@article{reading_hiramatsu_sullivan_2011, title={Disparate Binding of Three Types of Vitellogenin to Multiple Forms of Vitellogenin Receptor in White Perch}, volume={84}, ISSN={["1529-7268"]}, DOI={10.1095/biolreprod.110.087981}, abstractNote={Three types of white perch (Morone americana) vitellogenin (VtgAa, VtgAb, and VtgC) were purified, labeled with digoxigenin (DIG), and subjected to Vtg receptor (Vtgr) binding assays in 96-well plates coated with perch ovarian membrane proteins or to ligand blotting procedures. Binding specificity was evaluated by incubating membrane protein preparations with constant amounts of DIG-Vtg tracer (VtgAa, VtgAb, VtgC, or a mixture of VtgAa and VtgAb [VtgAa/b]) alone or in the presence of unlabeled Vtg ligands. At 250-fold excess molar concentration relative to the tracer, VtgAa and VtgAb were each able to displace only approximately 50% of bound DIG-VtgAa/b, but VtgAa/b could fully displace DIG-VtgAa and DIG-VtgAb under the same conditions. Over a broad range of excess molar ratios, unlabeled VtgAa and VtgAb each displaced their respective DIG-Vtg tracer much more effectively than each did the heterologous tracer (DIG-VtgAb and DIG-VtgAa, respectively). Ligand blotting revealed three forms of Vtgr, a large receptor (>212 kDa) that bound only to VtgAa and two smaller receptors (∼116 and ∼110.5 kDa) that bound preferentially to VtgAb. The VtgC did not specifically bind to ovarian membrane proteins in either assay. Collectively, these results indicate the presence of a system of multiple ovarian Vtgrs with disparate binding to the three types of Vtg present in higher-order teleosts (Acanthomorpha). To our knowledge, this is the first report on binding of multiple types of Vtg to multiple forms of Vtgr in any vertebrate.}, number={2}, journal={BIOLOGY OF REPRODUCTION}, author={Reading, Benjamin J. and Hiramatsu, Naoshi and Sullivan, Craig V.}, year={2011}, month={Feb}, pages={392–399} } @misc{reading_hiramatsu_sawaguchi_matsubara_hara_lively_sullivan_2009, title={Conserved and Variant Molecular and Functional Features of Multiple Egg Yolk Precursor Proteins (Vitellogenins) in White Perch (Morone americana) and other Teleosts}, volume={11}, ISSN={["1436-2236"]}, DOI={10.1007/s10126-008-9133-6}, abstractNote={Three complete cDNAs encoding different forms of vitellogenin (Vtg) were isolated from a white perch (Morone americana) liver cDNA library and characterized with respect to immunobiochemical and functional features of the three Vtgs and their product yolk proteins (YPs) in this species and in the congeneric striped bass (Morone saxatilis). The two longest cDNAs encoded Vtgs with a complete suite of yolk protein domains that, based on comparisons with vtg sequences from other species, were categorized as VtgAa and VtgAb using the current nomenclature for multiple teleost Vtgs. The shorter cDNA encoded a Vtg that lacked a phosvitin domain, had a shortened C-terminus, and was categorized as VtgC. Mapping of peptide sequences from the purified Vtgs and their derived YPs to Vtg sequences deduced from the cDNAs definitively identified the white perch VtgAa, VtgAb, and VtgC proteins. Detailed comparisons of the primary structures of each Vtg with partial or complete sequences of Morone yolk proteins or of Vtgs from other fishes revealed conserved and variant structural elements of teleost Vtgs with functional significance, including, as examples, signal peptide cleavage sites, dimerization sites, cathepsin D protease recognition sites, and receptor-binding domains. These comparisons also yielded an interim revision of the classification scheme for multiple teleost Vtgs.}, number={2}, journal={MARINE BIOTECHNOLOGY}, author={Reading, Benjamin J. and Hiramatsu, Naoshi and Sawaguchi, Sayumi and Matsubara, Takahiro and Hara, Akihiko and Lively, Mark O. and Sullivan, Craig V.}, year={2009}, month={Apr}, pages={169–187} } @inproceedings{sawaguchi_ohkuio_amano_hiramatsu_hara_sullivan_matsubara_2008, title={Controlled accumulation of multiple vitellogenins into oocytes during vitellogenesis in the barfin flounder, Verasper moseri}, volume={32}, number={2}, booktitle={Cybium}, author={Sawaguchi, S. and Ohkuio, N. and Amano, H. and Hiramatsu, N. and Hara, A. and Sullivan, C. V. and Matsubara, T.}, year={2008}, pages={262–262} } @inproceedings{reading_hiramatsu_matsubara_hara_sullivan_2008, title={Deduced primary structures of three vitellogenins and specific binding to putative multiple ovarian receptors in white perch (Morone americana)}, volume={32}, number={2}, booktitle={Cybium}, author={Reading, B. J. and Hiramatsu, N. and Matsubara, T. and Hara, A. and Sullivan, C. V.