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Slaby S, Duflot A, Zapater C, Gómez A, Couteau J, Maillet G, Knigge T, Pinto PIS, Monsinjon T. The Dicentrarchus labrax estrogen screen test: a relevant tool to screen estrogen-like endocrine disrupting chemicals in the aquatic environment. CHEMOSPHERE 2024:142601. [PMID: 38880263 DOI: 10.1016/j.chemosphere.2024.142601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Revised: 05/20/2024] [Accepted: 06/11/2024] [Indexed: 06/18/2024]
Abstract
In response to the need for the diversification of regulatory bioassays to screen estrogen-like endocrine disrupting chemical (EEDC) in the environment, we propose the use of a reporter gene assay involving all nuclear estrogen receptors from Dicentrarchus labrax (i.e., sbEsr1, sbEsr2a, or sbEsr2b). Named DLES test (D. labrax estrogen screen), it aims at complementing existing standardized in vitro tests by implementing more estrogen receptors notably those that do not originate from humans. Positive responses were obtained with all three estrogen receptors, and-consistently with observations from other species-variations in sensitivity to E2 were measured. Sensitivity and EC50 values could be classified as follows: sbEsr2b < sbEsr2a < sbEsr1. The pharmacological characterization with a human estrogen receptor antagonist (fulvestrant) successfully validated the specific involvement of each sbEsr and evidenced the capacity of the DLES test to highlight antagonist interactions. The DLES test was applied to WWTP contaminant extracts. A positive response was detected in the inflow sample in accordance with the YES test, but not in the outflow sample. Notwithstanding, the DLES test (sbEsr2b) exhibited greater sensitivity for the screening of those samples. This study demonstrates the need for more comprehensive testing including representatives of marine species for a better detection of EEDCs. The DLES test appears as a pertinent tool to predict adverse effects and to widen the scope of screening and hazard assessment of EEDCs in the environment.
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Affiliation(s)
- Sylvain Slaby
- Normandie Univ, UNILEHAVRE, FR CNRS 3730 SCALE, UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), Le Havre, France.
| | - Aurélie Duflot
- Normandie Univ, UNILEHAVRE, FR CNRS 3730 SCALE, UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), Le Havre, France.
| | - Cinta Zapater
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellon, Spain.
| | - Ana Gómez
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellon, Spain.
| | | | | | - Thomas Knigge
- Normandie Univ, UNILEHAVRE, FR CNRS 3730 SCALE, UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), Le Havre, France.
| | - Patrícia I S Pinto
- Laboratory of Comparative Endocrinology and Integrative Biology, Centre of Marine Sciences (CCMAR), Faro, Portugal.
| | - Tiphaine Monsinjon
- Normandie Univ, UNILEHAVRE, FR CNRS 3730 SCALE, UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), Le Havre, France.
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El-Zaeem SY, El-Hanafy A, El-Dahhar AA, Elmaghraby AM, Ghanem SF, Hendy AM. A Novel Investigation for Early Sex Determination in Alive Adult European Seabass (Dicentrarchus labrax) Using cyp19a1a, dmrt1a, and dmrt1b Genes Expression in Tail Fin tissues. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2024; 26:423-431. [PMID: 38649627 PMCID: PMC11178569 DOI: 10.1007/s10126-024-10313-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 04/09/2024] [Indexed: 04/25/2024]
Abstract
This study is the first investigation for using sex-related gene expression in tail fin tissues of seabass as early sex determination without killing the fish. The European seabass (Dicentrarchus labrax) is gonochoristic and lacks distinguishable sex chromosomes, so, sex determination is referred to molecular actions for some sex-related genes on autosomal chromosomes which are well known such as cyp19a1a, dmrt1a, and dmrt1b genes which play crucial role in gonads development and sex differentiation. cyp19a1a is expressed highly in females for ovarian development and dmrt1a and dmrt1b are for testis development in males. In this study, we evaluated the difference in the gene expression levels of studied genes by qPCR in tail fins and gonads. We then performed discriminant analysis (DA) using morphometric traits and studied gene expression parameters as predictor tools for fish sex. The results revealed that cyp19a1a gene expression was significantly higher in future females' gonads and tail fins (p ≥ 0.05). Statistically, cyp19a1a gene expression was the best parameter to discriminate sex even the hit rate of any other variable by itself could not correctly classify 100% of the fish sex except when it was used in combination with cyp19a1a. In contrast, Dmrt1a gene expression was higher in males than females but there were difficulties in analyzing dmrt1a and dmrt1b expressions in the tail because levels were low. So, it could be used in future research to differentiate and determine the sex of adult fish using the cyp19a1a gene expression marker without killing or sacrificing fish.
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Affiliation(s)
- Samy Y El-Zaeem
- Animal and Fish Production Department, Faculty of Agriculture - Saba-Basha, Alexandria University, Alexandria, Egypt.
| | - Amr El-Hanafy
- Nucleic Acids Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications, Alexandria, Egypt
| | - Alaa A El-Dahhar
- Animal and Fish Production Department, Faculty of Agriculture - Saba-Basha, Alexandria University, Alexandria, Egypt
| | - Ayaat M Elmaghraby
- Nucleic Acids Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications, Alexandria, Egypt
- Faculty of Health Sciences Technology, Borg Al-Arab Technological University, Alexandria, Egypt
| | - Sara F Ghanem
- National Institute of Oceanography and Fisheries, NIOF, Alexandria, Egypt
| | - Amany M Hendy
- Animal and Fish Production Department, Faculty of Agriculture - Saba-Basha, Alexandria University, Alexandria, Egypt.
