that adventitious shoot regeneration via somatic organogenesis was influenced by the genotypes. The in vitro regeneration procedure established in this investigation could be used for clonal micropropagation of some genotypes of loblolly pine, as well as for establishing a transformation system in coniferous species. DA - 2001/7// PY - 2001/7// DO - 10.1016/S0168-9452(01)00394-6 VL - 161 IS - 2 SP - 267-272 SN - 0168-9452 KW - Pinus taedu L. KW - organogenesis KW - adventitious shoot regeneration KW - callus induction frequency KW - differentiation frequency ER - TY - JOUR TI - Dimeric procaspase-3 unfolds via a four-state equilibrium process AU - Bose, K AU - Clark, AC T2 - BIOCHEMISTRY AB - We have examined the folding and assembly of a catalytically inactive mutant of procaspase-3, a homodimeric protein that belongs to the caspase family of proteases. The caspase family, and especially caspase-3, is integral to apoptosis. The equilibrium unfolding data demonstrate a plateau between 3 and 5 M urea, consistent with an apparent three-state unfolding process. However, the midpoint of the second transition as well as the amplitude of the plateau are dependent on the protein concentration. Overall, the data are well described by a four-state equilibrium model in which the native dimer undergoes an isomeration to a dimeric intermediate, and the dimeric intermediate dissociates to a monomeric intermediate, which then unfolds. By fitting the four-state model to the experimental data, we have determined the free energy change for the first step of unfolding to be 8.3 +/- 1.3 kcal/mol. The free energy change for the dissociation of the dimeric folding intermediate to two monomeric intermediates is 10.5 +/- 1 kcal/mol. The third step in the unfolding mechanism represents the complete unfolding of the monomeric intermediate, with a free energy change of 7.0 +/- 0.5 kcal/mol. These results show two important points. First, dimerization of procaspase-3 occurs as a result of the association of two monomeric folding intermediates, demonstrating that procaspase-3 dimerization is a folding event. Second, the stability of the dimer contributes significantly to the conformational free energy of the protein (18.8 of 25.8 kcal/mol). DA - 2001/11/27/ PY - 2001/11/27/ DO - 10.1021/bi0110387 VL - 40 IS - 47 SP - 14236-14242 SN - 0006-2960 ER - TY - JOUR TI - Differentiation of Ehrlichia platys and E. equi Infections in Dogs by Using 16S Ribosomal DNA-Based PCR AU - Hancock, S. I. AU - Breitschwerdt, E. B. AU - Pitulle, C. T2 - Journal of Clinical Microbiology AB - We have encountered a previously unrecognized specificity problem when using the small-subunit ribosomal DNA (16S rDNA)-based PCR primers recommended for use in the identification of Ehrlichia equi in clinical samples. These PCR primers annealed to E. platys 16S rDNA in blood samples containing high levels of E. platys organisms. Therefore, we designed and tested new PCR primers for the identification of E. equi. DA - 2001/12/1/ PY - 2001/12/1/ DO - 10.1128/JCM.39.12.4577-4578.2001 VL - 39 IS - 12 SP - 4577-4578 J2 - Journal of Clinical Microbiology LA - en OP - SN - 0095-1137 UR - http://dx.doi.org/10.1128/JCM.39.12.4577-4578.2001 DB - Crossref ER - TY - JOUR TI - An analysis of polygenes affecting wing shape on chromosome 2 in Drosophila melanogaster AU - Weber, K. AU - Eisman, R. AU - Higgins, S. AU - Morey, L. AU - Patty, A. AU - Tausek, M. AU - Zeng, Z. B. T2 - Genetics DA - 2001/// PY - 2001/// VL - 159 IS - 3 SP - 1045-1057 ER - TY - JOUR TI - A general polyploid model for analyzing gene segregation in outcrossing tetraploid species AU - Wu, R. L. AU - Gallo-Meagher, M. AU - Littell, R. C. AU - Zeng, Z. B. T2 - Genetics DA - 2001/// PY - 2001/// VL - 159 IS - 2 SP - 869-882 ER - TY - JOUR TI - Synthesis and excited-state photodynamics of perylene-porphyrin dyads. 1. Parallel energy and charge transfer via a diphenylethyne linker AU - Prathapan, S AU - Yang, SI AU - Seth, J AU - Miller, MA AU - Bocian, DF AU - Holten, D AU - Lindsey, JS T2 - JOURNAL OF PHYSICAL CHEMISTRY B AB - The photophysical properties of a perylene−porphyrin dyad have been examined with the aim of using this construct for molecular photonics applications. The dyad consists of a perylene-bis(imide) dye (PDI) connected to a zinc porphyrin (Zn) via a diphenylethyne linker (pep). In both polar and nonpolar solvents, the photoexcited perylene unit (PDI*) decays very rapidly (lifetimes of 2.5 (toluene) and 2.4 ps (acetonitrile)) by energy transfer to the porphyrin, forming PDI−pep−Zn* in high yield (80%, toluene; 70% acetonitrile), and hole transfer to the porphyrin, forming PDI-−pep−Zn+ in lesser yield (20%, toluene; 30% acetonitrile). In both toluene and acetonitrile, the Zn* excited state subsequently decays with a lifetime of 0.4 ns primarily (80%) by electron transfer to the perylene (forming PDI-−pep−Zn+). In the nonpolar solvent (toluene), the PDI-−pep−Zn+ charge-transfer product has a lifetime of >10 ns and decays by charge recombination primarily to the ground state but also by thermal repopulation of the Zn* excited state. The occurrence of the latter process provides a direct experimental measure of the energy of the charge-separated state. In the polar solvent (acetonitrile), the PDI-−pep−Zn+ charge-separated state decays much more rapidly (<0.5 ns) and exclusively to the ground state. In general, the complementary perylene and porphyrin absorption properties together with very fast and efficient PDI*−pep−Zn → PDI−pep−Zn* energy transfer suggest that perylenes have significant potential as accessory pigments in porphyrin-based arrays for light-harvesting and energy-transport applications. Furthermore, the finding of fast energy transfer initiated in PDI*, charge-transfer reactions that can be elicited either in PDI* or Zn*, and a charge-separated state (PDI-−pep−Zn+) that can be long- or short-lived depending on solvent polarity, indicates the versatility of the perylene−porphyrin motif for a variety of applications in molecular photonics. DA - 2001/8/30/ PY - 2001/8/30/ DO - 10.1021/jp010335i VL - 105 IS - 34 SP - 8237-8248 SN - 1089-5647 ER - TY - JOUR TI - Synthesis and excited-state photodynamics in perylene-porphyrin dyads 2. Effects of porphyrin metalation state on the energy-transfer, charge-transfer, and deactivation channels AU - Yang, SI AU - Prathapan, S AU - Miller, MA AU - Seth, J AU - Bocian, DF AU - Lindsey, JS AU - Holten, D T2 - JOURNAL OF PHYSICAL CHEMISTRY B AB - The photophysical properties of two perylene−porphyrin dyads have been examined in detail with the aim of expanding the functional utility of these constructs for molecular optoelectronics applications. The dyads consist of a perylene-bis(imide) dye (PDI) connected to either a magnesium porphyrin (Mg) or a free base porphyrin (Fb) via a diphenylethyne (pep) linker. The photophysical behavior of these two dyads show both similarities and differences to one another and to the dyad containing a zinc porphyrin (Zn) that was examined in the previous paper in this series. In the case of both PDI−pep−Fb and PDI−pep−Mg in toluene, the excited perylene unit (PDI*) decays rapidly (Fb = 2.9 ps; Mg = 2.5 ps) by energy transfer to the porphyrin forming PDI−pep−Por* in relatively high yield (Fb ∼ 85%; Mg ∼ 50%) and hole transfer to the porphyrin forming PDI-−pep−Por+ (Fb ∼ 15%; Mg ∼ 50%). This behavior parallels that observed for PDI−pep−Zn, for which rapid (2.5 ps) decay of PDI* affords PDI−pep−Zn* and PDI-−pep−Por+ with yields of 80% and 20%, respectively. The subsequent behavior of the Fb-containing dyad is distinctly different in two ways from that of the Zn or Mg porphyrin-containing dyads. (1) Charge recombination within PDI-−pep−Fb+ primarily forms PDI−pep−Fb*, thereby complementing the formation of the latter species from PDI*−pep−Fb. (2) PDI−pep−Fb* subsequently decays to the ground state via fluorescence emission with a rate and yield that are nearly identical to those of an isolated Fb porphyrin. In contrast, for both PDI−pep−Mg and PDI−pep−Zn, the predominant decay process for PDI−pep−Por* is electron-transfer yielding PDI-−pep−Por+ (Zn ∼ 80%; Mg >99%). The rapid electron-transfer quenching of PDI−pep−Por* and the nonemissive character of PDI-−pep−Por+ leads to negligible fluorescence from the two metalloporphyrin-containing dyads after photoexcitation. The PDI-−pep−Por+ charge-separated product with Por = Mg or Zn is very long-lived (>10 ns) in toluene but decays much more rapidly (<0.5 ns) in acetonitrile. The differences in the rates of the various charge-transfer and charge-recombination processes of all of the dyads are consistent with a rate versus free-energy-gap profile (based on the relative redox potentials of the porphyrin constituents) that is in qualitative accord with electron-transfer theory. Collectively, the studies reported in this and the previous paper indicate that PDI−pep−Fb has the greatest potential utility in photonics applications wherein light harvesting by an accessory pigment, energy transport to an output chromophore, and emission (or energy transfer to another chromophore) are desired. On the other hand, PDI−pep−Mg (like PDI−pep−Zn) would be most useful as an all-optical gating element in which excited-state energy in an appended chromophore chain can be quenched by the charge-separated state of the perylene-porphyrin dyad, thereby shunting the light output or flow of energy. DA - 2001/8/30/ PY - 2001/8/30/ DO - 10.1021/jp010336a VL - 105 IS - 34 SP - 8249-8258 SN - 1089-5647 ER - TY - JOUR TI - Susceptibility of parent and interspecific F1 hybrid pine trees to tip moth damage in a coastal North Carolina planting AU - Highsmith, MT AU - Frampton, J AU - D O'Malley, AU - Richmond, J AU - Webb, M T2 - CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE DA - 2001/5// PY - 2001/5// DO - 10.1139/cjfr-31-5-919 VL - 31 IS - 5 SP - 919-923 SN - 0045-5067 ER - TY - JOUR TI - Risk factors for development of status epilepticus in dogs with idiopathic epilepsy and effects of status epilepticus on outcome and survival time: 32 cases (1990-1996) AU - Saito, M AU - Munana, KR AU - Sharp, NJH AU - Olby, NJ T2 - JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION AB - To identify risk factors for episodes of status epilepticus (SE) in dogs with idiopathic epilepsy and determine how SE affects long-term outcome and survival time.Retrospective study.32 dogs with idiopathic epilepsy.Information on signalment, seizure onset, initiation of treatment, anticonvulsants administered, number of episodes of SE, overall seizure control, and long-term outcome was obtained from medical records and through telephone interviews. Differences between dogs that did and did not have episodes of SE were evaluated statistically.19 (59%) dogs had 1 or more episodes of SE. Body weight was the only variable significantly different between dogs that did and did not have episodes of SE. Thirteen dogs (9 that did not have episodes of SE and 4 that did) were still alive at the time of the study and were > or = 10 years old. Six of the 19 (32%) dogs that had episodes of SE died of causes directly attributed to the seizure disorder. Mean life spans of dogs that did and did not have episodes of SE were 8.3 and 11.3 years, respectively. Survival time was significantly different between groups.Results suggest that a substantial percentage of dogs with idiopathic epilepsy will have episodes of SE. Dogs with greater body weights were more likely to have episodes of SE, and early appropriate seizure treatment did not appear to decrease the risk that dogs would have episodes. Most dogs with idiopathic epilepsy had an expected life span, but survival time was shorter for dogs that had episodes of SE. DA - 2001/9/1/ PY - 2001/9/1/ DO - 10.2460/javma.2001.219.618 VL - 219 IS - 5 SP - 618-623 ER - TY - JOUR TI - Protein kinase C-alpha coordinately regulates cytosolic phospholipase A(2) activity and the expression of cyclooxygenase-2 through different mechanisms in mouse keratinocytes AU - Wang, HQ AU - Kim, MP AU - Tiano, HF AU - Langenbach, R AU - Smart, RC T2 - MOLECULAR PHARMACOLOGY AB - Transgenic mice (K5-PKCα) in which the keratin 5 promoter directs the expression of protein kinase C-α (PKCα) to epidermal keratinocytes display a 10-fold increase in PKCα protein in their epidermis and alterations in phorbol ester-induced cutaneous inflammation [J Cell Science 1999;112:3497–3506]. In the current study, we have used these K5-PKCα mice to examine the role of PKCα in keratinocyte phospholipid metabolism/eicosanoid production and cutaneous inflammation. Primary keratinocytes from wild-type and transgenic mice were prelabeled in culture with [3H]arachidonic acid (AA) and subsequently treated with TPA. Compared with wild-type keratinocytes, K5-PKCα keratinocytes displayed a 2-fold increase in AA release. TPA treatment resulted in the phosphorylation of cPLA2. PKC inhibitors GF-109203X or H7, but not mitogen-activated protein/extracellular signal-regulated protein kinase (MEK) inhibitor PD 98059, could inhibit phosphorylation and AA release. Topical 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment of K5-PKCα mice resulted in a 5-fold increase in epidermal COX-2 induction and a 2- to 3-fold increase in prostaglandin (PG) E2 levels above that observed in TPA-treated wild-type mice. PD 98059, GF-109203X, or H7 could block cyclooxygenase-2 (COX-2) induction by TPA. Because C/EBPβ, a basic leucine zipper transcription factor, can be activated via a PKCα/mitogen-activated protein kinase pathway and can influence COX-2 expression, we examined whether C/EBPβ is involved in TPA-induced epidermal COX-2 expression. TPA-induced COX-2 expression was similar in C/EBPβ nullizygous and wild-type mice. In summary, our results indicate that epidermal PKCα coordinately regulates cPLA2 activity and COX-2 expression resulting in increased levels of AA and PGE2. Furthermore, PKCα-induced AA release and cPLA2phosphorylation are independent of MEK, whereas PKCα-induced COX-2 expression and PGE2 production are MEK-dependent and C/EBPβ-independent events. DA - 2001/4// PY - 2001/4// DO - 10.1124/mol.59.4.860 VL - 59 IS - 4 SP - 860-866 SN - 0026-895X ER - TY - JOUR TI - Predictors of outcome after dorsal decompressive laminectomy for degenerative lumbosacral stenosis in dogs: 69 cases (1987-1997) AU - De Risio, L AU - Sharp, NJH AU - Olby, NJ AU - Munana, KR AU - Thomas, WB T2 - JOURNAL OF THE AMERICAN VETERINARY MEDICAL ASSOCIATION AB - Abstract Objective —To identify predictive factors of long-term outcome after dorsal decompressive laminectomy for the treatment of degenerative lumbosacral stenosis (DLSS) in dogs. Design —Retrospective study. Sample Population —69 client-owned dogs. Procedure —Medical records of dogs that had undergone dorsal laminectomy at North Carolina State University and the University of Tennessee between 1987 and 1997 were reviewed. Dogs with diskospondylitis, traumatic lesions, or neoplasia of the lumbosacral region were excluded. All dogs had evidence of cauda equina compression on myelography, epidurography, computed tomography, or magnetic resonance imaging, along with subsequent confirmation of the lesion at surgery. Follow-up was performed by telephone inquiries to the referring veterinarian, the owner, or both, using a detailed questionnaire. Results —The outcome was excellent or good in 54 of 69 (78%) dogs over a mean follow-up period of 38 ± 22 months. Five of these 54 dogs had been incontinent for a median of 2 weeks prior to surgery. Six of the 15 dogs with a poor outcome had been incontinent for a median of 8 weeks before surgery. A significant correlation was detected between the presence of urinary and fecal incontinence prior to surgery and outcome. When duration of signs was considered, urinary incontinence was the only variable that significantly affected outcome. Conclusions and Clinical Relevance —Decompressive laminectomy is an effective treatment for DLSS, although dogs with urinary or fecal incontinence have a worse prognosis than dogs that are continent before surgery. Chronic urinary incontinence is a predictor of poor outcome for dogs with DLSS. ( J Am Vet Med Assoc 2001;219:624–628) DA - 2001/9/1/ PY - 2001/9/1/ DO - 10.2460/javma.2001.219.624 VL - 219 IS - 5 SP - 624-628 ER - TY - JOUR TI - PCR amplification of the Irish potato famine pathogen from historic specimens AU - Ristaino, JB AU - Groves, CT AU - Parra, GR T2 - NATURE DA - 2001/6// PY - 2001/6// DO - 10.1038/35079606 VL - 411 IS - 6838 SP - 695-697 SN - 1476-4687 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0035822055&partnerID=MN8TOARS ER - TY - JOUR TI - Integration of light and brassinosteroid signals in etiolated seedling growth AU - Clouse, SD T2 - TRENDS IN PLANT SCIENCE AB -

Abstract

Light and brassinosteroids are involved in the regulation of stem elongation in etiolated seedlings, but the molecular mechanism of their integration is not clear. Recent work in pea has shown that the dark-inducible, light-repressible small G protein, Pra2, interacts with and activates a cytochrome P450 C-2 hydroxylase involved in brassinolide biosynthesis. Thus, a novel link between light signal transduction and the endogenous levels of an important growth-promoting plant hormone has been established. DA - 2001/10// PY - 2001/10// DO - 10.1016/S1360-1385(01)02102-1 VL - 6 IS - 10 SP - 443-445 SN - 1360-1385 ER - TY - JOUR TI - High-throughput AFLP analysis using infrared dye-labeled primers and an automated DNA sequencer AU - Myburg, AA AU - Remington, DL AU - DM O'Malley, AU - Sederoff, RR AU - Whetten, RW T2 - BIOTECHNIQUES AB - Amplified fragment length polymorphism (AFLP) analysis is currently the most powerful and efficient technique for the generation of large numbers of anonymous DNA markers in plant and animal genomes. We have developed a protocol for high-throughput AFLP analysis that allows up to 70 000 polymorphic marker genotype determinations per week on a single automated DNA sequencer. This throughput is based on multiplexed PCR amplification of AFLP fragments using two different infrared dyelabeled primer combinations. The multiplexed AFLPs are resolved on a two-dye, model 4200 LI-COR ® automated DNA sequencer, and the digital images are scored using semi-automated scoring software specifically designed for complex AFLP banding patterns (AFLP-Quantar™). Throughput is enhanced by using high-quality genomic DNA templates obtained by a 96-well DNA isolation procedure. DA - 2001/2// PY - 2001/2// DO - 10.2144/01302tt04 VL - 30 IS - 2 SP - 348-+ SN - 0736-6205 ER - TY - JOUR TI - Genetic evidence and the origin of maize (Biology, archaeology) AU - Bennetzen, J AU - Buckler, E AU - Chandler, V AU - Doebley, J AU - Dorweiler, J AU - Gaut, B AU - Freeling, M AU - Hake, S AU - Kellogg, E AU - Poethig, RS AU - Walbot, V AU - Wessler, S T2 - LATIN AMERICAN ANTIQUITY AB - The origin of maize has been a topic of interest to both biologists and archaeologists. During the twentieth century, the view point that maize is a domesticated form of teosinte received convincing support from biological data and is now broadly accepted among biologists familiar with the issues and data. There is no support of any kind for an alternative view that maize is a hybrid of the grasses Zea diploperennis and Tripsacum . DA - 2001/3// PY - 2001/3// DO - 10.2307/971759 VL - 12 IS - 1 SP - 84-86 SN - 2325-5080 ER - TY - JOUR TI - Expression of a plant gene with sequence similarity to animal TGF-beta receptor interacting protein is regulated by brassinosteroids and required for normal plant development AU - Jiang, , JR AU - Clouse, SD T2 - PLANT JOURNAL AB - Summary Brassinosteroids (BRs) regulate the expression of numerous genes associated with plant development, and require the activity of a Ser/Thr receptor kinase to realize their effects. In animals, the transforming growth factor‐β (TGF‐β) family of peptides acts via Ser/Thr receptor kinases to have a major impact on several pathways involved in animal development and adult homeostasis. TGF‐β receptor‐interacting protein (TRIP‐1) was previously shown by others to be an intracellular substrate of the