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413 results on '"Katsu, Yoshinao"'

62. Molecular cloning and immunological analysis of goldfish cyclin A during oocyte maturation

Author

Katsu, Yoshinao, Yamashita, Masakane, Hirai, Toshiaki, Tokumoto, Toshinobu, Kajiura, Hiroko, and Nagahama, Yoshitaka

Subjects
Cloning -- Research, Protein kinases -- Research, Oocytes -- Research, Goldfish -- Research, Cell cycle -- Research, Biological sciences
Abstract

Research indicates different roles for cyclin A-cdc2 kinase and cyclin B-cdc2 kinase during oocyte maturation. Cyclin A cDNA clones were isolated from a library of goldfish oocyte cDNA. Monoclonal antibody from goldfish cyclin A recognized a 47-kDa protein that was not present after the egg was activated. Cyclin A was found in immature oocytes, unlike goldfish cyclin B, and did not show significant changes in protein level during maturation. In mature oocytes, goldfish cyclin A was associated with cdc2 kinase but not with cdk2.

Published
1995

68. Functional distinctions associated with the diversity of sex steroid hormone receptors ESR and AR

Author

Ogino, Yukiko, primary, Tohyama, Saki, additional, Kohno, Satomi, additional, Toyota, Kenji, additional, Yamada, Gen, additional, Yatsu, Ryohei, additional, Kobayashi, Tohru, additional, Tatarazako, Norihisa, additional, Sato, Tomomi, additional, Matsubara, Hajime, additional, Lange, Anke, additional, Tyler, Charles R., additional, Katsu, Yoshinao, additional, Iguchi, Taisen, additional, and Miyagawa, Shinichi, additional

Published
2018
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72. Evolution of the Mineralocorticoid Receptor: Sequence, Structure and Function

Author

Baker, Michael E. and Katsu, Yoshinao

Subjects
medicine.medical_specialty, Aldosterone, biology, Chemistry, medicine.drug_class, Lamprey, Vertebrate, biology.organism_classification, chemistry.chemical_compound, Endocrinology, Mineralocorticoid receptor, Mineralocorticoid, Corticosterone, biology.animal, Internal medicine, medicine, Skate, hormones, hormone substitutes, and hormone antagonists, Hagfish
Abstract

The mineralocorticoid receptor (MR) is descended from a corticoid receptor (CR), which has descendants in lamprey and hagfish, cyclostomes (jawless fish), a taxon that evolved at the base of the vertebrate line. A distinct MR and GR first appear in cartilaginous fishes (Chondrichthyes), such as sharks, skates, rays and chimaeras. Skate MR has a strong response to corticosteroids that are mineralocorticoids and glucocorticoids in humans. The half-maximal responses (EC50s) for skate MR for the mineralocorticoids aldosterone and 11-deoxycorticosterone are 0.07 nM and 0.03 nM, respectively. EC50s for the glucocorticoids cortisol and corticosterone are 1 nM and 0.09 nM, respectively. The physiological mineralocorticoid in ray-finned fish, which do not synthesize aldosterone, is not fully understood because several 3-ketosteroids, including cortisol, 11-deoxycortisol, corticosterone, 11-deoxycorticosterone and progesterone are transcriptional activators of fish MR. Divergence of the MR and GR in terrestrial vertebrates, which synthesize aldosterone, led to increased selectivity of the MR for aldosterone, coupled with a diminished response to cortisol and corticosterone. Here, we combine sequence analysis of the CR and vertebrate MRs and GRs, analysis of crystal structures of human MR and GR and data on transcriptional activation by 3-ketosteroids of wild-type and mutant MRs and GRs to investigate the evolution of selectivity for 3-ketosteroids by the MR in terrestrial vertebrates and ray-finned fish, as well as the basis for binding of some glucocorticoids by human MR and other vertebrate MRs.