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3
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Zapater C, Moreira C, Knigge T, Monsinjon T, Gómez A, Pinto PIS. Evolutionary history and functional characterization of duplicated G protein-coupled estrogen receptors in European sea bass. J Steroid Biochem Mol Biol 2024; 236:106423. [PMID: 37939740 DOI: 10.1016/j.jsbmb.2023.106423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 10/29/2023] [Accepted: 11/05/2023] [Indexed: 11/10/2023]
Abstract
Across vertebrates, the numerous estrogenic functions are mainly mediated by nuclear and membrane receptors, including the G protein-coupled estrogen receptor (GPER) that has been mostly associated with rapid non-genomic responses. Although Gper-mediated signalling has been characterized in only few fish species, Gpers in fish appear to present more mechanistic functionalities as those of mammals due to additional gene duplicates. In this study, we ran a thorough investigation of the fish Gper evolutionary history in light of available genomes, we carried out the functional characterization of the two gper gene duplicates of European sea bass (Dicentrarchus labrax) using luciferase reporter gene transactivation assays, validated it with natural and synthetic estrogen agonists/antagonists and applied it to other chemicals of aquaculture and ecotoxicological interest. Phylogenetic and synteny analyses of fish gper1 and gper1-like genes suggest their duplication may have not resulted from the teleost-specific whole genome duplication. We confirmed that both sbsGper isoforms activate the cAMP signalling pathway and respond differentially to distinct estrogenic compounds. Therefore, as observed for nuclear estrogen receptors, both sbsGpers duplicates retain estrogenic activity although they differ in their specificity and potency (Gper1 being more potent and more specific than Gper1-like), suggesting a more conserved role for Gper1 than for Gper1-like. In addition, Gpers were able to respond to estrogenic environmental pollutants known to interfere with estrogen signalling, such as the phytoestrogen genistein and the anti-depressant fluoxetine, a point that can be taken into account in aquatic environment pollution screenings and chemical risk assessment, complementing previous assays for sea bass nuclear estrogen receptors.
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Affiliation(s)
- Cinta Zapater
- Instituto de Acuicultura Torre de la Sal, CSIC, 12595 Torre de la Sal, Castellón, Spain.
| | - Catarina Moreira
- UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, F-76600 Le Havre, France.
| | - Thomas Knigge
- UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, F-76600 Le Havre, France.
| | - Tiphaine Monsinjon
- UMR-I 02 Environmental Stress and Aquatic Biomonitoring (SEBIO), University of Le Havre Normandy, F-76600 Le Havre, France.
| | - Ana Gómez
- Instituto de Acuicultura Torre de la Sal, CSIC, 12595 Torre de la Sal, Castellón, Spain.
| | - Patrícia I S Pinto
- Centro de Ciências do Mar (CCMAR), Universidade do Algarve, 8005-139 Faro, Portugal.
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4
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Li X, Brighton Ndandala C, Zhou Q, Huang C, Li G, Chen H. Molecular cloning of estrogen receptor and its function on vitellogenesis in pompano (Trachinotus ovatus). Gen Comp Endocrinol 2024; 346:114403. [PMID: 37923147 DOI: 10.1016/j.ygcen.2023.114403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 10/22/2023] [Accepted: 10/31/2023] [Indexed: 11/07/2023]
Abstract
Estrogen receptors (ERs) play a critical role in vitellogenesis (Vtgs). However, the contribution of each ER for the regulation of vtgs expression was not analyzed clearly in teleosts. In the present study, three ers isoforms (erα, erβ1, and erβ2) were cloned in pompano (Trachinotus ovatus). Real-time PCR and enzyme-linked immunosorbent assay (ELISA) was used to detect the effects of 17β-estradiol (E2) on ERs and Vtgs in the liver of pompano. In vivo injection experiments showed that E2 significantly increased the expressions of ers and vtgs. ER broad spectrum antagonist Fulvestrant significantly attenuated the E2- induced up-regulation of ers and vtgs in a dose-dependent manner. ERα antagonist Methyl-piperidino pyrazole (MPP) significantly attenuated the up-regulation of erα, erβ2, vtg-B and vtg-C, and promoted the expressions of erβ1 and vtg-A. ERβ antagonist Cyclofenil significantly inhibited the expressions of erβ1, erβ2, vtg-A and vtg-C, and promoted the expressions of erα and vtg-B. In addition, E2 significantly increased the protein level of Vtg, while Fulvestrant, MPP and Cyclofenil significantly inhibited the protein level of Vtg in a dose-dependent manner. Our results indicate that E2 may regulate the expression of each vtg with different subtypes of ERs, and shows a distinct compensatory expression effect on the regulation for ers and vtgs, which provides a theoretical basis for reproductive endocrinology study in pompano.
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Affiliation(s)
- Xiaomeng Li
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China; Key Laboratory of Utilization and Conservation for Tropical Marine Bioresources of Ministry of Education, Hainan Key Laboratory for Conservation and Utilization of Tropical Marine Fishery Resources, Yazhou Bay Innovation Institute, Hainan Tropical Ocean University, Sanya 572022, China
| | - Charles Brighton Ndandala
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang 524025, China
| | - Qi Zhou
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China
| | - Chunyan Huang
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China
| | - Guangli Li
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China
| | - Huapu Chen
- Guangdong Research Center on Reproductive Control and Breeding Technology of Indigenous Valuable Fish Species, Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524088, China; Key Laboratory of Utilization and Conservation for Tropical Marine Bioresources of Ministry of Education, Hainan Key Laboratory for Conservation and Utilization of Tropical Marine Fishery Resources, Yazhou Bay Innovation Institute, Hainan Tropical Ocean University, Sanya 572022, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang 524025, China.