TGF‐β type II receptor kinase which plays an important role in TGF‐β signaling. TRIP‐1 is a WD‐repeat protein that also has a dual role as an essential subunit of the eukaryotic translation initiation factor eIF3 in animals, yeast and plants, thereby revealing a putative link between a developmental signaling pathway and the control of protein translation. In yeast, expression of a TRIP‐1 homolog has also been closely associated with cell proliferation and progression through the cell cycle. We report here the novel observation that transcript levels of TRIP‐1 homologs in plants are regulated by BR treatment under a variety of conditions, and that transgenic plants expressing antisense TRIP‐1 RNA exhibit a broad range of developmental defects, including some that resemble the phenotype of BR‐deficient and ‐insensitive mutants. This correlative evidence suggests that a WD‐domain protein with reported dual functions in vertebrates and fungi might mediate some of the molecular mechanisms underlying the regulation of plant growth and development by BRs. DA - 2001/4// PY - 2001/4// DO - 10.1046/j.1365-313x.2001.01007.x VL - 26 IS - 1 SP - 35-45 SN - 0960-7412 KW - brassinosteroids KW - TRIP-1 KW - eIF3 KW - receptor kinase KW - TGF-beta KW - antisense ER - TY - JOUR TI - Evolution of proteasomal ATPases AU - Wollenberg, K AU - Swaffield, JC T2 - MOLECULAR BIOLOGY AND EVOLUTION AB - In eukaryotic cells, the majority of proteins are degraded via the ATP-dependent ubiquitin/26S proteasome pathway. The proteasome is the proteolytic component of the pathway. It is a very large complex with a mass of around 2.5 MDa, consisting of at least 62 proteins encoded by 31 genes. The eukaryotic proteasome has evolved from a simpler archaebacterial form, similar in structure but containing only three different peptides. One of these peptides is an ATPase belonging to the AAA (Triple-A) family of ATPASES: Gene duplication and diversification has resulted in six paralogous ATPases being present in the eukaryotic proteasome. While sequence analysis studies clearly show that the six eukaryotic proteasomal ATPases have evolved from the single archaebacterial proteasomal ATPase, the deep node structures of the phylogenetic constructions lack resolution. Incorporating physical data to provide support for alternative phylogenetic hypotheses, we have constructed a model of a possible evolutionary history of the proteasomal ATPASES: DA - 2001/6// PY - 2001/6// DO - 10.1093/oxfordjournals.molbev.a003897 VL - 18 IS - 6 SP - 962-974 SN - 1537-1719 KW - proteasome KW - proteasomal ATPases KW - multiprotein complex KW - cross-linking KW - AAA ATPase KW - evolution ER - TY - JOUR TI - Design and synthesis of porphyrin-based optoelectronic gates AU - Ambroise, A AU - Wagner, RW AU - Rao, PD AU - Riggs, JA AU - Hascoat, P AU - Diers, , JR AU - Seth, J AU - Lammi, RK AU - Bocian, DF AU - Holten, D AU - Lindsey, JS T2 - CHEMISTRY OF MATERIALS AB - Two porphyrin-based optoelectronic gates and several prototypical redox-switching components of gates have been synthesized for studies in molecular photonics. Linear and T-shaped molecular optoelectronic gates contain a boron-dipyrrin (BDPY) dye as the input unit, a zinc (Zn) porphyrin as the transmission unit, a free base (Fb) porphyrin as the output unit, and a magnesium (Mg) porphyrin as the redox-switching unit. The linear gate and T gate were synthesized using a molecular building block approach. In the linear gate synthesis, a BDPY−Zn porphyrin dyad was coupled with a Fb porphyrin−Mg porphyrin dimer. The synthesis of the T gate utilized a Zn porphyrin bearing four different meso substituents: mesityl, 4-iodophenyl, 4-[2-(trimethylsilyl)ethynyl]phenyl, and 4-[2-triisopropyl)ethynyl]phenyl. Attachment of the three different groups to the Zn porphyrin was accomplished using successive Pd-mediated coupling reactions in the following sequence: Fb porphyrin (output unit), BDPY dye (input unit), and Mg porphyrin (redox-switching unit). Both the linear gate and T gate syntheses introduce the Mg porphyrin at the final step to minimize demetalation of the Mg porphyrin. Refinements to various components of these gates were investigated through the preparation of a ferrocene−porphyrin, a ferrocene−phthalocyanine, and a ferrocene−porphyrin−phthalocyanine. A dyad motif for studies of optically based redox switching was prepared that contains a derivative of Ru(bpy)3X2 coupled to a porphyrin. From these and related studies have emerged a number of design considerations for the development of refined optoelectronic gates. DA - 2001/3// PY - 2001/3// DO - 10.1021/cm000773m VL - 13 IS - 3 SP - 1023-1034 SN - 1520-5002 ER - TY - JOUR TI - Characterization of Escherichia coli type 1 pilus mutants with altered binding specificities AU - Harris, SL AU - Spears, PA AU - Havell, EA AU - Hamrick, TS AU - Horton, , JR AU - Orndorff, PE T2 - JOURNAL OF BACTERIOLOGY AB - ABSTRACT PCR mutagenesis and a unique enrichment scheme were used to obtain two mutants, each with a single lesion in fimH , the chromosomal gene that encodes the adhesin protein (FimH) of Escherichia coli type 1 pili. These mutants were noteworthy in part because both were altered in the normal range of cell types bound by FimH. One mutation altered an amino acid at a site previously shown to be involved in temperature-dependent binding, and the other altered an amino acid lining the predicted FimH binding pocket. DA - 2001/7// PY - 2001/7// DO - 10.1128/JB.183.13.4099-4102.2001 VL - 183 IS - 13 SP - 4099-4102 SN - 0021-9193 ER - TY - JOUR TI - Applying 3-PG, a simple process-based model designed to produce practical results, to data from loblolly pine experiments AU - Landsberg, J. J. AU - Johnsen, K. H. AU - Albaugh, T. J. AU - Allen, H. L. AU - McKeand, S. E. T2 - Forest Science DA - 2001/// PY - 2001/// VL - 47 IS - 1 SP - 43-51 ER - TY - JOUR TI - A screen for sequences up-regulated during heterocyst development in Anabaena sp strain PCC 7120 AU - Curtis, SE AU - Hebbar, PB T2 - ARCHIVES OF MICROBIOLOGY DA - 2001/5// PY - 2001/5// DO - 10.1007/s002030100267 VL - 175 IS - 5 SP - 313-322 SN - 0302-8933 KW - Anabaena sp strain PCC 7120 KW - cyanobacteria KW - heterocyst development KW - nitrogen starvation KW - genome screening KW - up-regulated genes ER - TY - JOUR TI - Waiting times to appearance and dominance of advantageous mutants: estimation based on the likelihood AU - Radmacher, M. D. AU - Kepler, T. B. T2 - Mathematical Biosciences DA - 2001/// PY - 2001/// VL - 170 IS - 1 SP - 59-77 ER - TY - JOUR TI - Variation among isolates of Fusarium graminearum associated with Fusarium head blight in North Carolina AU - Walker, SL AU - Leath, S AU - Hagler, WM AU - Murphy, JP T2 - PLANT DISEASE AB - Fusarium head blight (FHB) can reduce yield of wheat and decrease the value of harvested grain by accumulation of detrimental toxins. Understanding the variability of the fungal population associated with infection could improve disease control strategies. Sixty-six isolates of Fusarium graminearum associated with FHB were collected in North Carolina and tested for in vitro growth rate, in vitro production of deoxynivalenol (DON) and zearalenone, and pathogenicity on three cultivars of soft red winter wheat. Significant differences among isolates were found for all three traits. Randomly Amplified Polymorphic DNA (RAPD) analysis revealed high levels of genotypic diversity among isolates. Isolates of F. graminearum, F. culmorum, and F. avenaceum acquired from the Pennsylvania State University Fusarium Center were included for comparison in all tests. In vivo levels of DON were measured for the five isolates associated with the highest levels of disease and the five isolates associated with the lowest levels of disease, and no significant differences were found. However, all ten isolates produced detectable levels of DON in vivo. Mean disease ratings ranged from 3.4 to 96.4%, in vitro (DON) levels ranged from 0 to 7176.2 ppm, and zearalenone ranged from 0 to 354.7 ppm, among isolates. A multiple regression model using in vitro growth, in vitro DON, and zearalenone production, collection location, wheat cultivar of isolate origin, plot, tillage conditions, and previous crop as independent variables and percent blighted tissue as the dependent variable was developed. The cumulative R 2 value for the model equaled 0.27 with in vitro rate of growth making the largest contribution. Analysis of phenotype and genotype among isolates demonstrated diversity in a single plot, in a single location, and in North Carolina. Genotypic and phenotypic diversity were significant under both conventional and reduced tillage conditions, and diversity was high regardless of whether the previous crop had been a host or non-host for F. graminearum. These data indicate a variable pathogen population of F. graminearum exists in North Carolina, and members of this population can be both highly pathogenic on wheat and produce high levels of detrimental toxins, indicating a potential threat for problems with FHB within the state. DA - 2001/4// PY - 2001/4// DO - 10.1094/PDIS.2001.85.4.404 VL - 85 IS - 4 SP - 404-410 SN - 0191-2917 KW - resistance ER - TY - CHAP TI - The ribonuclease P family AU - Hall, T. A. AU - Brown, J. W. T2 - Ribonucleases: Pt. A CN - QP601 .M49 v. 341-342 [Hill] PY - 2001/// VL - 341 SP - 56-77 PB - San Diego, CA: Academic Press ER - TY - JOUR TI - The 5 ' end of the pea ferredoxin-1 mRNA mediates rapid and reversible light-directed changes in translation in tobacco AU - Hansen, ER AU - Petracek, ME AU - Dickey, LF AU - Thompson, WF T2 - PLANT PHYSIOLOGY AB - Abstract Ferredoxin-1 (Fed-1) mRNA contains an internal light response element (iLRE) that destabilizes mRNA when light-grown plants are placed in darkness. mRNAs containing this element dissociate from polyribosomes in the leaves of transgenic tobacco (Nicotiana tabacum) plants transferred to the dark for 2 d. Here, we report in vivo labeling experiments with a chloramphenicol acetyl transferase mRNA fused to theFed-1 iLRE. Our data indicate that theFed-1 iLRE