}, year={2008}, pages={159–161} } @inproceedings{hiramatsu_inoue_ideuchi_fujita_amano_matsubara_sullivan_hara_2008, title={Differential production and uptake of dual vitellogenins in Japanese medaka (Oryzias latipes)}, volume={32}, number={2}, booktitle={Cybium}, author={Hiramatsu, N. and Inoue, M. and Ideuchi, H. and Fujita, T. and Amano, H. and Matsubara, T. and Sullivan, C. V. and Hara, A.}, year={2008}, pages={260–260} } @article{davis_visitacion_riley_hiramatsu_sullivan_hirano_grau_2009, title={Effects of o,p '-DDE, heptachlor, and 17 beta-estradiol on vitellogenin gene expression and the growth hormone/insulin-like growth factor-I axis in the tilapia, Oreochromis mossambicus}, volume={149}, ISSN={["1878-1659"]}, DOI={10.1016/j.cbpc.2008.11.007}, abstractNote={Effects of two endocrine disruptors, o,p'-DDE and heptachlor, and 17beta-estradiol (E(2)) on vitellogenin (Vg) and the growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis were examined in male tilapia. In the first experiment, fish were given 5 weekly injections of either E(2), o,p'-DDE or heptachlor (5 microg/g). E(2) treatment increased plasma Vg and hepatic expression of three Vg genes (Vgs A, B, and C) and estrogen receptor alpha (ERalpha), while reducing plasma levels of IGF-I and suppressing the expression of IGF-I, the GH receptor (GHR2) and the putative somatolactin receptor (GHR1). Neither pesticide greatly affected the other parameters examined, except for a significant reduction in expression of GHR2 and increased plasma IGF-I. In the second experiment, fish were given a single injection of o,p'-DDE or heptachlor (100 microg/g), or E(2) (5 microg/g) and sacrificed 5 days post-injection. Treatment with E(2) stimulated expression of all three Vg genes. Both o,p'-DDE and heptachlor increased expression of VgB, whereas only o,p'-DDE increased VgA expression. There was no effect of o,p'-DDE or heptachlor on VgC expression or plasma Vg levels. Treatment with o,p'-DDE and heptachlor as well as E(2) increased ERalpha and ERbeta transcript levels. Similarly, both pesticides increased GHR1 and IGF-I expression, whereas no significant effect of E(2) was observed on GHR1, GHR2 or IGF-I expression. These results indicate that o,p'-DDE and heptachlor have varying temporal and dose effects on modulation of Vg and the GH/IGF-I axis that are distinct from E(2).}, number={4}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY}, author={Davis, Lori K. and Visitacion, Nancy and Riley, Larry G. and Hiramatsu, Naoshi and Sullivan, Craig V. and Hirano, Tetsuya and Grau, E. Gordon}, year={2009}, month={May}, pages={507–514} } @inproceedings{davis_hiramatsu_sullivan_hirano_grau_2008, title={Estrogen regulation of multiple vitellogenin and estrogen receptor genes and of the growth hormone-insulin like growth factor axis in tilapia}, volume={32}, number={2}, booktitle={Cybium}, author={Davis, L. and Hiramatsu, N. and Sullivan, C. and Hirano, T. and Grau, E. G.}, year={2008}, pages={242–243} } @article{davis_pierce_hiramatsu_sullivan_hirano_grau_2008, title={Gender-specific expression of multiple estrogen receptors, growth hormone receptors, insulin-like growth factors and vitellogenins, and effects of 17 beta-estradiol in the male tilapia (Oreochromis mossambicus)}, volume={156}, ISSN={["0016-6480"]}, DOI={10.1016/j.ygcen.2008.03.002}, abstractNote={Gender-specific expression of estrogen receptors (ERα and ERβ), growth hormone receptors (GHR1 and GHR2), insulin-like growth factors (IGF-I and IGF-II) and three vitellogenins (Vgs A–C) was examined in the liver, gonad, pituitary, and brain of sexually mature male, female, and 17β-estradiol (E2)-treated male tilapia (Oreochromis mossambicus). Reflecting greater growth rate in male tilapia, hepatic expression of GHR1, GHR2, IGF-I and IGF-II as well as plasma IGF-I levels were higher in males than in females, whereas the expression of Vgs A–C and ERα was higher in females. On the other hand, expression of all genes measured was higher in the ovary than in testis. Forty eight hours after E2 injection (5 μg/g) into male fish, hepatic expression of most transcripts measured were altered to levels that were similar to those seen in females. The changes included decreased expression of GHR1, GHR2, IGF-I, and IGF-II, and increased expression of ERα and Vgs A–C. E2 treatment also increased Vg and decreased IGF-I in the plasma. Brain expression of ERα, ERβ, GHR1, and IGF-I was higher in females than in males, whereas pituitary expression of GHR2 and IGF-I was lower in females; only brain expression of GHR1 was increased by E2 treatment. These findings suggest that E2 stimulates Vg production primarily through activation of ERα and down-regulation of the GH/IGF-I axis, thus shifting energy from somatic growth towards vitellogenesis at the level of the liver.