Published
2017

73. Oil dispersant Corexit 9500 is weakly estrogenic, but does not skew the sex ratio in Alligator mississippiensis.

Author

McNabb, Nicole A., Bernhard, Melissa C., Brunell, Arnold, Lowers, Russell H., Katsu, Yoshinao, Spyropoulos, Demetri D., and Kohno, Satomi

Subjects
AMERICAN alligator, SEX ratio, EGG incubation, ESTROGEN receptors, OIL spills, NUCLEAR receptors (Biochemistry), BIRD eggs
Abstract

During the Deepwater Horizon oil spill, vast quantities of a chemical dispersant Corexit 9500 were applied in remediation efforts. In addition to the acute toxicity, it is essential to evaluate Corexit further with a broader scope of long‐term sublethal endocrine endpoints. The American alligator (Alligator mississippiensis) is an excellent organism for such an endeavor. It exhibits temperature‐dependent sex determination, in which egg incubation temperatures during a thermosensitive period (TSP) in embryonic development determine the sex of embryos. Estrogen signals play a critical role in this process. For example, a single exposure to exogenous estrogen during the TSP overrides the effects of temperature and leads to skewed sex ratios. At a concentration of 100 ppm, Corexit significantly induced transcriptional activity of both alligator nuclear estrogen receptors 1 and 2 in vitro in reporter gene assays. To investigate the estrogenic effects of Corexit on gonadal development, alligator eggs were exposed to Corexit at environmentally relevant concentrations (0.25, 2.5 and 25 ppm) before the TSP in ovo. Exposure to Corexit at 0.25 and 25 ppm significantly delayed hatching and growth. Corexit exposure at any treatment level did not affect sex ratios or testicular mRNA abundance as measured at 1‐week post‐hatching, suggesting that the combination of Corexit components did not synergize enough to induce ovarian development in ovo. These results point to a need for further investigations on individual and combined components of Corexit to understand better their long‐term effects on the development and reproductive health of alligators and other coastal aquatic wildlife. Corexit 9500, a chemical dispersant used during the Deepwater Horizon oil spill, displayed significant estrogenicity at 100 ppm via both alligator nuclear estrogen receptors 1 and 2 in a transactivation assay in vitro. However, exposure to Corexit at 0.25‐25 ppm in ovo before sex determination did not skew the sex ratio or impact testicular mRNA abundances at 1 week of age. Further investigations will provide a better understanding of potential sex determination‐associated endocrine activities. [ABSTRACT FROM AUTHOR]

Published
2020
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76. Characterization and comparison of transcriptional activities of the retinoid X receptors by various organotin compounds in three prosobranch gastropods; Thais clavigera, Nucella lapillus and Babylonia japonica

Author

Urushitani, Hiroshi, primary, Katsu, Yoshinao, additional, Kagechika, Hiroyuki, additional, Sousa, Ana C.A., additional, Barroso, Carlos M., additional, Ohta, Yasuhiko, additional, Shiraishi, Hiroaki, additional, Iguchi, Taisen, additional, and Horiguchi, Toshihiro, additional

Published
2018
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80. Molecular cloning and characterization of the corticoid receptors from the American alligator

Author

Oka, Kaori, Kohno, Satomi, Urushitani, Hiroshi, Guillette, Louis J., Jr., Ohta, Yasuhiko, Iguchi, Taisen, and Katsu, Yoshinao

Subjects
Transactivation, Alligator, Mineralocorticoid receptor, Glucocorticoid receptor, Cloning
Abstract

Steroid hormones are essential for health in vertebrates. Corticosteroids, for example, have a regulatory role in many physiological functions, such as osmoregulation, respiration, immune responses, stress responses, reproduction, growth, and metabolism. Although extensively studied in mammals and some non-mammalian species, the molecular mechanisms of corticosteroid hormone (glucocorticoids and mineralocorticoids) action are poorly understood in reptiles. Here, we have evaluated hormone receptor-ligand interactions in the American alligator (Alligator mississippiensis), following the isolation of cDNAs encoding a glucocorticoid receptor (GR) and a mineralocorticoid receptor (MR). The full-length alligator GR (aGR) and aMR cDNAs were obtained using 5' and 3' rapid amplification cDNA ends (RACE). The deduced amino acid sequences exhibited high identity to the chicken orthologs (aGR: 83%; aMR: 90%). Using transient transfection assays of mammalian cells, both aGR and aMR proteins displayed corticosteroid-dependent activation of transcription from keto-steroid hormone responsive, murine mammary tumor virus promoters. We further compared the ligand-specifity of human, chicken, Xenopus, and zebrafish GR and MR. We found that the alligator and chicken GR/MR have very similar amino acid sequences, and this translates to very similar ligand specificity. This is the first report of the full-coding regions of a reptilian GR and MR, and the examination of their transactivation by steroid hormones.