mediates a rapid decline in translational efficiency and that iLRE-containing mRNAs dissociate from polyribosomes within 20 min after plants are transferred to darkness. Both events occur before the decline in mRNA abundance, and polyribosome association is rapidly reversible if plants are re-illuminated. These observations support a model in which Fed-1 mRNA in illuminated leaves is stabilized by its association with polyribosomes, and/or by translation. In darkness a large portion of the mRNA dissociates from polyribosomes and is subsequently degraded. We also show that a significant portion of total tobacco leaf mRNA is shifted from polyribosomal to non-polyribosomal fractions after 20 min in the dark, indicating that translation of other mRNAs is also rapidly down-regulated in response to darkness. This class includes some, but not all, cytoplasmic mRNAs encoding proteins involved in photosynthesis. DA - 2001/2// PY - 2001/2// DO - 10.1104/pp.125.2.770 VL - 125 IS - 2 SP - 770-778 SN - 0032-0889 ER - TY - JOUR TI - Studies related to the design and synthesis of a molecular octal counter AU - Gryko, D AU - Li, JZ AU - Diers, , JR AU - Roth, KM AU - Bocian, DF AU - Kuhr, WG AU - Lindsey, JS T2 - JOURNAL OF MATERIALS CHEMISTRY AB - An approach to the storage of multiple bits of information at the molecular level employs molecules with a large number of distinct oxidation states. Europium triple-decker sandwich molecules composed of porphyrins and phthalocyanines afford four cationic states and are very attractive for molecular information-storage applications. A larger number of states can be achieved by combinations of triple deckers that afford interleaved oxidation potentials. In order to identify suitable candidates for effective interleaving of oxidation potentials, a library of 19 new triple-decker complexes was prepared. Electron-donating groups have been attached to the porphyrin and/or phthalocyanine moieties in order to achieve oxidation states in the low potential regime. The triple deckers are of three different types: (Pc)Eu(Pc)Eu(Por), (Pc)Eu(Por)Eu(Pc), and (Por)Eu(Pc)Eu(Por). The solution electrochemistry of each member of the library was examined. These studies revealed suitable pairs of triple deckers that provide effective interleaving of oxidation potentials. Six triple deckers of type (Pc)Eu(Pc)Eu(Por) were derivatized with a thioacetyl or thiocyanate group on the porphyrin unit for attachment to an electroactive surface. Each of the S-(acetylthio)-derivatized triple deckers forms a self-assembled monolayer (SAM) on Au viain situ cleavage of the thiol protecting group. The SAM of each triple decker is electrochemically robust and exhibits four, well-resolved reversible oxidation waves. Upon disconnection from the source of applied potential, the triple-decker SAMs retain charge for tens to hundreds of seconds. The exact value of the charge-retention time depends on the specific porphyrin/phthalocyanine in the triple decker and the particular oxidation state of the molecules in the SAM (e.g., mono- vs. di- vs. tri- vs. tetracation). For all of the triple-decker SAMs, the charge-retention time monotonically increases as the oxidation state of the molecules in the SAM increases. Collectively, the studies suggest that the triple-decker complexes are excellent candidates for multibit molecular information storage elements. DA - 2001/// PY - 2001/// DO - 10.1039/b008224o VL - 11 IS - 4 SP - 1162-1180 SN - 0959-9428 ER - TY - JOUR TI - Regeneration of transgenic loblolly pine (Pinus taeda L.) from zygotic embryos transformed with Agrobacterium tumefaciens AU - Tang, W AU - Sederoff, R AU - Whetten, R T2 - PLANTA DA - 2001/10// PY - 2001/10// DO - 10.1007/s004250100566 VL - 213 IS - 6 SP - 981-989 SN - 1432-2048 KW - genetic transformation KW - beta-glucuronidase gene KW - Pinus (transformation) KW - plant DNA/T-DNA junction analysis KW - transgenic pine KW - zygotic embryo ER - TY - JOUR TI - Nursery and field establishment techniques to improve seedling growth of three Costa Rican hardwoods AU - Wightman, KE AU - Shear, T AU - Goldfarb, B AU - Haggar, J T2 - NEW FORESTS DA - 2001/// PY - 2001/// DO - 10.1023/A:1012020023446 VL - 22 IS - 1-2 SP - 75-96 SN - 1573-5095 KW - Calophyllum brasiliense KW - compost KW - Cordia alliodora KW - fertilization KW - herbicide KW - Hyeronima alchorneoides KW - native species KW - reforestation KW - root trainers KW - weed control ER - TY - JOUR TI - Mechanisms of excited-state energy-transfer gating in linear versus branched multiporphyrin arrays AU - Lammi, RK AU - Wagner, RW AU - Ambroise, A AU - Diers, , JR AU - Bocian, DF AU - Holten, D AU - Lindsey, JS T2 - JOURNAL OF PHYSICAL CHEMISTRY B AB - We have investigated electrochemical switching of excited-state electronic energy migration in two optoelectronic gates with different architectures. Each gate consists of diarylethyne-linked subunits: a boron-dipyrrin (BDPY) input unit, a Zn-porphyrin transmission unit, a free-base-porphyrin (Fb-porphyrin) output unit, and a Mg-porphyrin redox-switched site connected either to the Fb porphyrin (linear gate) or to the Zn porphyrin (branched, T gate). Both the linear and branched architectures show Fb-porphyrin emission when the Mg porphyrin is neutral and nearly complete quenching when the Mg porphyrin is oxidized to the π-cation radical. To determine the mechanism of gating, we undertook a systematic photophysical study of the gates and their dyad and triad components in neutral and oxidized forms, using static and time-resolved optical spectroscopy. Two types of photoinduced energy-transfer (and/or charge-transfer) processes are involved in gate operation: transfer between adjacent subunits and transfer between nonadjacent subunits. All of the individual energy-transfer steps that funnel input light energy to the fluorescent output element in the neutral systems are highly efficient, occurring primarily by a through-bond mechanism. Similarly efficient energy-transfer processes occur between the BDPY and the Zn and Fb porphyrins in the oxidized systems, but are followed by rapid and efficient energy/charge transfer to the redox-switched site and consequent nonradiative deactivation. Energy/charge transfer between nonadjacent porphyrins, which occurs principally by superexchange, is crucial to the operation of the T gate. Collectively, our studies elucidate the photophysics of gating and afford great flexibility and control in the design of more elaborate arrays for molecular photonics applications. DA - 2001/6/7/ PY - 2001/6/7/ DO - 10.1021/jp010857y VL - 105 IS - 22 SP - 5341-5352 SN - 1520-5207 ER - TY - JOUR TI - Locations of carbohydrate sites on alphavirus glycoproteins show that E1 forms an icosahedral scaffold AU - Pletnev, SV AU - Zhang, W AU - Mukhopadhyay, S AU - Fisher, BR AU - Hernandez, R AU - Brown, DT AU - Baker, TS AU - Rossmann, MG AU - Kuhn, RJ T2 - CELL AB - There are 80 spikes on the surface of Sindbis virus arranged as an icosahedral surface lattice. Each spike consists of three copies of each of the glycoproteins E1 and E2. There are two glycosylation sites on E1 and two on E2. These four sites have been located by removal of the glycosylation recognition motifs using site-specific mutagenesis, followed by cryoelectron microscopy. The positions of these sites have demonstrated that E2 forms the protruding spikes and that E1 must be long and narrow, lying flat on the viral surface, forming an icosahedral scaffold analogous to the arrangement of the E glycoprotein in flaviviruses. This arrangement of E1 leads to both dimeric and trimeric intermolecular contacts, consistent with the observed structural changes that occur on fusion with host cell membranes, suggesting a similar fusion mechanism for alpha- and flaviviruses. DA - 2001/4/6/ PY - 2001/4/6/ DO - 10.1016/S0092-8674(01)00302-6 VL - 105 IS - 1 SP - 127-136 SN - 0092-8674 ER - TY - JOUR TI - Improved inference of mutation rates - II. Generalization of the Luria-Delbruck distribution for realistic cell-cycle time distributions AU - Oprea, M AU - Kepler, TB T2 - THEORETICAL POPULATION BIOLOGY AB - In the first paper of this series (Kepler and Oprea, Theor. Popul. Biol. 2001) we found a continuum approximation of the Luria–Delbrück distribution in terms of a scaled variable related to the proportion of mutants in the culture. Here we show that the Luria–Delbrück distribution is inaccurate when realistic division processes are being considered due to the non-Markovian character of the cell cycle. We derive the expectation of the proportion of mutants in the culture for arbitrary cell-cycle time distributions. We then introduce a two-parameter generalization of the continuum Luria–Delbrück distribution for two of the more commonly used cell-cycle time distributions: gamma and shifted exponential. We obtain the generalized distribution by defining a map from the actual parameters to “effective” parameters. The effective mutation rate is obtained analytically, while the effective population size is obtained by fitting simulation data. Our simulations show that the second parameter depend mostly on the coefficient of variation of the cell-cycle time distribution. DA - 2001/2// PY - 2001/2// DO - 10.1006/tpbi.2000.1504 VL - 59 IS - 1 SP - 49-59 SN - 0040-5809 ER - TY - JOUR TI - Impact of powdery mildew and leaf rust on milling and baking quality of soft red winter wheat AU - Everts, KL AU - Leath, S AU - Finney, PL T2 - PLANT DISEASE AB - Changes in milling and baking quality (especially flour yield) of soft red winter wheat can have a large economic impact on flour mills. To determine the relationship between early-season powdery mildew and late-season leaf rust on flour yield, flour protein, alkaline water retention capacity, and kernel texture (softness equivalent), a study was conducted over 2 years at Kinston and Plymouth, NC. Different levels of powdery mildew and leaf rust developed on three winter wheat cultivars that varied in levels of disease resistance, the presence of seed treatment, and the presence and timing of foliar fungicide