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Soloperto S, Olivier S, Poret A, Minier C, Halm-Lemeille MP, Jozet-Alves C, Aroua S. Effects of 17α-ethinylestradiol on the neuroendocrine gonadotropic system and behavior of European sea bass larvae ( Dicentrarchus labrax). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2023; 86:198-215. [PMID: 36803253 DOI: 10.1080/15287394.2023.2177781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The widespread use of 17α-ethinylestradiol (EE2), and other estrogenic endocrine disruptors, results in a continuous release of estrogenic compounds into aquatic environments. Xenoestrogens may interfere with the neuroendocrine system of aquatic organisms and may produce various adverse effects. The aim of the present study was to expose European sea bass larvae (Dicentrarchus labrax) to EE2 (0.5 and 50 nM) for 8 d and determine the expression levels of brain aromatase (cyp19a1b), gonadotropin-releasing hormones (gnrh1, gnrh2, gnrh3), kisspeptins (kiss1, kiss2) and estrogen receptors (esr1, esr2a, esr2b, gpera, gperb). Growth and behavior of larvae as evidenced by locomotor activity and anxiety-like behaviors were measured 8 d after EE2 treatment and a depuration period of 20 d. Exposure to 0.5 nM EE2 induced a significant increase in cyp19a1b expression levels, while upregulation of gnrh2, kiss1, and cyp19a1b expression was noted after 8 d at 50 nM EE2. Standard length at the end of the exposure phase was significantly lower in larvae exposed to 50 nM EE2 than in control; however, this effect was no longer observed after the depuration phase. The upregulation of gnrh2, kiss1, and cyp19a1b expression levels was found in conjunction with elevation in locomotor activity and anxiety-like behaviors in larvae. Behavioral alterations were still detected at the end of the depuration phase. Evidence indicates that the long-lasting effects of EE2 on behavior might impact normal development and subsequent fitness of exposed fish.
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Affiliation(s)
- S Soloperto
- Normandie Univ, UNIHAVRE, Le Havre Cedex, France
| | - S Olivier
- Normandie Univ, UNIHAVRE, Le Havre Cedex, France
| | - A Poret
- Normandie Univ, UNIHAVRE, Le Havre Cedex, France
| | - C Minier
- Normandie Univ, UNIHAVRE, Le Havre Cedex, France
| | - M P Halm-Lemeille
- Ifremer Port-en-Bessin, LaboratoireEnvironnement Ressources de Normandie, Port-en-Bessin, France
| | - C Jozet-Alves
- Normandie Univ, Unicaen, CNRS, Caen, France
- Univ Rennes, CNRS, Rennes, France
| | - S Aroua
- Normandie Univ, UNIHAVRE, Le Havre Cedex, France
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6
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Alward BA, Hoadley AP, Jackson LR, Lopez MS. Genetic dissection of steroid-hormone modulated social behavior: Novel paralogous genes are a boon for discovery. Horm Behav 2023; 147:105295. [PMID: 36502603 PMCID: PMC9839648 DOI: 10.1016/j.yhbeh.2022.105295] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/23/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022]
Abstract
Research across species has led to important discoveries on the functions of steroid hormones in the regulation of behavior. However, like in many fields, advancements in transgenic and mutagenic technology allowed mice to become the premier genetic model for conducting many experiments to understand how steroids control social behavior. Since there has been a general lack of parallel methodological developments in other species, many of the findings cannot be generalized. This is especially the case for teleost fish, in which a whole-genome duplication produced novel paralogs for key steroid hormone signaling genes. In this review, we summarize technical advancements over the history of the field of neuroendocrinology that have led to important insights in our understanding of the control of social behavior by steroids. We demonstrate that early mouse genetic models to understand these mechanisms suffered from several issues that were remedied by more precise transgenic technological advancements. We then highlight the importance of CRISPR/Cas9 gene editing tools that will in time bridge the gap between mice and non-traditional model species for understanding principles of steroid hormone action in the modulation of social behavior. We specifically highlight the role of teleost fish in bridging this gap because they are 1) highly genetically tractable and 2) provide a novel advantage in achieving precise genetic control. The field of neuroendocrinology is entering a new "gene editing revolution" that will lead to novel discoveries about the roles of steroid hormones in the regulation and evolutionary trajectories of social behavior.
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Affiliation(s)
- Beau A Alward
- University of Houston, Department of Psychology, United States of America; University of Houston, Department of Biology and Biochemistry, United States of America.
| | - Andrew P Hoadley
- University of Houston, Department of Psychology, United States of America
| | - Lillian R Jackson
- University of Houston, Department of Psychology, United States of America
| | - Mariana S Lopez
- University of Houston, Department of Psychology, United States of America
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7
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Nagata J, Mushirobira Y, Nishimiya O, Yamaguchi Y, Fujita T, Hiramatsu N, Hara A, Todo T. Hepatic estrogen-responsive genes relating to oogenesis in cutthroat trout (Oncorhynchus clarki): The transcriptional induction in primary cultured hepatocytes and the in vitro promoter transactivation in responses to estradiol-17β. Gen Comp Endocrinol 2021; 310:113812. [PMID: 33992640 DOI: 10.1016/j.ygcen.2021.113812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 04/28/2021] [Accepted: 05/10/2021] [Indexed: 12/23/2022]
Abstract
Estradiol-17β (E2) regulates transcription of estrogen-responsive genes via estrogen receptors (Esr). In many teleost species, choriogenin (chg), vitellogenin (vtg) and esr genes are transactivated by E2 in the liver. This study aimed i) to compare expression properties of all subtypes of these genes (chg: chgHα, chgHβ, chgL; vtg: vtgAs, vtgC; esr: esr1a, esr1b, esr2a, esr2b) in response to estrogen stimulation, and ii) to confirm how each of four Esr subtypes is involved in the transcriptional regulation of these estrogen-responsive genes in cutthroat trout hepatocytes. In hepatocytes in primary culture, all chg and vtg subtype mRNA levels, and those of esr1a, were increased by E2 treatment (10-6 M) at 24 and 72 h post initiation (hpi), but esr1b, esr2a and esr2b mRNA levels were not. Treatment of hepatocytes with various concentrations of E2 (10-11-10-6 M) induced dose-dependent increases in the levels of all chg and vtg subtype mRNAs at 24 and 72 hpi. At both time points, the lowest dose that induced a significant increase in the expression levels of mRNAs (LOEC) for E2 differed among the genes; LOECs were estimated as 10-11 M for chgHα at 24 hpi, as 10-9 M for vtgC at 72 hpi, and as 10-10 M for other mRNAs at both 24 and 72 hpi. Meanwhile, the levels of esr1a mRNA exhibited a dose-dependent increase at 24 and 72 hpi, but the LOEC shifted from 10-9 M at 24 hpi to 10-7 M at 72 hpi because of a decrease in mRNA levels at treatment groups exposed to high concentrations of E2. All Esr subtypes transactivated chg, vtg and esr1a promoters in the presence of E2 in vitro. The activation levels indicated that promoter activity of chgHα ≥ vtgAs > chgHβ > chgL ≥ vtgC ≥ esr1a when mediated by Esr1a, chgHβ > chgHα > chgHL > vtgAs ≥ vtgC ≥ esr1a by Esr1b, chgHβ ≥ chgL > chgHα ≥ vtgAs > vtgC > esr1a by Esr2a, and chgHβ ≥ chgHα ≥ vtgAs > chgL ≥ vtgC > esr1a by Esr2b. Collectively, different Esr subtypes were distinctly different in their ability to transactivate estrogen-responsive target genes, resulting in differential expression of chg, vtg and esr1a genes in the estrogen-exposed hepatocytes.