Published
2013

82. Cloning and functional characterization of Chondrichthyes, cloudy catshark, Scyliorhinus torazame and whale shark, Rhincodon typus estrogen receptors

Author

Katsu, Yoshinao, Kohno, Satomi, Narita, Haruka, Urushitani, Hiroshi, Yamane, Koudai, Hara, Akihiko, Clauss, Tonya M., Walsh, Michael T., Miyagawa, Shinichi, Guillette, Louis J., and Iguchi, Taisen

Subjects
transactivation, evolution, environmental chemicals, shark, estrogen receptor
Abstract

Sex-steroid hormones are essential for normal reproductive activity in both sexes in all vertebrates. Estrogens are required for ovarian differentiation during a critical developmental stage and promote the growth and differentiation of the female reproductive system following puberty. Recent studies have shown that environmental estrogens influence the developing reproductive system as well as gametogenesis, especially in males. To understand the molecular mechanisms of estrogen actions and to evaluate estrogen receptor ligand interactions in Elasmobranchii, we cloned a single estrogen receptor (ESR) from two shark species, the cloudy catshark (Scyliorhinus torazame) and whale shark (Rhincodon typus) and used an ERE-luciferase reporter assay system to characterize the interaction of these receptors with steroidal and other environmental estrogens. In the transient transfection ERE-luciferase reporter assay system, both shark ESR proteins displayed estrogen-dependent activation of transcription, and shark ESRs were more sensitive to 17β-estradiol compared with other natural and synthetic estrogens. Further, the environmental chemicals, bisphenol A, nonylphenol, octylphenol and DDT could activate both shark ESRs. The assay system provides a tool for future studies examining the receptor-ligand interactions and estrogen disrupting mechanisms in Elasmobranchii.

Published
2010

94. Divergent responsiveness of two isoforms of the estrogen receptor to mixtures of contaminants of emerging concern in four vertebrates.

Author

Kohno, Satomi, Katsu, Yoshinao, Cipoletti, Nicholas, Wang, Lina C., Jorgenson, Zachary G., Miyagawa, Shinichi, and Schoenfuss, Heiko L.

Subjects
ESTROGEN receptors, ENDOCRINE disruptors, AQUATIC biology, BLUEGILL, AMERICAN alligator
Abstract

Abstract: Contaminants of emerging concern (CECs) are ubiquitous in aquatic environments with well‐established endocrine‐disrupting effects. A data matrix of 559 water samples was queried to identify two commonly occurring CECs mixtures in Great Lakes tributaries. One mixture consisted of eight agricultural CECs (AG), while another contained 11 urban CECs (UB). The known estrogenic compounds bisphenol A, estrone and nonylphenol were present in both mixtures. According to the EPA Tox21 in ToxCast database, AG and UB mixture at an environmentally relevant concentration were estimated to account for 6.5% and 3.4% estrogenicity of the model endocrine disruptor estradiol‐17β, respectively. Two isoforms of the estrogen receptor (Esr1 and ‐2, former Erα and Erβ) cloned from fathead minnow, bluegill sunfish, American alligator and human, responded differently to AG and UB mixtures. Human and bluegill Esr1 were the most sensitive to AG and UB mixtures, respectively. Fathead minnow Esr1 and Esr2b were the least sensitive to 10× AG and UB in estrogen dose equivalents, respectively. Even at environmentally documented concentrations, UB significantly activated bluegill Esr1. Moreover, 100× concentrated UB hyperstimulated fathead minnow Esr1 beyond the maximum induction of estradiol‐17β. These results indicate that efficacious receptors and species differ in their response to CEC mixtures. Furthermore, estrogenicity may be present in some CECs not previously considered estrogenic, or, alternatively, estrogenicity of a mixture may be enhanced through chemical interactions. Our study highlights the need for further studies of CECs utilizing a variety of receptors cloned from diverse species. [ABSTRACT FROM AUTHOR]

Published
2018
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96. Understanding the Molecular Basis for Differences in Responses of Fish Estrogen Receptor Subtypes to Environmental Estrogens

Author

Tohyama, Saki, primary, Miyagawa, Shinichi, additional, Lange, Anke, additional, Ogino, Yukiko, additional, Mizutani, Takeshi, additional, Tatarazako, Norihisa, additional, Katsu, Yoshinao, additional, Ihara, Masaru, additional, Tanaka, Hiroaki, additional, Ishibashi, Hiroshi, additional, Kobayashi, Tohru, additional, Tyler, Charles R., additional, and Iguchi, Taisen, additional

Published
2015
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