application. In Kinston and Plymouth in 1989-90, where leaf rust occurred early, the softness equivalent score was lower in wheat grown from seed treated with triadimenol. The following year, when the leaf rust epidemic increased later, foliar fungicide application reduced disease and resulted in lower softness equivalent scores in both Plymouth and Kinston for cv. Saluda and in Kinston for cv. Coker 983. A regression model was developed to describe the relationship between the log of the area under the disease progress curves and adjusted flour yield (AFY). The AFY of Saluda was reduced in the presence of powdery mildew such that %AFY = 103.96 - 0.92 (log AUMPC). DA - 2001/4// PY - 2001/4// DO - 10.1094/PDIS.2001.85.4.423 VL - 85 IS - 4 SP - 423-429 SN - 1943-7692 KW - Blumeria graminis f. sp tritici KW - crop losses KW - Puccinia triticina ER - TY - JOUR TI - Assessing the association between the geographic distribution of deer ticks and seropositivity rates to various tick-transmitted disease organisms in dogs AU - Hinrichsen, Virginia L. AU - Whitworth, Ulysses G. AU - Breitschwerdt, Edward B. AU - Hegarty, Barbara C. AU - Mather, Thomas N. T2 - Journal of the American Veterinary Medical Association AB - To determine whether the geographic distribution of deer ticks (Ixodes scapularis) was associated with the distribution of dogs seropositive for various tick-transmitted disease organisms (ie, Borrelia burgdorferi, Rickettsia rickettsii, the human granulocytic ehrlichiosis [HGE] agent, Ehrlichia canis, and Bartonella vinsonii subsp berkhoffii).Serologic survey.Serum samples from 277 dogs in animal shelters and veterinary hospitals in Rhode Island.Overall, 143 (52%) dogs were seropositive for B burgdorferi, 59 (21.3%) were seropositive for R rickettsii, 40 (14.4%) were seropositive for the HGE agent, 8 (2.9%) were seropositive for E canis, and 6 (2.2%) were seropositive for B vinsonii. Regression analysis indicated that the natural logarithm of nymphal deer tick abundance was correlated with rate of seropositivity to the HGE agent and to B burgdorferi but not to rate of seropositivity to R rickettsii, E canis, or B vinsonii. Percentages of samples seropositive for B burgdorferi, R rickettsii, the HGE agent, and E canis were significantly higher for samples from the southwestern part of the state where ticks in general and deer ticks in particular are abundant than for samples from the northern and eastern portions of the state, where ticks are relatively rare.Results suggested that all 5 disease agents are in Rhode Island and pose a risk to dogs and humans. Knowledge concerning tick distributions may be useful in predicting the pattern of disease associated with particular tick species and may aid diagnostic, prevention, and control efforts. DA - 2001/4// PY - 2001/4// DO - 10.2460/javma.2001.218.1092 VL - 218 IS - 7 SP - 1092-1097 J2 - Journal of the American Veterinary Medical Association LA - en OP - SN - 0003-1488 UR - http://dx.doi.org/10.2460/javma.2001.218.1092 DB - Crossref ER - TY - JOUR TI - Vertebrate serpins: Construction of a conflict-free phylogeny by combining exon-intron and diagnostic site analyses AU - Ragg, H AU - Lokot, T AU - Kamp, PB AU - Atchley, WR AU - Dress, A T2 - MOLECULAR BIOLOGY AND EVOLUTION AB - A combination of three independent biological features, genomic organization, diagnostic amino acid sites, and rare indels, was used to elucidate the phylogeny of the vertebrate serpin (serine protease inhibitor) superfamily. A strong correlation between serpin gene families displaying (1) a conserved exon-intron pattern and (2) family-specific combinations of amino acid residues at specific sites suggests that present-day vertebrates encompass six serpin gene families which evolved from primordial genes by massive intron insertion before or during early vertebrate radiation. Introns placed at homologous positions in the gene sequences in combination with diagnostic sequence characters may also constitute a reliable kinship indicator for other protein superfamilies. DA - 2001/4// PY - 2001/4// DO - 10.1093/oxfordjournals.molbev.a003838 VL - 18 IS - 4 SP - 577-584 SN - 1537-1719 KW - molecular evolution KW - serpins KW - exon-intron structure KW - diagnostic sites KW - heparin cofactor II ER - TY - JOUR TI - The role of cell differentiation state and HMG-I/Y in the expression of transgenes flanked by matrix attachment regions AU - Ascenzi, R AU - Ingram, JL AU - Massel, M AU - Thompson, WF AU - Spiker, S AU - Weissinger, AK T2 - TRANSGENIC RESEARCH DA - 2001/// PY - 2001/// DO - 10.1023/A:1012082602587 VL - 10 IS - 5 SP - 465-470 SN - 0962-8819 KW - cell differentiation and proliferation KW - chromatin KW - matrix KW - scaffold attachment region (MAR/SAR) KW - plant high mobility group-I/Y protein (HMG-I/Y) KW - transgene expression KW - tobacco ER - TY - JOUR TI - Synthesis and excited-state photodynamics of perylene-porphyrindyads. Part 3, Effects of perylene, linker, and connectivity on ultrafast energy transfer AU - Yang, S. I. AU - Lammi, R. K. AU - Prathapan, S. AU - Miller, M. A. AU - Seth, J. AU - Diers, J. R. AU - Bocian, D. F. AU - Lindsey, Jonathan AU - Holten, D. T2 - Journal of Materials Chemistry AB - New perylene–porphyrin dyads have been designed that exhibit superior light-harvesting and energy-utilization activity compared with earlier generations of structurally related dyads. The new dyads consist of a perylene mono(imide) dye (PMI) connected to a porphyrin (Por) via an ethynylphenyl (ep) linker. The PMI–ep–Por arrays were prepared with the porphyrin as either a zinc or magnesium complex (Por = Zn or Mg) or a free-base form (Por = Fb). The absorption properties of the perylene complement those of the porphyrin. Following excitation of the perylene (forming PMI*) in toluene, each array exhibits ultrafast (kENT ≥ (0.5 ps)−1) and essentially quantitative energy transfer from PMI* to the ground-state porphyrin (forming Por*). In each of the arrays, the properties of the excited porphyrin (lifetime, fluorescence yield, etc.) are basically unperturbed from those of the isolated pigment. Thus, following energy transfer, the excited porphyrin is not quenched by deleterious reactions involving the perylene accessory unit that would otherwise limit the ability of Por* to emit light or transfer energy to another stage in a molecular photonic device. Collectively, the PMI–ep–Por dyads represent the successful result of a molecular design strategy to produce arrays with excellent properties for use as light-input and energy-transduction elements for applications in molecular optoelectronics. DA - 2001/// PY - 2001/// DO - 10.1039/b102741g VL - 11 IS - 10 SP - 2420–2430 ER - TY - PAT TI - Method of treating alopecia AU - Smart, R. C. AU - Oh, H.-S. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Linear mixed models with flexible distributions of random effects for longitudinal data AU - Zhang, DW AU - Davidian, M T2 - BIOMETRICS AB - Normality of random effects is a routine assumption for the linear mixed model, but it may be unrealistic, obscuring important features of among-individual variation. We relax this assumption by approximating the random effects density by the seminonparameteric (SNP) representation of Gallant and Nychka (1987, Econometrics 55, 363-390), which includes normality as a special case and provides flexibility in capturing a broad range of nonnormal behavior, controlled by a user-chosen tuning parameter. An advantage is that the marginal likelihood may be expressed in closed form, so inference may be carried out using standard optimization techniques. We demonstrate that standard information criteria may be used to choose the tuning parameter and detect departures from normality, and we illustrate the approach via simulation and using longitudinal data from the Framingham study. DA - 2001/9// PY - 2001/9// DO - 10.1111/j.0006-341X.2001.00795.x VL - 57 IS - 3 SP - 795-802 SN - 0006-341X KW - longitudinal data KW - multimodality KW - random effects KW - seminonparametric density KW - semiparametric mixed effects model KW - skewness ER - TY - JOUR TI - Infection of Fetal Feline Brain Cells in Culture with Bartonella henselae AU - Munana, K. R. AU - Vitek, S. M. AU - Hegarty, B. C. AU - Kordick, D. L. AU - Breitschwerdt, E. B. T2 - Infection and Immunity AB - ABSTRACT Bartonella henselae is known to cause central nervous system (CNS) disease in humans, and neurological signs have been observed in experimentally infected cats. However, the pathogenesis of CNS disease remains unclear. This study was undertaken to determine whether B. henselae infects feline fetal brain cells in vitro. Microglial-cell- and astrocyte-enriched cultures were inoculated with B. henselae . Giménez staining identified bacterial organisms within microglial cells by day 7 postinoculation. The viability of the intracellular bacteria was demonstrated by incubating cultures with gentamicin and plating cell lysate on agar. Electron microscopy identified intracellular organisms with characteristic Bartonella morphology but identified no ultrastructural abnormalities within infected microglial cells. No evidence of infection was seen in Bartonella -inoculated astrocyte cultures. These findings suggest a role for microglia in the pathogenesis of B. henselae -associated neurological disease. DA - 2001/1/1/ PY - 2001/1/1/ DO - 10.1128/IAI.69.1.564-569.2001 VL - 69 IS - 1 SP - 564-569 J2 - Infection and Immunity LA - en OP - SN - 0019-9567 UR - http://dx.doi.org/10.1128/IAI.69.1.564-569.2001 DB - Crossref ER - TY - PAT TI - High-density non-volatile memory devices incorporating sandwich coordination compounds AU - Lindsey, J. S. C2 - 2001/// DA - 2001/// PY - 2001/// ER - TY - JOUR TI - Generation of Intron-Containing, ER-Localized, Soluble-Modified Green Fluorescent Protein Genes for use in Plant Transformation AU - Mankin, S.L. AU - Thompson, W.F. T2 - Plant Molecular Biology Reporter DA - 2001/// PY - 2001/// DO - 10.1007/bf02824074 VL - 19 IS - 1 SP - 13–26 ER - TY - JOUR TI - Formation of antibiotic, biodegradable polymers by processing with Irgasan DP300R (Triclosan) and its inclusion compound with beta-cyclodextrin AU - Lu, J. AU - Hill, M. A. AU - Hood, M. AU - Greeson, D. F. AU - Horton, J. R. AU - Orndorff, P. E. AU - Herndon, A. S. AU - Tonelli, A. E. T2 - Journal of Applied Polymer Science AB - The inclusion compound (IC) between the FDA-approved antibacterial Irgasan DP300 (Trichlosan), and β-cyclodextrin (CD) has been formed. When the Irgasan–β-CD–IC is embedded in biodegradeable/bioabsorbable films of poly(ϵ-caprolactone) (PCL) at low levels (a few wt %), they are rendered resistant to the growth of E. coli bacteria. When these same PCL films embedded with Irgasan–β-CD–IC are used as the adhesive for laminating cotton fabrics, we observe the resulting cotton laminates to also be resistant to the growth of E. coli bacteria. These results hold promise for the fabrication of bacteria-resistant polymer films and fibers, as well as antibacterial fabrics, by means of simple melt processing with Irgasan–β-CD–IC. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 300–309, 2001 DA - 2001/// PY - 2001/// DO - 10.1002/app.1852.abs VL - 82 IS - 2 SP - 300-309 ER - TY - JOUR TI - Calpain inhibition protects against virus-induced apoptotic myocardial injury AU - DeBiasi, RL AU - Edelstein, CL AU - Sherry, B AU - Tyler, KL T2 - JOURNAL OF VIROLOGY AB - Viral myocarditis is an important cause of human morbidity and mortality for which reliable and effective therapy is lacking. Using reovirus strain 8B infection of neonatal mice, a well-characterized experimental model of direct virus-induced myocarditis, we now demonstrate that myocardial injury results from apoptosis. Proteases play a critical role as effectors of apoptosis. The activity of the cysteine protease calpain increases in reovirus-infected myocardiocytes and can be inhibited by the dipeptide alpha-ketoamide calpain inhibitor Z-Leu-aminobutyric acid-CONH(CH(2))3-morpholine (CX295). Treatment of reovirus-infected neonatal mice with CX295 protects them against reovirus myocarditis as documented by (i) a dramatic reduction in histopathologic evidence of myocardial injury, (ii) complete inhibition of apoptotic myocardial cell death as identified by terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling, (iii) a reduction in serum creatine phosphokinase, and (iv) improved weight gain. These findings are the first evidence for the importance of a calpain-associated pathway of apoptotic cell death in viral disease. Inhibition of apoptotic signaling pathways may be an effective strategy for the treatment of viral disease in general and viral myocarditis in particular. DA - 2001/1// PY - 2001/1// DO - 10.1128/JVI.75.1.351-361.2001 VL - 75 IS - 1 SP - 351-361 SN - 1098-5514 ER - TY - JOUR TI - Overwintering of Frankliniella fusca (Thysanoptera : Thripidae) on winter annual weeds infected with Tomato spotted wilt virus and patterns of virus movement between susceptible weed hosts AU - Groves, RL AU - Walgenbach, JF AU - Moyer, JW AU - Kennedy, GG T2 - PHYTOPATHOLOGY AB - Overwintering of tobacco thrips, Frankliniella fusca, was investigated on common winter annual host plants infected with Tomato spotted wilt virus (TSWV). Populations of tobacco thrips produced on TSWV-infected plants did not differ from those produced on healthy plants, whereas populations varied greatly among host plant species. The mean per plant populations of F. fusca averaged 401, 162, and 10 thrips per plant on Stellaria media, Scleranthus annuus, and Sonchus asper, respectively, during peak abundance in May. Adult F. fusca collected from plant hosts were predominately brachypterous throughout the winter and early spring, but macropterous forms predominated in late spring. Weed hosts varied in their ability to serve as overwintering sources of TSWV inoculum. Following the initial infection by TSWV in October 1997, 75% of Scleranthus annuus and Stellaria media retained infection over the winter and spring season, whereas only 17% of Sonchus asper plants remained infected throughout the same interval. Mortality of TSWV-infected Sonchus asper plants exceeded 25%, but mortality of infected Stellaria media and Scleranthus annuus did not exceed 8%. TSWV transmission by thrips produced on infected plants was greatest on Stellaria media (18%), intermediate on Scleranthus annuus (6%), and lowest on Sonchus asper (2%). Very few viruliferous F. fusca were recovered from soil samples collected below infected wild host plants. Vegetative growth stages of Stellaria media, Sonchus asper, and Ranunculus sardous were more susceptible to F. fusca transmission of TSWV than flowering growth stages, whereas both growth stages of Scleranthus annuus were equally susceptible. In a field study to monitor the spatial and temporal patterns of virus movement from a central source of TSWV-infected Stellaria media to adjacent plots of R. sardous, the incidence of infection in R. sardous plots increased from <1% in March to >42% in June 1999. Infection levels in the Stellaria media inoculum source remained high throughout the experiment, averaging nearly 80% until June 1999 when all Stellaria media plants had senesced. Dispersal of TSWV from the inoculum source extended to the limits of the experimental plot (>37 m). Significant directional patterns of TSWV spread to the R. sardous plots were detected in April and May but not in June. R. sardous infections were detected as early as March and April, suggesting that overwintering inoculum levels in an area can increase rapidly during the spring in susceptible weed hosts prior to planting of susceptible crops. This increase in the abundance of TSWV inoculum sources occurs at a time when vector populations are increasing rapidly. The spread of TSWV among weeds in the spring serves to bridge the period when overwintered inoculum sources decline and susceptible crops are planted. DA - 2001/9// PY - 2001/9// DO - 10.1094/PHYTO.2001.91.9.891 VL - 91 IS - 9 SP - 891-899 SN - 1943-7684 KW - F. occidentalis ER - TY - JOUR TI - Overcoming host- and pathogen-mediated resistance in tomato and tobacco maps to the M RNA of Tomato spotted wilt virus AU - Hoffmann, K AU - Qiu, WP AU - Moyer, JW T2 - MOLECULAR PLANT-MICROBE INTERACTIONS AB - A viral genetic system was used to map the determinants of the ability of Tomato spotted wilt virus (TSWV) to overcome the R gene (Sw-5) in tomato and the resistance conferred by the nucleocapsid gene of TSWV (N gene) in tobacco. A complete set of reassortant genotypes was generated from TSWV isolates A and D. TSWV-A was able to overcome the Sw-5 gene in tomato and the TSWV N gene in tobacco, whereas TSWV-D was repressed by both forms of resistance. The ability to overcome both forms of resistance was associated with the M RNA segment of TSWV-A (M(A)). Overcoming the Sw-5 gene was linked solely to the presence of M(A), and the ability of M(A) to overcome the TSWV N gene was modified by the L RNA and the S RNA of TSWV-A, which is consistent with previous reports that suggest that the nucleocapsid gene is not the primary determinant for overcoming the nucleocapsid-mediated resistance. Sequence analysis of the M RNA segment of TSWV-A, -D, and the type isolate BR-01 revealed multiple differences in the coding and noncoding regions, which prevented identification of the resistance-breaking nucleotide sequences. DA - 2001/2// PY - 2001/2// DO - 10.1094/mpmi.2001.14.2.242 VL - 14 IS - 2 SP - 242-249 SN - 1943-7706 ER - TY - JOUR TI - The drosophila genes disconnected and disco-related are redundant with respect to larval head development and accumulation of mRNAs from deformed target genes AU - Mahaffey, J. W. AU - Griswold, C. M. AU - Cao, Q. M. T2 - Genetics DA - 2001/// PY - 2001/// VL - 157 IS - 1 SP - 225-236 ER - TY - JOUR TI - Joint linkage and linkage disequilibrium mapping in natural populations AU - Wu, R. L. AU - Zeng, Z. B. T2 - Genetics DA - 2001/// PY - 2001/// VL - 157 IS - 2 SP - 899-909 ER - TY - JOUR TI - Exposure to low pH is not required for penetration of mosquito cells by Sindbis virus AU - Hernandez, R AU - Luo, TC AU - Brown, DT T2 - JOURNAL OF VIROLOGY AB - It is widely held that the penetration of cells by alphaviruses is dependent on exposure to the acid environment of an endosome. The alphavirus Sindbis virus replicates in both vertebrate and invertebrate cell cultures. We have found that exposure to an acid environment may not be required for infection of cells of the insect host. In this work, we investigated the effects of two agents (NH(4)Cl and chloroquine), which raise the pH of intracellular compartments (lysosomotropic weak bases) on the infection and replication of Sindbis virus in cells of the insect host Aedes albopictus. The results show that both of these agents increase the pH of endosomes, as indicated by protection against diphtheria toxin intoxication. NH(4)Cl blocked the production of infectious virus and blocked virus RNA synthesis when added prior to infection. Chloroquine, in contrast to its effect on vertebrate cells, had no inhibitory effect on infectious virus production in mosquito cells even when added prior to infection. Treatment with NH(4)Cl did not prevent the penetration of virus RNA into the cell cytoplasm or translation of the RNA to produce a precursor to virus nonstructural proteins. These data suggest that while these two drugs raise the pH of endosomes, they do not block insect cell penetration. These data support previous results published by our laboratory suggesting that exposure to an acid environment within the cell may not be an obligatory step in the process of infection of cells by alphaviruses. DA - 2001/2// PY - 2001/2// DO - 10.1128/jvi.75.4.2010-2013.2001 VL - 75 IS - 4 SP - 2010-2013 SN - 0022-538X ER - TY - JOUR TI - Dual interaction of a geminivirus replication accessory factor with a viral replication protein and a plant cell cycle regulator AU - Settlage, SB AU - Miller, AB AU - Gruissem, W AU - Hanley-Bowdoin, L T2 - VIROLOGY AB - Geminiviruses replicate their small, single-stranded DNA genomes through double-stranded DNA intermediates in plant