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Affiliation(s)
- Jun Nagata
- Division of Marine Life Science, Faculty of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan.
| | - Yuji Mushirobira
- Institute for East China Sea Research, Organization for Marine Science and Technology, Nagasaki University, 1551-7 Taira, Nagasaki 851-2213, Japan
| | - Osamu Nishimiya
- South Ehime Fisheries Research Center, Ehime University, 25-1 Uchidomari, Ainan, Ehime 798-4206, Japan
| | - You Yamaguchi
- Division of Marine Life Science, Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
| | - Toshiaki Fujita
- Faculty of Engineering, Hachinohe Institute of Technology, 88-1 Obiraki, Myo, Hachinohe, Aomori 031-8501, Japan
| | - Naoshi Hiramatsu
- Division of Marine Life Science, Faculty of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
| | - Akihiko Hara
- Division of Marine Life Science, Faculty of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
| | - Takashi Todo
- Division of Marine Life Science, Faculty of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
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Prucha MS, Martyniuk CJ, Doperalski NJ, Kroll KJ, Barber DS, Denslow ND. Steroidogenic acute regulatory protein transcription is regulated by estrogen receptor signaling in largemouth bass ovary. Gen Comp Endocrinol 2020; 286:113300. [PMID: 31678557 PMCID: PMC6993601 DOI: 10.1016/j.ygcen.2019.113300] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 10/08/2019] [Accepted: 10/09/2019] [Indexed: 02/07/2023]
Abstract
Estrogenic contaminants in the environment are linked to the occurrence of reproductive abnormalities in many aquatic species, including largemouth bass (Micropterus salmoides; LMB). Previous work has shown that many different types of xenoestrogens regulate expression of the Steroidogenic Acute Regulatory protein (StAR), a cholesterol-transporting protein vital to steroid hormone biosynthesis; however, the regulatory mechanisms of StAR are incompletely characterized in fish. To learn more about endogenous expression patterns of StAR in the ovary, LMB were collected from the St. John's River (Florida, USA) over an entire breeding season to investigate StAR expression. Plasma 17β-estradiol (E2) and StAR mRNA levels were positively correlated in females, and StAR mRNA levels displayed ~ 100-fold increase between primary oocyte growth stages and final maturation. To further study the regulation of StAR, female LMB in the laboratory were fed at ≃2% of their weight on a diet laden with 17α-ethinylestradiol (EE2, 70 or 200 ng EE2 per gram feed). Diets were designed to achieve a physiologically-relevant exposure to EE2, and StAR expression was assessed in vivo. We observed a dose-dependent suppression of StAR mRNA levels, however both diets led to high, pharmacological levels in the blood and do not represent normal physiological ranges of estrogens. In the 200 ng EE2/gm feed group, ovarian StAR mRNA levels were suppressed to approximately 5% of that of the LMB control group. These investigations suggest that LMB StAR increases in expression during oocyte maturation and that it is suppressed by E2 feedback when estrogen levels are high, through the HPG axis. A 2.9 kb segment of the LMB StAR promoter was examined for putative E2 response elements using in silico software, and a putative estrogen receptor binding element (ERE/-1745) was predicted in the promoter. The functionality of the ERE was examined using MA-10 mouse Leydig cells transfected with the LMB StAR promoter. Estrogen receptor (ER) interaction with ERE/-1745 was evaluated under basal and human chorionic gonadotropin (hCG)-treated conditions in the presence and absence of E2. Chromatin immunoprecipitation (ChIP) experiments revealed that ESR1 binding to the promoter was enriched under basal conditions and E2 exposure elicited an increase in enrichment (4-fold) above that observed under basal conditions. ESR2 was not strongly enriched at the ERE/-1745 site, suggesting that StAR may be preferentially regulated by LMB estrogen receptor 1 (esr1). Taken together, these different experiments provide evidence that LMB StAR is under the control of estrogens and that ESR1 binds directly to the LMB StAR promoter in an E2-responsive manner.
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Affiliation(s)
- Melinda S Prucha
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States
| | - Christopher J Martyniuk
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States
| | - Nicholas J Doperalski
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States
| | - Kevin J Kroll
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States
| | - David S Barber
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States
| | - Nancy D Denslow
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, United States.