}, number={3}, journal={GENERAL AND COMPARATIVE ENDOCRINOLOGY}, author={Davis, Lori K. and Pierce, Andrew L. and Hiramatsu, Naoshi and Sullivan, Craig V. and Hirano, Tetsuya and Grau, E. Gordon}, year={2008}, month={May}, pages={544–551} } @inproceedings{amano_fujita_hiramatsu_kagawa_sawaguchi_matsubara_sullivan_hara_2008, title={Molecular alteration of three forms of vitellogenins and their product yolk proteins during oocyte growth and maturation in grey mullet (Mugil cephalus)}, volume={32}, number={2}, booktitle={Cybium}, author={Amano, H. and Fujita, T. and Hiramatsu, N. and Kagawa, H. and Sawaguchi, S. and Matsubara, T. and Sullivan, C. V. and Hara, A.}, year={2008}, pages={156–158} } @article{amano_fujita_hiramatsu_shimizu_sawaguch_iatsubara_kagawa_nagae_sullivan_hara_2007, title={Egg yolk proteins in gray mullet (Mugil cephalus): Purification and classification of multiple lipovitellins and other vitellogenin-derived yolk proteins and molecular cloning of the parent vitellogenin genes}, volume={307A}, ISSN={["2471-5646"]}, DOI={10.1002/jez.388}, abstractNote={AbstractSeven yolk proteins (YPs), four large lipoproteins (YPs1–4) and three minor yolk components (YPs5–7) including one phosphoprotein (YP7), were purified from extracts of vitellogenic ovaries of grey mullet (Mugil cephalus) by combinations of hydroxylapatite, ion exchange, immunoadsorbent, and gel filtration chromatography. The molecular masses of native YP1, YP2, YP3, and YP4 were estimated to be 330, 325, 335, and 570 kDa, respectively. The tertiary structures of YP1, YP2, and YP3 revealed by sodium dodecyl sulfate polyacrylamide gel electrophoresis were typical of teleost lipovitellins (Lvs), consisting of a heavy chain (∼110, ∼99, and ∼97 kDa, respectively) and a light chain (∼30, ∼29, and ∼21.5 kDa, respectively), while YP4 exhibited a heavy chain (∼110 kDa) and two more polypeptide bands (∼70 and ∼54 kDa). Mapping of N‐terminal peptide sequences of the purified YPs to the primary structure of multiple mullet vitellogenins (Vgs) deduced from their respective complete cDNAs, which were cloned and sequenced, conclusively identified YP1, YP2, and YP3 as Lvs derived from mullet VgA, VgB, and VgC, respectively. The fourth YP (YP4) appeared to be a proteolytic variant consisting of Lv and phosvitin components of VgA. Two other YPs (YP5 and YP6) were identified as β′‐components derived from VgA and VgB based on their structures and common, but not identical, antigenicity to salmonid β′‐component, while purified YP7, a phosphoprotein with a high content of serine residues, was identified as a phosvitin derived from VgB. This is the first report, of which we are aware, on purification and molecular classification of three distinct forms of Lv from any oviparous vertebrate. J. Exp. Zool. 307A:324–341, 2007. © 2007 Wiley‐Liss, Inc.}, number={6}, journal={JOURNAL OF EXPERIMENTAL ZOOLOGY PART A-ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY}, author={Amano, Haruna and Fujita, Toshiaki and Hiramatsu, Naoshi and Shimizu, Munetaka and Sawaguch, Sayumi and Iatsubara, Takahiro and Kagawa, Hirohiko and Nagae, Masaki and Sullivan, Craig V. and Hara, Akihiko}, year={2007}, month={Jun}, pages={324–341} } @article{davis_hiramatsu_hiramatsu_reading_matsubara_hara_sullivan_pierce_hirano_grau_2007, title={Induction of three vitellogenins by 17beta-estradiol with concurrent inhibition of the growth hormone-insulin-like growth factor 1 axis in a euryhaline teleost, the tilapia (Oreochromis mossambicus)}, volume={77}, ISSN={["1529-7268"]}, DOI={10.1095/biolreprod.107.060947}, abstractNote={Abstract The objective of the present study was to utilize the male Mozambique tilapia (Oreochromis mossambicus) as a model for examining the molecular mechanisms that mediate the physiological transition between somatic and gonadal growth in female teleost fish, and in vertebrates in general. Partial cDNAs that encode multiple forms of vitellogenin (Vtg), which is the major precursor of yolk proteins, were cloned from estrogen-treated males and utilized