nuclei using host replication machinery. Like most dicot-infecting geminiviruses, tomato golden mosaic virus encodes a protein, AL3 or C3, that greatly enhances viral DNA accumulation through an unknown mechanism. Earlier studies showed that AL3 forms oligomers and interacts with the viral replication initiator AL1. Experiments reported here established that AL3 also interacts with a plant homolog of the mammalian tumor suppressor protein, retinoblastoma (pRb). Analysis of truncated AL3 proteins indicated that pRb and AL1 bind to similar regions of AL3, whereas AL3 oligomerization is dependent on a different region of the protein. Analysis of truncated AL1 proteins located the AL3-binding domain between AL1 amino acids 101 and 180 to a region that also includes the AL1 oligomerization domain and the catalytic site for initiation of viral DNA replication. Interestingly, the AL3-binding domain was fully contiguous with the domain that mediates AL1/pRb interactions. The potential significance of AL3/pRb binding and the coincidence of the domains responsible for AL3, AL1, and pRb interactions are discussed. DA - 2001/1/20/ PY - 2001/1/20/ DO - 10.1006/viro.2000.0719 VL - 279 IS - 2 SP - 570-576 SN - 0042-6822 ER - TY - JOUR TI - Immunodiagnosis of Ehrlichia canis Infection with Recombinant Proteins AU - McBride, J. W. AU - Corstvet, R. E. AU - Breitschwerdt, E. B. AU - Walker, D. H. T2 - Journal of Clinical Microbiology AB - Ehrlichia canis causes a potentially fatal rickettsial disease of dogs that requires rapid and accurate diagnosis in order to initiate appropriate therapy leading to a favorable prognosis. We recently reported the cloning of two immunoreactive E. canis proteins, P28 and P140, that were applicable for serodiagnosis of the disease. In the present study we cloned a new immunoreactive E. canis surface protein gene of 1,170 bp, which encodes a protein with a predicted molecular mass of 42.6 kDa (P43). The P43 gene was not detected in E. chaffeensis DNA by Southern blot, and antisera against recombinant P43 (rP43) did not react with E. chaffeensis as detected by indirect fluorescent antibody (IFA) assay. Forty-two dogs exhibiting signs and/or hematologic abnormalities associated with canine ehrlichiosis were tested by IFA assay and by recombinant Western immunoblot. Among the 22 samples that were IFA positive for E. canis, 100% reacted with rP43, 96% reacted with rP28, and 96% reacted with rP140. The specificity of the recombinant proteins compared to the IFAs was 96% for rP28, 88% for P43 and 63% for P140. The results of this study demonstrate that the rP43 and rP28 are sensitive and reliable serodiagnostic antigens for E. canis infections. DA - 2001/1/1/ PY - 2001/1/1/ DO - 10.1128/JCM.39.1.315-322.2001 VL - 39 IS - 1 SP - 315-322 J2 - Journal of Clinical Microbiology LA - en OP - SN - 0095-1137 UR - http://dx.doi.org/10.1128/JCM.39.1.315-322.2001 DB - Crossref ER - TY - JOUR TI - Coinfection with Three Ehrlichia Species in Dogs from Thailand and Venezuela with Emphasis on Consideration of 16S Ribosomal DNA Secondary Structure AU - Suksawat, J. AU - Pitulle, C. AU - Arraga-Alvarado, C. AU - Madrigal, K. AU - Hancock, S. I. AU - Breitschwerdt, E. B. T2 - Journal of Clinical Microbiology AB - As part of a larger study to investigate tick-borne infections in dogs from Thailand and Venezuela, documentation of coinfection with three Ehrlichia species in two dogs, one from each country, became the focus of the present study. Although neither dog had clinical signs attributable to ehrlichiosis, both dogs were anemic and neutropenic and the Thai dog was thrombocytopenic. Genus- and species-specific PCR targeting the 16S rRNA genes indicated that both dogs were coinfected with Ehrlichia canis, E. platys, and E. equi. To our knowledge, these results provide the first molecular documentation for the presence of E. equi in dogs from these countries. Using universal bacterial PCR primers, one nearly full-length 16S rRNA gene could be amplified from each dog. The sequences were identical to each other and almost identical to that of E. platys (AF156784), providing the first E. platys 16S ribosomal DNA (rDNA) sequences reported from these two geographically divergent countries. To determine whether these sequence differences allow differentiation between these two strains and other published 16S rDNA E. platys sequences, we performed a phylogenetic analysis of the rRNA, incorporating the consideration of secondary structure. DA - 2001/1/1/ PY - 2001/1/1/ DO - 10.1128/JCM.39.1.90-93.2001 VL - 39 IS - 1 SP - 90-93 J2 - Journal of Clinical Microbiology LA - en OP - SN - 0095-1137 UR - http://dx.doi.org/10.1128/JCM.39.1.90-93.2001 DB - Crossref ER - TY - JOUR TI - Canine Rocky Mountain spotted fever: A retrospective study of 30 cases AU - Gasser, AM AU - Birkenheuer, AJ AU - Breitschwerdt, EB T2 - JOURNAL OF THE AMERICAN ANIMAL HOSPITAL ASSOCIATION AB - Rocky Mountain spotted fever (RMSF) was diagnosed in 30 dogs examined at North Carolina State University, Veterinary Teaching Hospital between 1984 and 1997. Historical, physical examination, and laboratory abnormalities were reviewed. Diagnostic criteria included a four-fold rise in antibody titer to Rickettsia rickettsii (R. rickettsii) (n=15) or a single R. rickettsii antibody titer of 1:1,024 or greater (n=15; when this initial titer was determined one week or more after the onset of clinical signs). Fifteen (50%) dogs were greater than seven years of age, and 13 (43%) dogs were between two and seven years of age. There was no sex predilection. Only five (17%) dogs had a history of known tick exposure. Presumably due to delayed diagnosis, dogs with antibody titers of 1:1,024 or greater at the time of presentation had a higher incidence of more severe neurological dysfunction (e.g., ataxia, hyperesthesia, vestibular disease, and seizures) and cutaneous lesions (e.g., hyperemia, edema, petechiae, ecchymoses, and necrosis). Laboratory findings included anemia, leukocytosis accompanied by toxic granulation of neutrophils, hypoalbuminemia, and coagulation abnormalities; signs were generally more severe in the 15 dogs with R. rickettsii antibody titers of 1:1,024 or greater at the time of presentation. Twelve (40%) dogs in this study were severely thrombocytopenic (less than 75 x10(3) platelets/microl; reference range, 200 to 450 x 10(3)/microl), without clinical evidence of fulminant disseminated intravascular coagulation. In this study, the survival rate following R. rickettsii infection was 100%. DA - 2001/// PY - 2001/// DO - 10.5326/15473317-37-1-41 VL - 37 IS - 1 SP - 41-48 SN - 0587-2871 ER - TY - BOOK TI - Defending animal rights AU - Regan, T. H. CN - HV4711 .R366 2001 DA - 2001/// PY - 2001/// PB - Urbana, IL: University of Illinois Press SN - 025202611X ER - TY - JOUR TI - Semiparametric nonlinear mixed-effects models and their applications - Comment AU - Lin, X. H. AU - Zhang, D. W. T2 - Journal of the American Statistical Association DA - 2001/// PY - 2001/// VL - 96 IS - 456 SP - 1288-1291 ER - TY - JOUR TI - Polymix breeding with parental analysis of progeny: an alternative to full-sib breeding and testing AU - Lambeth, C AU - Lee, BC AU - D O'Malley, AU - Wheeler, N T2 - THEORETICAL AND APPLIED GENETICS DA - 2001/11// PY - 2001/11// DO - 10.1007/s001220100627 VL - 103 IS - 6-7 SP - 930-943 SN - 0040-5752 KW - polymix crossing KW - mating design KW - genetic fingerprinting KW - genetic markers KW - genetic gain ER - TY - JOUR TI - Phylogenetic analyses of amino acid variation in the serpin proteins AU - Atchley, WR AU - Lokot, T AU - Wollenberg, K AU - Dress, A AU - Ragg, H T2 - MOLECULAR BIOLOGY AND EVOLUTION AB - Phylogenetic analyses of 110 serpin protein sequences revealed clades consistent with independent phylogenetic analyses based on exon-intron structure and diagnostic amino acid sites. Trees were estimated by maximum likelihood, neighbor joining, and partial split decomposition using both the BLOSUM 62 and Jones-Taylor-Thornton substitution matrices. Neighbor-joining trees gave results closest to those based on independent analyses using genomic and chromosomal data. The maximum-likelihood trees derived using the quartet puzzling algorithm were very conservative, producing many small clades that separated groups of proteins that other results suggest were related. Independent analyses based on exon-intron structure suggested that a neighbor-joining tree was more accurate than maximum-likelihood trees obtained using the quartet puzzling algorithm. DA - 2001/8// PY - 2001/8// DO - 10.1093/oxfordjournals.molbev.a003936 VL - 18 IS - 8 SP - 1502-1511 SN - 1537-1719 KW - serpins KW - molecular evolution KW - phylogeny KW - protein evolution KW - maximum likelihood KW - neighbor joining ER - TY - JOUR TI - Maize ribosome-inactivating protein inhibits normal development of Aspergillus nidulans and Aspergillus flavus AU - Nielsen, K AU - Payne, GA AU - Boston, RS T2 - MOLECULAR PLANT-MICROBE INTERACTIONS AB - The abundant maize kernel ribosome-inactivating protein 1 (RIP1) was tested for antifungal activity against Aspergillus nidulans and Aspergillus flavus. A microculture assay was developed to monitor fungal growth and development after treatment of conidia with RIP1 or control proteins. A striking decrease in hyphal proliferation was observed when conidia of A. nidulans, a genetically well-characterized nonpathogenic species, were treated with RIP1 protein. Treatment with a RIP1 mutant protein that lacked enzymatic ribosome-inactivating activity caused no observable effects. RIP1 treatment of conidia from the maize pathogen A. flavus resulted in increased hyphal branching. Examination of the branched hyphae after Congo red staining revealed only one growing hyphal tip per conidium. These results indicate that both fungi were affected by RIP1 treatment, but the lysis seen with treatment of A. nidulans was apparently avoided by A. flavus. A developmental time course revealed that both fungal species were affected by RIP1 at the postdivisional growth stage. The inhibitory activity of RIP1 against