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9
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Cabas I, Chaves-Pozo E, Mulero V, García-Ayala A. Role of estrogens in fish immunity with special emphasis on GPER1. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 89:102-110. [PMID: 30092317 DOI: 10.1016/j.dci.2018.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/03/2018] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
It is well accepted that estrogens, the primary female sex hormones, play a key role in modulating different aspects of the immune response. Moreover, estrogens have been linked with the sexual dimorphism observed in some immune disorders, such as chronic inflammatory and autoimmune diseases. Nevertheless, their effects are often controversial and depend on several factors, such as the pool of estrogen receptors (ERs) involved in the response. Their classical mode of action is through nuclear ERs, which act as transcription factors, promoting the regulation of target genes. However, it has long been noted that some of the estrogen-mediated effects cannot be explained by these classical receptors, since they are rapid and mediated by non-genomic signaling pathways. Hence, the interest in membrane ERs, especially in G protein-coupled estrogen receptor 1 (GPER1), has grown in recent years. Although the presence of nuclear ERs, and ER signaling, in immune cells in mammals and fish has been well documented, information on membrane ERs is much scarcer. In this context, the present manuscript aims to review our knowledge concerning the effect of estrogens on fish immunity, with special emphasis on GPER1. For example, the numerous tools developed over recent years allowed us to report for the first time that the regulation of fish granulocyte functions by estrogens through GPER1 predates the split of fish and tetrapods more than 450 million years ago, pointing to the relevance of estrogens as modulators of the immune responses, and the pivotal role of GPER1 in immunity.
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Affiliation(s)
- Isabel Cabas
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Murcia, Spain.
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Murcia, Spain
| | - Victoriano Mulero
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Murcia, Spain
| | - Alfonsa García-Ayala
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Murcia, Spain
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10
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Zapater C, Molés G, Muñoz I, Pinto PIS, Canario AVM, Gómez A. Differential involvement of the three nuclear estrogen receptors during oogenesis in European sea bass (Dicentrarchus labrax)†. Biol Reprod 2018; 100:757-772. [DOI: 10.1093/biolre/ioy227] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 08/06/2018] [Accepted: 10/25/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Cinta Zapater
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Torre la Sal, Castellón, Spain
| | - Gregorio Molés
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Torre la Sal, Castellón, Spain
| | - Iciar Muñoz
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Torre la Sal, Castellón, Spain
| | - Patricia I S Pinto
- Centre of Marine Sciences (CCMAR), University of Algarve, Gambelas, Faro, Portugal
| | - Adelino V M Canario
- Centre of Marine Sciences (CCMAR), University of Algarve, Gambelas, Faro, Portugal
| | - Ana Gómez
- Department of Fish Physiology and Biotechnology, Instituto de Acuicultura de Torre la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Torre la Sal, Castellón, Spain
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11
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Laing L, Viana J, Dempster E, Uren Webster T, van Aerle R, Mill J, Santos E. Sex-specific transcription and DNA methylation profiles of reproductive and epigenetic associated genes in the gonads and livers of breeding zebrafish. Comp Biochem Physiol A Mol Integr Physiol 2018; 222:16-25. [DOI: 10.1016/j.cbpa.2018.04.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/09/2018] [Accepted: 04/10/2018] [Indexed: 12/19/2022]
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Moreman J, Takesono A, Trznadel M, Winter MJ, Perry A, Wood ME, Rogers NJ, Kudoh T, Tyler CR. Estrogenic Mechanisms and Cardiac Responses Following Early Life Exposure to Bisphenol A (BPA) and Its Metabolite 4-Methyl-2,4-bis( p-hydroxyphenyl)pent-1-ene (MBP) in Zebrafish. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:6656-6665. [PMID: 29738667 DOI: 10.1021/acs.est.8b01095] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Environmental exposure to Bisphenol A (BPA) has been associated with a range of adverse health effects, including on the cardiovascular system in humans. Lack of agreement on its mechanism(s) of action likely stem from comparisons between in vivo and in vitro test systems and potential multiple effects pathways. In rodents, in vivo, metabolic activation of BPA produces 4-methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP), which is reported to be up to 1000 times more potent as an estrogen than BPA. We investigated the estrogenic effects and estrogen receptor signaling pathway(s) of BPA and MBP following early life exposure using a transgenic, estrogen responsive (ERE-TG) zebrafish and a targeted morpholino approach to knockdown the three fish estrogen receptor (ER) subtypes. The functional consequences of BPA exposure on the cardiovascular system of zebrafish larvae were also examined. The heart atrioventricular valves and the bulbus arteriosus were primary target tissues for both BPA and MBP in the ERE-TG zebrafish, and MBP was approximately 1000-fold more potent than BPA as an estrogen in these tissues. Estrogen receptor knockdown with morpholinos indicated that the estrogenic responses in the heart for both BPA and MBP were mediated via an estrogen receptor 1 (esr1) dependent pathway. At the highest BPA concentration tested (2500 μg/L), alterations in the atrial:ventricular beat ratio indicated a functional impact on the heart of 5 days post fertilization (dpf) larvae, and there was also a significantly reduced heart rate in these larvae at 14 dpf. Our findings indicate that some of the reported adverse effects on heart function associated with BPA exposure (in mammals) may act through an estrogenic mechanism, but that fish are unlikely to be susceptible to adverse effects on heart development for environmentally relevant exposures.