to develop real-time quantitative RT-PCR assays, which were supplemented by an assay for Vtg immunoreactivity in the plasma. Alignment analyses of the amino acid sequences deduced from the vtg cDNAs revealed three distinct tilapia Vtgs, which were categorized as Aa-, Ab-, and C-type Vtgs. A single injection of male tilapias with 17beta-estradiol (E2) at 5 μg/g body weight significantly increased the plasma E2 and hepatic levels of all three vtg transcripts within 1 day. Plasma E2 levels declined after 3 days, whereas the plasma Vtg immunoreactivity and hepatic levels of the three vtg transcripts continued to increase. Hepatic expression of the estrogen receptor (esr) 1 gene, but not the esr2 gene, also increased markedly 1 day after E2 injection and remained elevated for 5 days. While plasma growth hormone (Gh) levels were unaffected, hepatic expression of transcripts that encoded the Gh receptor and insulin-like growth factor 1 (Igf1) was suppressed by E2, as were the plasma Igf1 levels. These results clearly suggest a distinct negative interplay between the growth and reproductive axes at the molecular level of key hepatic regulatory pathways involved in the control of energy utilization by gonadal and somatic growth processes.}, number={4}, journal={BIOLOGY OF REPRODUCTION}, author={Davis, Lori K. and Hiramatsu, Naoshi and Hiramatsu, Kaori and Reading, Benjamin J. and Matsubara, Takahiro and Hara, Akihiko and Sullivan, Craig V. and Pierce, Andrew L. and Hirano, Tetsuya and Grau, Gordon}, year={2007}, month={Oct}, pages={614–625} } @article{amano_fujita_hiramatsu_sawaguchi_matsubara_sullivan_hara_2007, title={Purification of multiple vitellogenins in grey mullet (Mugil cephalus)}, volume={152}, ISSN={["1432-1793"]}, DOI={10.1007/s00227-007-0768-z}, abstractNote={Three female specific serum proteins were detected immunologically in the sera of grey mullet (Mugil cephalus) which were named vitellogenin A (VgA), VgB, and VgC, based upon their distinct antigenicity against specific antisera raised against three types of mullet lipovitellins (Lvs). These Vgs were subsequently purified from the serum of estradiol-treated mullet by combining several types of chromatography columns (anion exchanger, hydroxylapatite, immunoadsorbent column, and gel filtration). Purified native VgA, VgB, and VgC exhibited molecular masses of 570, 580, and 335 kDa, respectively. Following, SDS-PAGE, the estimated mass of polypeptide bands evident for VgA and VgB were ∼179 and ∼175 kDa, respectively; VgC appeared to be ∼132 kDa. The two larger Vgs (VgA and VgB) appeared to be phosphorylated, suggesting that these Vgs contain a highly phosphorylated, serine-rich phosvitin (Pv) domain. Furthermore, two discrete Vg-type specific antisera, anti-VgA and anti-VgB, were developed and each generated two precipitin lines against ovary extracts in immunoelectrophoresis, indicating that these Vgs contain additional antigenic yolk protein domains: Lv and β′-component. The small Vg (VgC) appeared to lack a Pv domain because of its low serine content (5.35%) and failure to show positive results in phospho-staining experiments. In conjunction with N-terminal amino acid sequencing analyses of the purified Vgs, our present results have conclusively identified the purified Vg products in grey mullet as typical A-type (VgA), B-type (VgB), and C-type (VgC) Vgs.}, number={6}, journal={MARINE BIOLOGY}, author={Amano, Haruna and Fujita, Toshiaki and Hiramatsu, Naoshi and Sawaguchi, Sayumi and Matsubara, Takahiro and Sullivan, Craig V. and Hara, Akihiko}, year={2007}, month={Nov}, pages={1215–1225} } @article{sawaguchi_kagawa_ohkubo_hiramatsu_sullivan_matsubara_2006, title={Molecular characterization of three forms of vitellogenin and their yolk protein products during oocyte growth and maturation in red seabream (Pagrus major), a marine teleost spawning pelagic eggs}, volume={73}, ISSN={["1098-2795"]}, DOI={10.1002/mrd.20446}, abstractNote={AbstractFull‐length cDNAs encoding three forms of vitellogenin (Vg) were obtained from a liver cDNA library of estrogen‐treated red seabream, Pagrus major. Two of the three Vg sequences had high homology with type‐A and ‐B Vgs (VgA and VgB) of other teleosts. The third red seabream Vg was classified as a type‐C or phosvitinless (Pvl) Vg due to its lack of a phosvitin (Pv) domain. Two Vg preparations (610 and 340 kDa) from blood serum of estradiol‐treated fish were biochemically characterized. Analyses of precursor‐product relationships by examination of