normal fungal growth is consistent with a biological function to protect the seed from fungal invasion. DA - 2001/2// PY - 2001/2// DO - 10.1094/mpmi.2001.14.2.164 VL - 14 IS - 2 SP - 164-172 SN - 0894-0282 KW - b-32 KW - plant defense KW - seed protein KW - Zea mays L ER - TY - PCOMM TI - Grafting for transgene containment AU - Lev-Yadun, S AU - Sederoff, R DA - 2001/12// PY - 2001/12// DO - 10.1038/nbt1201-1104 SP - 1104-1104 ER - TY - JOUR TI - Experimental infection of cats with Tritrichomonas foetus AU - Gookin, Jody L. AU - Levy, Michael G. AU - Law, J. Mac AU - Papich, Mark G. AU - Poore, Matthew F. AU - Breitschwerdt, Edward B. T2 - American Journal of Veterinary Research AB - To determine whether infection with Tritrichomonas foetus causes diarrhea in specific-pathogen-free or Cryptosporidium coinfected cats.4 cats with subclinical cryptosporidiosis (group 1) and 4 specific-pathogen-free cats (group 2).Cats were infected orogastrically with an axenic culture of T. foetus isolated from a kitten with diarrhea. Direct microscopy and protozoal culture of feces, fecal character, serial colonic mucosal biopsy specimens, and response to treatment with nitazoxanide (NTZ; group 1) or prednisolone (groups 1 and 2) were assessed.Infection with T. foetus persisted in all cats for the entire 203-day study and resulted in diarrhea that resolved after 7 weeks. Group-1 cats had an earlier onset, more severe diarrhea, and increased number of trichomonads on direct fecal examination, compared with group-2 cats. Use of NTZ eliminated shedding of T. foetus and Cryptosporidium oocysts, but diarrhea consisting of trichomonad-containing feces recurred when treatment was discontinued. Prednisolone did not have an effect on infection with T. foetus but resulted in reappearance of Cryptosporidium oocysts in the feces of 2 of 4 cats. During necropsy, T. foetus was isolated from contents of the ileum, cecum, and colon. Tritrichomonas foetus organisms and antigen were detected on surface epithelia and within superficial detritus of the cecal and colonic mucosa.After experimental inoculation in cats, T. foetus organisms colonize the ileum, cecum, and colon, reside in close contact with the epithelium, and are associated with transient diarrhea that is exacerbated by coexisting cryptosporidiosis but not treatment with prednisolone. DA - 2001/11// PY - 2001/11// DO - 10.2460/ajvr.2001.62.1690 VL - 62 IS - 11 SP - 1690-1697 J2 - American Journal of Veterinary Research LA - en OP - SN - 0002-9645 UR - http://dx.doi.org/10.2460/ajvr.2001.62.1690 DB - Crossref ER - TY - JOUR TI - Effect of handling and water stress on water status and rooting of loblolly pine stem cuttings AU - Murthy, R AU - Goldfarb, B T2 - NEW FORESTS DA - 2001/// PY - 2001/// DO - 10.1023/A:1012222207530 VL - 21 IS - 3 SP - 217-230 SN - 0169-4286 KW - Pinus taeda L. KW - rooted cuttings KW - storage KW - vapor pressure deficit KW - vegetative propagation KW - water potential KW - water relations ER - TY - JOUR TI - Characterization of RNAse P holoenzymes from methanococcusjannaschii and methanothermobacter thermoautotrophicus AU - Andrews, A. J. AU - Hall, T. A. AU - Brown, J. W. T2 - Biological Chemistry Hoppe-Seyler DA - 2001/// PY - 2001/// VL - 382 IS - 8 SP - 1171-1177 ER - TY - JOUR TI - A multivalent pairing model of linkage analysis in autotetraploids AU - Wu, S. S. AU - Wu, R. L. AU - Ma, C. X. AU - Zeng, Z. B. AU - Yang, M. C. AU - Casella, G. T2 - Genetics DA - 2001/// PY - 2001/// VL - 159 IS - 3 SP - 1339-1350 ER - TY - JOUR TI - Quantitative trait loci in Drosophila AU - Mackay, TFC T2 - NATURE REVIEWS GENETICS DA - 2001/1// PY - 2001/1// DO - 10.1038/35047544 VL - 2 IS - 1 SP - 11-20 SN - 1471-0064 ER - TY - JOUR TI - Pulping and bleaching of CAD-deficient wood AU - Dimmel, DR AU - MacKay, JJ AU - Althen, EM AU - Parks, C AU - Sederoff, RR T2 - JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY AB - Mutant loblolly pine trees that are deficient in the enzyme cinnamyl alcohol dehydrogenase (CAD) have been obtained through directed breeding. The lignin in the wood of CAD-deficient trees has a different pool of precursors, resulting in high levels of pulping-resistant C-5 linkages. Wood from a 12-year-old CAD-deficient tree has been pulped under soda and kraft conditions in microdigestors. In comparison to a normal 12-year-old loblolly pine, the CAD-deficient wood was much more easily delignified. In addition, the pulp from CAD-deficient wood was as easy to bleach as a control pulp. The high reactivity of CAD-deficient wood may be related to the lignin size and phenolic content. The molecular weight of an isolated milled wood lignin from CAD-deficient pine was ∼35% less than that from a normal pine tree. DA - 2001/// PY - 2001/// DO - 10.1081/WCT-100102651 VL - 21 IS - 1 SP - 1-17 SN - 1532-2319 ER - TY - PCOMM TI - Moribund funding in agricultural research AU - Robertson, G. P. AU - Barry, P. J. AU - Busta, F. F. AU - Collier, R. J. AU - Keen, N. T. AU - Sederoff, R. R. AU - Simpkins, W. W. AU - Stormshak, F. AU - Urban, T. N. AB - The double-digit increases in federal funding for basic research at the National Science Foundation (NSF) and the National Institutes of Health (NIH) for fiscal year 2001 are a welcome development ([1][1]), but does recognition of basic research as the engine that drives technology and economic growth not apply to agriculture? The standard competitive grants program for basic research at the U.S. Department of Agriculture (USDA) began as the National Research Initiative 10 years ago after National Research Council (NRC) reports decried the lack of support for competitive research in the agricultural sciences. The program has outgrown its initiative status, yet it has been stalled for 9 years at a funding level that can only be described as moribund. Whereas support for competitive basic research programs at NSF and NIH combined have grown in constant dollars by 60% since 1992 ([2][2]), funding for the USDA's competitive grants program has decreased 14% in constant dollars since its 1992 appropriation of $100 million. A report from the NRC noted the high quality of National Research Initiative research, its crucial contributions to agricultural productivity and environmental quality, and the more than three dozen studies that have placed the economic rate of return on public investment in food and fiber research at 35 to 60% per year ([3][3]). This is a phenomenal rate of return. New markets, new products, and environmental protection require new ideas, new approaches, and levels of research funding commensurate with the importance that society places on a safe, productive, and environmentally benign food and fiber production system. In 30 years—the approximate time it takes basic research in the public sector to reach marketplace maturity—the world population will have increased by about 3 billion. Will we have funded the basic research necessary to feed and clothe them? 1. [↵][4]1. D. Malakoff , Science 291, 33 (2001) See, for example,. [OpenUrl][5][FREE Full Text][6] 2. [↵][7]American Association for the Advancement of Science, Historical data on federal R&D, FY 1976-2001. Available at . 3. [↵][8]1. National Research Council , National Research Initiative: A Vital Competitive Grants Program in Food, Fiber, and Natural-Resources Research (National Academy Press, Washington, DC, 2000). [1]: #ref-1 [2]: #ref-2 [3]: #ref-3 [4]: #xref-ref-1-1 View reference 1 in text [5]: {openurl}?query=rft.jtitle%253DScience%26rft.stitle%253DScience%26rft.issn%253D0036-8075%26rft.aulast%253DMalakoff%26rft.auinit1%253DD.%26rft.volume%253D291%26rft.issue%253D5501%26rft.spage%253D33%26rft.epage%253D33%26rft.atitle%253D2001%2BU.S.%2BBUDGET%253A%2BRecord%2BYear%2Bfor%2BScience%252C%2BBut%2BCan%2BIt%2BBe%2BRepeated%253F%26rft_id%253Dinfo%253Adoi%252F10.1126%252Fscience.10.1126%252FSCIENCE.291.5501.33%26rft_id%253Dinfo%253Apmid%252F11192000%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [6]: /lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiRlVMTCI7czoxMToiam91cm5hbENvZGUiO3M6Mzoic2NpIjtzOjU6InJlc2lkIjtzOjExOiIyOTEvNTUwMS8zMyI7czo0OiJhdG9tIjtzOjI1OiIvc2NpLzI5MS81NTExLzIwODkuMy5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30= [7]: #xref-ref-2-1 View reference 2 in text [8]: #xref-ref-3-1 View reference 3 in text DA - 2001/// PY - 2001/// DO - 10.1126/science.291.5511.2089c SP - 2089-2090 ER - TY - JOUR TI - Molecular diversity, structure and domestication of grasses AU - Buckler, E. S. AU - Thornsberry, J. M. AU - Kresovich, S. T2 - Genetical Research DA - 2001/// PY - 2001/// VL - 77 IS - 3 SP - 213-218 ER - TY - JOUR TI - Investigation of acid cocatalysis in syntheses of tetra-phenylporphyrin AU - Geier, GR AU - Riggs, JA AU - Lindsey, JS T2 - JOURNAL OF PORPHYRINS AND PHTHALOCYANINES DA - 2001/9// PY - 2001/9// DO - 10.1002/jpp.380.abs VL - 5 IS - 9 SP - 681-690 SN - 1088-4246 KW - acid catalysis KW - cocatalysis KW - porphyrin KW - pyrrole KW - aldehyde ER - TY - JOUR TI - Expression of a chimeric retroviral-lipase mRNA confers enhanced lipolysis in a hibernating mammal AU - Bauer, V. W. AU - Squire, T. L. AU - Lowe, M. E. AU - Andrews, M. T. T2 - American Journal of Physiology DA - 2001/// PY - 2001/// VL - 281 IS - 4 SP - R1186-1192 ER - TY - JOUR TI - A linear two-state model with complex dynamics AU - Elston, TC AU - Kepler, TB T2 - PHYSICS LETTERS A AB - We study the dynamics of a stochastic two-state model in which all forces are linear. While conceptually simple, we show that the behavior of this system is surprisingly complex. The moments of the system undergo a series of bifurcations as either the overall fluctuation rate or the ratio between the two transition rates is varied. The system displays the very counterintuitive behavior in which all its spatial moments diverge in time, and yet the mean time to escape from a region that includes the origin is infinite. Finally, the system displays resonant activation in a particularly transparent way. DA - 2001/2/26/ PY - 2001/2/26/ DO - 10.1016/S0375-9601(01)00052-4 VL - 280 IS - 4 SP - 204-208 SN - 0375-9601 ER -