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Affiliation(s)
- John Moreman
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Aya Takesono
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Maciej Trznadel
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Matthew J Winter
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Alexis Perry
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Mark E Wood
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Nicola J Rogers
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Tetsuhiro Kudoh
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
| | - Charles R Tyler
- Biosciences, College of Life and Environmental Sciences , University of Exeter , Stocker Road , Exeter EX4 4QD , United Kingdom
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Pinto PIS, Andrade AR, Estêvão MD, Alvarado MV, Felip A, Power DM. Duplicated membrane estrogen receptors in the European sea bass (Dicentrarchus labrax): Phylogeny, expression and regulation throughout the reproductive cycle. J Steroid Biochem Mol Biol 2018; 178:234-242. [PMID: 29288793 DOI: 10.1016/j.jsbmb.2017.12.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 12/22/2017] [Accepted: 12/23/2017] [Indexed: 10/18/2022]
Abstract
The numerous estrogen functions reported across vertebrates have been classically explained by their binding to specific transcription factors, the nuclear estrogen receptors (ERs). Rapid non-genomic estrogenic responses have also been recently identified in vertebrates including fish, which can be mediated by membrane receptors such as the G protein-coupled estrogen receptor (Gper). In this study, two genes for Gper, namely gpera and gperb, were identified in the genome of a teleost fish, the European sea bass. Phylogenetic analysis indicated they were most likely retained after the 3R teleost-specific whole genome duplication and raises questions about their function in male and female sea bass. Gpera expression was mainly restricted to brain and pituitary in both sexes while gperb had a widespread tissue distribution with higher expression levels in gill filaments, kidney and head kidney. Both receptors were detected in the hypothalamus and pituitary of both sexes and significant changes in gpers expression were observed throughout the annual reproductive season. In female pituitaries, gpera showed an overall increase in expression throughout the reproductive season while gperb levels remained constant. In the hypothalamus, gpera had a higher expression during vitellogenesis and decreased in fish entering the ovary maturation and ovulation stage, while gperb expression increased at the final atresia stage. In males, gpers expression was constant in the hypothalamus and pituitary throughout the reproductive cycle apart from the mid- to late testicular development stage transition when a significant up-regulation of gpera occurred in the pituitary. The differential sex, seasonal and subtype-specific expression patterns detected for the two novel gper genes in sea bass suggests they may have acquired different and/or complementary roles in mediating estrogens actions in fish, namely on the neuroendocrine control of reproduction.
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Affiliation(s)
| | | | - M Dulce Estêvão
- CCMAR - Centre of Marine Sciences, Faro, Portugal; Escola Superior de Saúde, Universidade do Algarve, Av. Dr. Adelino da Palma Carlos, 8000-510 Faro, Portugal.
| | - M Victoria Alvarado
- CCMAR - Centre of Marine Sciences, Faro, Portugal; Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain.
| | - Alicia Felip
- Institute of Aquaculture Torre de la Sal (IATS-CSIC), Castellón, Spain.
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Diotel N, Charlier TD, Lefebvre d'Hellencourt C, Couret D, Trudeau VL, Nicolau JC, Meilhac O, Kah O, Pellegrini E. Steroid Transport, Local Synthesis, and Signaling within the Brain: Roles in Neurogenesis, Neuroprotection, and Sexual Behaviors. Front Neurosci 2018; 12:84. [PMID: 29515356 PMCID: PMC5826223 DOI: 10.3389/fnins.2018.00084] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/02/2018] [Indexed: 01/18/2023] Open
Abstract
Sex steroid hormones are synthesized from cholesterol and exert pleiotropic effects notably in the central nervous system. Pioneering studies from Baulieu and colleagues have suggested that steroids are also locally-synthesized in the brain. Such steroids, called neurosteroids, can rapidly modulate neuronal excitability and functions, brain plasticity, and behavior. Accumulating data obtained on a wide variety of species demonstrate that neurosteroidogenesis is an evolutionary conserved feature across fish, birds, and mammals. In this review, we will first document neurosteroidogenesis and steroid signaling for estrogens, progestagens, and androgens in the brain of teleost fish, birds, and mammals. We will next consider the effects of sex steroids in homeostatic and regenerative neurogenesis, in neuroprotection, and in sexual behaviors. In a last part, we will discuss the transport of steroids and lipoproteins from the periphery within the brain (and vice-versa) and document their effects on the blood-brain barrier (BBB) permeability and on neuroprotection. We will emphasize the potential interaction between lipoproteins and sex steroids, addressing the beneficial effects of steroids and lipoproteins, particularly HDL-cholesterol, against the breakdown of the BBB reported to occur during brain ischemic stroke. We will consequently highlight the potential anti-inflammatory, anti-oxidant, and neuroprotective properties of sex steroid and lipoproteins, these latest improving cholesterol and steroid ester transport within the brain after insults.
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Affiliation(s)
- Nicolas Diotel
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
| | - Thierry D. Charlier
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Christian Lefebvre d'Hellencourt
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
| | - David Couret
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
- CHU de La Réunion, Saint-Denis, France
| | | | - Joel C. Nicolau
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Olivier Meilhac
- Université de La Réunion, Institut National de la Santé et de la Recherche Médicale, UMR 1188, Diabète athérothrombose Thérapies Réunion Océan Indien, Saint-Denis de La Réunion, France
- CHU de La Réunion, Saint-Denis, France
| | - Olivier Kah
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Elisabeth Pellegrini
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
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15
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Hu P, Meng Z, Jia Y. Molecular characterization and quantification of estrogen receptors in turbot (Scophthalmus maximus). Gen Comp Endocrinol 2018; 257:38-49. [PMID: 28087301 DOI: 10.1016/j.ygcen.2017.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/22/2016] [Accepted: 01/02/2017] [Indexed: 01/11/2023]
Abstract
Estrogens regulate various reproductive processes via estrogen receptor (ER)-mediated signaling pathway in vertebrates. In this study, full-length sequences coding for ERα, ERβ1 and ERβ2 were isolated from female turbot (Scophthalmus maximus) by homology cloning and a strategy based on rapid amplification of cDNA end-polymerase chain reaction (RACE-PCR). The nucleotide and amino acid sequences of turbot ERs showed high homologies with the corresponding sequences of other fish species and significant homology with the Japanese flounder (Paralichthys olivaceus) and the European sea bass (Dicentrarchus labrax). Turbot ERs contained six typical nuclear receptor-characteristic domains and exhibited high evolutionary conservation in the functional domains. Quantitative real-time polymerase chain reaction analysis revealed that the erα and erβ (β1, β2) mRNAs were abundant in the liver and ovary, respectively. Furthermore, hepatic mRNA levels of erα and vitellogenin (vtg) were found increased gradually from pre-vitellogenesis to late-vitellogenesis stages, with the highest values observed at the late-vitellogenesis stage, and then decreased from migratory-nucleus to atresia stages. However, mRNA levels of erα in the ovary remained unchanged during ovarian development. Hepatosomatic index, gonadosomatic index, serum estradiol-17β and the mRNA levels of erβ1 and erβ2 in the ovary manifested results similar to the expression of erα mRNAs in the liver. These findings indicated that ERα is mainly involved in hepatic vitellogenesis, and ERβs may play crucial roles to regulate ovarian development in turbot. Overall, this study improves understanding of the physiological functions of turbot ERs, which will be valuable for fish reproduction and broodstock management.