N‐terminal amino acid sequences verified cleavage of the 610 kDa Vg into a 540 kDa lipovitellin (Lv) and a 32 kDa β′‐component. Each of these yolk preparations comprising both VgA‐ and VgB‐derived polypeptides. The 340 kDa Vg, which was immunologically verified to be a PvlVg, was accumulated by vitellogenic oocytes with no alterations to its native molecular mass. During oocyte maturation, the VgA‐ and VgB‐derived yolk proteins were differentially processed, presumably to generate a pool of free amino acids for oocyte hydration or for allocation of specific types of nutrients, amino acids, and proteins, to the developing embryo. Conversely, the 340 kDa Vg‐derived yolk protein is unlikely to contribute to oocyte hydration or diffusible nutrients since the molecule underwent only minor proteolytic nicking during oogenesis. The present study elucidates for the first time specific functions of three different forms of Vg and their product yolk proteins in a higher taxonomic group of marine teleosts that spawn pelagic eggs. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.}, number={6}, journal={MOLECULAR REPRODUCTION AND DEVELOPMENT}, author={Sawaguchi, S and Kagawa, H and Ohkubo, N and Hiramatsu, N and Sullivan, CV and Matsubara, T}, year={2006}, month={Jun}, pages={719–736} } @article{hiramatsu_matsubara_fujita_sullivan_hara_2006, title={Multiple piscine vitellogenins: biomarkers of fish exposure to estrogenic endocrine disruptors in aquatic environments}, volume={149}, ISSN={["1432-1793"]}, DOI={10.1007/s00227-005-0214-z}, abstractNote={Vitellogenin (Vg), a major estrogen-inducible yolk precursor protein, has become an important biomarker for assessing the estrogenic potency of chemicals and the exposure of animals to estrogenic contaminants present in aquatic environments. These contaminants, which can disrupt functioning of the vertebrate neuroendocrine system, are known as endocrine disrupting chemicals (EDCs). In general, investigations of the significance of estrogenic EDCs have failed to keep pace with recent developments in our understanding of vitellogenesis in fishes. Recent gene cloning and immunobiochemical analyses have verified the general multiplicity of piscine Vg and led to exploration of the unique roles of yolk proteins derived from different forms of Vg in the processes of oogenesis and embryogenesis. The levels of circulating Vg proteins (or Vg gene transcripts) during oogenesis and their degree of induction by estrogens appear to vary among species and among different types of Vg within species. The kinetics of induction of distinct types of Vg by estrogens in fishes appears to depend on environmental factors (e.g., water temperature and photoperiod), life history stage, and the concentration and type of estrogenic compound. Consideration of these findings will contribute to development of Vg-based bioassays superior to those currently based on the outdated "single Vg" model.}, number={1}, journal={MARINE BIOLOGY}, author={Hiramatsu, N and Matsubara, T and Fujita, T and Sullivan, CV and Hara, A}, year={2006}, month={Apr}, pages={35–47} } @article{fujita_fukada_shimizu_hiramatsu_hara_2005, title={Annual changes in serum levels of two choriogenins and vitellogenin in masu salmon, Oncorhynchus masou}, volume={141}, ISSN={["1879-1107"]}, DOI={10.1016/j.cbpc.2005.03.002}, abstractNote={Annual changes in serum levels of two chorion precursors, choriogenin H (Chg H) and choriogenin L (Chg L), vitellogenin (Vg) and estradiol-17β (E2) were quantified in masu salmon, Oncorhynchus masou, using specific immunoassays. Serum Chg levels were higher than Vg during the previtellogenic growth phase when circulating E2 levels were low (∼0.1 ng/mL), suggesting higher sensitivity of Chg to E2. When oocyte growth shifted to the vitellogenic phase, Vg levels increased and became the most abundant in serum coincident with elevations of E2 and GSI. Chg H, Chg L and Vg peaked 1 month prior to ovulation at 0.61 ± 0.08, 0.98 ± 0.18 and 10.93 ± 3.24 mg/mL, respectively. These results suggest that chorion formation by Chgs occurs prior to vitellogenesis and that the sensitivity of Chgs to low circulating E2 is closely related to the sequential events of oocyte growth.}, number={2}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY}, author={Fujita, T and Fukada, H and Shimizu, M and Hiramatsu, N and Hara, A}, year={2005}, month={Jun}, pages={211–217} } @article{hiramatsu_chapman_lindzey_haynes_sullivan_2004, title={Molecular characterization and expression of vitellogenin receptor from white perch (Morone americana)}, volume={70}, ISSN={["1529-7268"]}, DOI={10.1095/biolreprod.103.023655}, abstractNote={Abstract A full-length (4021 base pair [bp]) cDNA encoding a polypeptide (844 amino acids) with a predicted mass of 93 kDa and other characteristic structural features of a vertebrate vitellogenin receptor (VgR) was isolated from a white perch (Morone americana) ovarian cDNA library. Northern blotting performed using a specific digoxygenin-labeled VgR cDNA probe revealed a distinct ∼4.1 kilobase (kb) hybridization signal in an mRNA preparation obtained from previtellogenic perch ovaries. The deduced amino acid sequence of the perch VgR was 89% and 82% identical, respectively, to that of the tilapia and rainbow trout. Because it possessed an eight-repeat ligand-binding domain (LR8) but lacked an O-linked sugar domain (−), the perch VgR was identified as a non-O-linked form of VgR (LR8−). Unlike the case in other vertebrates investigated, including tilapia and trout, no species of mRNA encoding an O-linked form of VgR (LR8+) could be detected when perch ovarian or liver mRNA reverse transcripts or cDNA libraries were screened by PCR using primer sets flanking the putative O-linked sugar domain. These novel findings call into question the assumptions that an LR8+ splice variant of the VgR always is dominantly present in somatic tissues and exists at lower levels in ovarian tissues to sequester lipoproteins distinct from Vg. A SYBR-green-based real-time reverse transcription-polymerase chain reaction assay was developed and used to quantitatively measure VgR expression in gonadal and somatic tissues, for the first time in any vertebrate. The main site of perch VgR mRNA expression was the ovary and the highest level of VgR mRNA expression was in ovaries whose largest follicles contained previtellogenic oocytes. Expression of VgR mRNA decreased with oocyte growth during vitellogenesis and was very limited in ovulated eggs. These quantitative results verify the concept that growing oocytes must extensively recycle LR8− forms of the VgR.}, number={6}, journal={BIOLOGY OF REPRODUCTION}, author={Hiramatsu, N and Chapman, RW and Lindzey, JK and Haynes, MR and Sullivan, CV}, year={2004}, month={Jun}, pages={1720–1730} } @article{fujita_fukada_shimizu_hiramatsu_hara_2004, title={Quantification of serum levels of precursors to vitelline envelope proteins (choriogenins) and vitellogenin in estrogen treated masu salmon, Oncorhynchus masou}, volume={136}, ISSN={["1095-6840"]}, DOI={10.1016/j.ygcen.2003.12.002}, abstractNote={Previously two precursors to vitelline envelope proteins, choriogenin H (Chg H) and choriogenin L (Chg L), were identified in masu salmon, Oncorhynchus masou, and specific antisera against these two proteins were generated in rabbits. In this study, two methods of immunoassay have been developed using these specific antibodies: single radial immunodiffusion (SRID) and enzyme-linked immunosorbent assay (ELISA). Non-competitive sandwich ELISAs for Chg H and Chg L were designed using digoxigenin-labeled antibodies and purified Chgs as assay components. The working range of the ELISAs was 1-128 and 2-256 ng/ml for Chg H and Chg L, respectively. Using these immunoassays and a chemiluminescent immunoassay for vitellogenin (Vg), the changes in these three estrogen-responsive proteins were measured in the serum of masu salmon after treatment with various doses of estradiol-17beta (E2). The changes in serum levels of Chgs and Vg in male fish differed according to the E2 dose. When fish were given a 5 mg/kg body weight (BW) of E2, Vg was induced to a greater extent than Chgs. By contrast, Chg levels were higher than that of Vg after a 10 microg/kg BW of E2 injection. A similar trend was seen in the response time to exogenous E2. Serum Chgs were induced from 8h after E2 injection and reached a peak of about 5 microg/ml at 24h. Although Vg was not detected until 8h after E2 injection, its levels remained considerably low at around 0.03 microg/ml, even after 24 h. Chg H was more sensitive than was Chg L to 1 microg/kg BW of estrogen: the long-term exposure of fish to E2 showed that Chg H could be induced from a lower dose of E2 than could Chg L. Taken together, these results suggest that the serum levels of Chg H, Chg L, and Vg in masu salmon are regulated by circulating levels of E2.