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Affiliation(s)
- Peng Hu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology, Qingdao 266071, China
| | - Zhen Meng
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology, Qingdao 266071, China
| | - Yudong Jia
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao Key Laboratory for Marine Fish Breeding and Biotechnology, Qingdao 266071, China.
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16
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Lü ZM, Liu W, Liu LQ, Wang TM, Shi HL, Ping HL, Chi CF, Yang JW, Wu CW. Cloning, Characterization, and Expression Profile of Estrogen Receptor in Common Chinese Cuttlefish, Sepiella japonica. ACTA ACUST UNITED AC 2017; 325:181-93. [PMID: 27076436 DOI: 10.1002/jez.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 02/18/2016] [Indexed: 01/08/2023]
Abstract
Sex steroid hormones are widely detected in molluscs and play important roles in sex determination, gonadal tissue maturation, and gametogenesis. Nevertheless, the signaling pathways of sex steroids in cephalopod have not yet been clearly elucidated. In the present study, a full-length sequence encoding the estrogen receptor (ER) was isolated from common Chinese cuttlefish, Sepiella japonica. The sjER cDNA clone was found to contain 1,788 nucleotides including a 1,470 bp open reading frame encoding 489 amino acid (aa) residues. The deduced ER protein consisted of six nuclear receptor characteristic domains. Based on a phylogenetic analysis, the ER DNA-binding domain and ligand-binding domain are highly conserved compared to other mollusc ERs. Highest aa identities were found for sjER with common octopus (Octopus vulgaris) ER (89%) and pacific oyster (Crassostrea gigas) ER (61%). Tissue expression analysis confirmed that sjER was widely distributed among tissues and predominantly expressed in the brain, liver, gonad (testis and ovary), and other accessory sexual gland (nidamental gland). The ER expression was temporally upregulated in the brain, liver, and ovary during the early sexual maturation period in S. japonica, which is coincident with the fluctuation of ovary estradiol content. These suggest that sjER may be involved in regulating the reproductive cycle of S. japonica. A fusion protein transient transfections assay showed that sjER was mainly located in the nucleus, suggesting a possible orthodox working mechanism of S. japonica ER in the nucleus through a ligand-dependent activation of specific gene transcription.
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Affiliation(s)
- Zhen-Ming Lü
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Wan Liu
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Li-Qin Liu
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Tian-Ming Wang
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Hui-Lai Shi
- Marine Fisheries Research Institute of Zhejiang Province, Zhoushan, China
| | - Hong-Ling Ping
- Marine Fisheries Research Institute of Zhejiang Province, Zhoushan, China
| | - Chang-Feng Chi
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Jing-Wen Yang
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
| | - Chang-Wen Wu
- National Engineering Research Center for Facilitated Marine Aquaculture, Marine Science College, Zhejiang Ocean University, Zhoushan, China
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17
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Nishimiya O, Katsu Y, Inagawa H, Hiramatsu N, Todo T, Hara A. Molecular cloning and characterization of hagfish estrogen receptors. J Steroid Biochem Mol Biol 2017; 165:190-201. [PMID: 27287934 DOI: 10.1016/j.jsbmb.2016.06.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 06/05/2016] [Accepted: 06/06/2016] [Indexed: 11/17/2022]
Abstract
One or more distinct forms of the nuclear estrogen receptor (ER) have been isolated from many vertebrates to date. To better understand the molecular evolution of ERs, we cloned and characterized er cDNAs from the inshore hagfish, Eptatretus burgeri, a modern representative of the most primitive vertebrates, the agnathans. Two er cDNAs, er1 and er2, were isolated from the liver of a reproductive female hagfish. A phylogenetic analysis placed hagfish ER1 into a position prior to the divergence of vertebrate ERs. Conversely, hagfish ER2 was placed at the base of the vertebrate ERβ clade. The tissue distribution patterns of both ER subtype mRNAs appeared to be different, suggesting that each subtype has different physiological roles associated with estrogen actions. An estrogen responsive-luciferase reporter assay using mammalian HEK293 cells was used to functionally characterize these hagfish ERs. Both ER proteins displayed estrogen-dependent activation of transcription. These results clearly demonstrate that the hagfish has two functional ER subtypes.