}, number={1}, journal={GENERAL AND COMPARATIVE ENDOCRINOLOGY}, author={Fujita, T and Fukada, H and Shimizu, M and Hiramatsu, N and Hara, A}, year={2004}, month={Mar}, pages={49–57} } @article{donato_hiramatsu_arey_hiramatsu_kennedy_morton_hara_sullivan_2003, title={Atresia in temperate basses: cloning of hatching enzyme (choriolysin) homologues from atretic ovaries}, volume={28}, ISSN={["0920-1742"]}, DOI={10.1023/B:FISH.0000030573.04442.19}, number={1-4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Donato, DM and Hiramatsu, N and Arey, KM and Hiramatsu, K and Kennedy, AM and Morton, CL and Hara, A and Sullivan, CV}, year={2003}, pages={329–330} } @article{fukada_fujiwara_takahashi_hiramatsu_sullivan_hara_2003, title={Carp (Cyprinus carpio) vitellogenin: purification and development of a simultaneous chemiluminescent immunoassay}, volume={134}, ISSN={["1531-4332"]}, DOI={10.1016/S1095-6433(02)00348-3}, abstractNote={Vitellogenin (Vg) was purified from the serum of vitellogenic female carp (Cyprinus carpio) by hydroxylapatite column chromatography and gel filtration. Vg had an apparent molecular mass of 490 kDa and appeared as two bands corresponding to 190 and 156 kDa after SDS-PAGE under reducing conditions. These bands were immunoreacted in Western blotting using antiserum against carp lipovitellin (anti-Lv) which is an egg yolk protein derived from Vg. The amino acid composition of carp Vg was similar to previous reports of cyprinids. The chemiluminescent immunoassay (CLIA) for carp Vg was developed to quantify serum Vg using purified carp Vg and anti-Lv. Its measurable range was from 1.95 to 1000 ng/ml. The dilution curve in the CLIA of vitellogenic female serum was parallel to the standard curve of purified Vg. The coefficient variations of intra- and inter-assay were less than 5%, respectively. Furthermore, the assay had cross-reactivity with the sera of other female cyprinids (crucian carp and Japanese dace). In fish diets-experiments, Vg was detected in all fish in the fish meal containing soybean (20%) group, but was not detected in almost all of the fish in the fish meal-group. This suggests that a soybean based-diet may induce Vg production in the serum of cultivated carp.}, number={3}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY}, author={Fukada, H and Fujiwara, Y and Takahashi, T and Hiramatsu, N and Sullivan, CV and Hara, A}, year={2003}, month={Mar}, pages={615–623} } @article{sullivan_hiramatsu_kennedy_clark_weber_matsubara_hara_2003, title={Induced maturation and spawning: opportunities and applications for research on oogenesis}, volume={28}, ISSN={["1573-5168"]}, DOI={10.1023/B:FISH.0000030635.92568.0a}, number={1-4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Sullivan, CV and Hiramatsu, N and Kennedy, AM and Clark, RW and Weber, GM and Matsubara, T and Hara, A}, year={2003}, pages={481–486} } @article{matsubara_nagae_ohkubo_andoh_sawaguchi_hiramatsu_sullivan_hara_2003, title={Multiple vitellogenins and their unique roles in marine teleosts}, volume={28}, ISSN={["1573-5168"]}, DOI={10.1023/B:FISH.0000030559.71954.37}, number={1-4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Matsubara, T and Nagae, M and Ohkubo, N and Andoh, T and Sawaguchi, S and Hiramatsu, N and Sullivan, CV and Hara, A}, year={2003}, pages={295–299} } @article{hiramatsu_hiramatsu_hara_matsubara_sullivan_2003, title={Multiple vitellogenins in white perch (Morone americana)}, volume={28}, ISSN={["1573-5168"]}, DOI={10.1023/B:FISH.0000030582.66324.6c}, number={1-4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Hiramatsu, K and Hiramatsu, N and Hara, A and Matsubara, T and Sullivan, CV}, year={2003}, pages={347–348} } @article{hiramatsu_hara_matsubara_hiramatsu_sullivan_2003, title={Oocyte growth in temperate basses: multiple forms of vitellogenin and their receptor}, volume={28}, ISSN={["0920-1742"]}, DOI={10.1023/B:FISH.0000030560.79921.10}, number={1-4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Hiramatsu, N and Hara, A and Matsubara, T and Hiramatsu, K and Sullivan, CV}, year={2003}, pages={301–303} } @article{hiramatsu_matsubara_hara_donato_hiramatsu_denslow_sullivan_2002, title={Identification, purification and classification of multiple forms of vitellogenin from white perch (Morone americana)}, volume={26}, ISSN={["1573-5168"]}, DOI={10.1023/B:FISH.0000009266.58556.9a}, number={4}, journal={FISH PHYSIOLOGY AND BIOCHEMISTRY}, author={Hiramatsu, N and Matsubara, T and Hara, A and Donato, DM and Hiramatsu, K and Denslow, ND and Sullivan, CV}, year={2002}, pages={355–370} } @article{fujita_shimizu_hiramatsu_fukada_hara_2002, title={Purification of serum precursor proteins to vitelline envelope (choriogenins) in masu salmon, Oncorhynchus masou}, volume={132}, ISSN={["1096-4959"]}, DOI={10.1016/S1096-4959(02)00075-1}, abstractNote={Three vitelline envelope-related proteins (VERPs), very-high-molecular-weight VERP (vhVERP), high-molecular-weight VERP (hVERP) and low-molecular-weight VERP (lVERP) were purified from female masu salmon serum. The apparent molecular weights of vhVERP, hVERP and lVERP, in their native state, were 520, 88 and 54 kDa, respectively, by gel-filtration chromatography. Very-high-molecular-weight VERP comprises two subunits, corresponding to 175 and 126 kDa. On SDS-PAGE, hVERP and lVERP migrate at 53 and 47 kDa, respectively. Amino acid analysis of vhVERP and hVERP showed that they share a high content of glutamic acid and proline. By contrast, lVERP is rich in glutamic acid and asparatic acid. These features are in good agreement with the amino acid composition of the vitelline envelope. Immuno-biochemical analysis suggested that vhVERP is derived from hVERP by polymerization and/or aggregation. Antibodies against hVERP and lVERP specifically immunostained the vitelline envelope and liver of female masu salmon. In addition, both hVERP and lVERP were induced in the serum of estrogen-treated male fish. Taken together, it is suggested that hVERP and lVERP are homologous molecules with choriogenin H and choriogenin L in medaka, respectively. These results indicate that hVERP and lVERP are precursor proteins to the vitelline envelope (choriogenins) in masu salmon.}, number={3}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY B-BIOCHEMISTRY & MOLECULAR BIOLOGY}, author={Fujita, T and Shimizu, M and Hiramatsu, N and Fukada, H and Hara, A}, year={2002}, month={Jul}, pages={599–610} } @article{hiramatsu_hiramatsu_hirano_hara_2002, title={Vitellogenin-derived yolk proteins in a hybrid sturgeon, bester (Huso huso x Acipencer ruthenus): Identification, characterization and course of proteolysis during embryogenesis}, volume={131}, number={2}, journal={Comparative Biochemistry and Physiology. A, Molecular & Integrative Physiology}, author={Hiramatsu, N. and Hiramatsu, K. and Hirano, K. and Hara, A.}, year={2002}, pages={429–441} } @article{hiramatsu_hara_hiramatsu_fukada_weber_denslow_sullivan_2002, title={Vitellogenin-derived yolk proteins of white perch, Morone americana: Purification, characterization, and vitellogenin-receptor binding}, volume={67}, ISSN={["1529-7268"]}, DOI={10.1095/biolreprod67.2.655}, abstractNote={Abstract The objectives of this study were to 1) purify and characterize vitellogenin-derived yolk proteins of white perch (Morone americana), 2) develop a nonisotopic receptor binding assay for vitellogenin, and 3) identify the yolk protein domains of vitellogenin recognized by the ovarian vitellogenin receptor. Four yolk proteins derived from vitellogenin (YP1, YP2 monomer [YP2m] and dimer [YP2d], and YP3) were isolated from ovaries of vitellogenic perch by selective precipitation, ion exchange chromatography, and gel filtration. The apparent molecular masses of purified YP1, YP2m, and YP2d after gel filtration were 310 kDa, 17 kDa, and 27 kDa, respectively. YP3 appeared in SDS-PAGE as a ∼20-kDa band plus some diffuse smaller bands that could be visualized by staining for phosphoprotein with Coomassie Brilliant Blue complexed with aluminum nitrate. Immunological and biochemical characteristics of YP1, YP2s, and YP3 identified them as white perch lipovitellin, β′-components, and phosvitin, respectively. A novel receptor-binding assay for vitellogenin was developed based on digoxigenin (DIG)-labeled vitellogenin tracer binding to ovarian membrane proteins immobilized in 96-well plates. Lipovitellin from white perch and vitellogenin from perch and other teleosts effectively displaced specifically bound DIG-vitellogenin in the assay, but phosvitin and the β′-component could not, demonstrating for the first time that the lipovitellin domain of teleost vitellogenin mediates its binding to the oocyte receptor. Lipovitellin was less effective than vitellogenin in this regard, suggesting that the remaining yolk protein domains of vitellogenin may interact with its lipovitellin domain to facilitate binding of vitellogenin to its receptor.}, number={2}, journal={BIOLOGY OF REPRODUCTION}, author={Hiramatsu, N and Hara, A and Hiramatsu, K and Fukada, H and Weber, GM and Denslow, ND and Sullivan, CV}, year={2002}, month={Aug}, pages={655–667} }