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Affiliation(s)
- Osamu Nishimiya
- Laboratory of Fish Reproductive Physiology and Biochemistry, Division of Marine Life Sciences, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, 041-8611, Japan
| | - Yoshinao Katsu
- Laboratory of Reproductive and Developmental Biology, Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Hiroyuki Inagawa
- Department of Applied Aquabiology, National Fisheries University, Shimonoseki, Yamaguchi 759-6595, Japan
| | - Naoshi Hiramatsu
- Laboratory of Fish Reproductive Physiology and Biochemistry, Division of Marine Life Sciences, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, 041-8611, Japan
| | - Takashi Todo
- Laboratory of Fish Reproductive Physiology and Biochemistry, Division of Marine Life Sciences, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, 041-8611, Japan.
| | - Akihiko Hara
- Laboratory of Fish Reproductive Physiology and Biochemistry, Division of Marine Life Sciences, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, 041-8611, Japan
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Lafont AG, Rousseau K, Tomkiewicz J, Dufour S. Three nuclear and two membrane estrogen receptors in basal teleosts, Anguilla sp.: Identification, evolutionary history and differential expression regulation. Gen Comp Endocrinol 2016; 235:177-191. [PMID: 26654744 DOI: 10.1016/j.ygcen.2015.11.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 11/26/2015] [Accepted: 11/29/2015] [Indexed: 12/17/2022]
Abstract
Estrogens interact with classical intracellular nuclear receptors (ESR), and with G-coupled membrane receptors (GPER). In the eel, we identified three nuclear (ESR1, ESR2a, ESR2b) and two membrane (GPERa, GPERb) estrogen receptors. Duplicated ESR2 and GPER were also retrieved in most extant teleosts. Phylogeny and synteny analyses suggest that they result from teleost whole genome duplication (3R). In contrast to conserved 3R-duplicated ESR2 and GPER, one of 3R-duplicated ESR1 has been lost shortly after teleost emergence. Quantitative PCRs revealed that the five receptors are all widely expressed in the eel, but with differential patterns of tissue expression and regulation. ESR1 only is consistently up-regulated in vivo in female eel BPG-liver axis during induced sexual maturation, and also up-regulated in vitro by estradiol in eel hepatocyte primary cultures. This first comparative study of the five teleost estradiol receptors provides bases for future investigations on differential roles that may have contributed to the conservation of multiple estrogen receptors.
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Affiliation(s)
- Anne-Gaëlle Lafont
- Muséum National d'Histoire Naturelle, Sorbonne Universités, Research Unit BOREA, Biology of Aquatic Organisms and Ecosystems, CNRS 7208, IRD207, UPMC, UCN, Paris, France.
| | - Karine Rousseau
- Muséum National d'Histoire Naturelle, Sorbonne Universités, Research Unit BOREA, Biology of Aquatic Organisms and Ecosystems, CNRS 7208, IRD207, UPMC, UCN, Paris, France
| | - Jonna Tomkiewicz
- Technical University of Denmark, National Institute of Aquatic Resources, Charlottenlund, Denmark
| | - Sylvie Dufour
- Muséum National d'Histoire Naturelle, Sorbonne Universités, Research Unit BOREA, Biology of Aquatic Organisms and Ecosystems, CNRS 7208, IRD207, UPMC, UCN, Paris, France.
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Seemann F, Knigge T, Duflot A, Marie S, Olivier S, Minier C, Monsinjon T. Sensitive periods for 17β-estradiol exposure during immune system development in sea bass head kidney. J Appl Toxicol 2015; 36:815-26. [DOI: 10.1002/jat.3215] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 06/18/2015] [Accepted: 06/19/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Frauke Seemann
- State Key Laboratory in Marine Pollution; City University Hong Kong; Kowloon Hong Kong
| | - Thomas Knigge
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
| | - Aurélie Duflot
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
| | - Sabine Marie
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
| | - Stéphanie Olivier
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
| | - Christophe Minier
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
- Office National de l'Eau et des Milieux Aquatiques (ONEMA); Grabels France
| | - Tiphaine Monsinjon
- UMR-I 02 INERIS-URCA-ULH, Unité Stress Environnementaux et Biosurveillance des milieux aquatiques (SEBIO), SFR SCALE 4116; Université du Havre; Le Havre France
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20
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Valero Y, Sánchez-Hernández M, García-Alcázar A, García-Ayala A, Cuesta A, Chaves-Pozo E. Characterization of the annual regulation of reproductive and immune parameters on the testis of European sea bass. Cell Tissue Res 2015; 362:215-29. [PMID: 25896883 DOI: 10.1007/s00441-015-2172-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 03/18/2015] [Indexed: 11/30/2022]
Abstract
The European sea bass, Dicentrarchus labrax L., is a seasonal gonochoristic species, the males of which are generally mature during their second year of life. It has been demonstrated that cytokines and immune cells play a key role in the testicular development. This reproductive-immune interaction might be very important in the sea bass since several pathogens are able to colonise the gonad and persist in this tissue, altering further reproductive functions and spreading disease. This study aims to investigate the reproductive cycle of 1-year European sea bass males by analysing cell proliferation and apoptosis and the expression profile of some reproductive and immune-related genes in the testis, as well as the serum sex steroid levels. Our data demonstrate that, in 1-year-old European sea bass males, the testis undergoes the spermatogenesis process and that the reproductive and immune parameters analysed varied during the reproductive cycle. In the testis, the highest proliferative rates were recorded at the spermatogenesis stage, while the highest apoptotic rates were recorded at the spawning stage. We have also analysed, for the first time in European sea bass males, the serum levels of 17β-estradiol (E2) and dihydrotestosterone and the gene expression profile of the enzymes implied in their production, determining that at least E2 might be involved in the regulation of the reproductive cycle. Some immune relevant genes, including cytokines, lymphocyte receptors, and anti-viral and anti-bacterial molecules were detected in the testis of naïve European sea bass specimens, and their expression profile was related to the stages of the reproductive cycle, suggesting an important role for the defence of the reproductive tissues.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Miriam Sánchez-Hernández
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alicia García-Alcázar
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain
| | - Alfonsa García-Ayala
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Alberto Cuesta
- Department of Cell Biology and Histology, Faculty of Biology, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100, Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860, Murcia, Spain.
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21
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Unal G, Marquez EC, Feld M, Stavropoulos P, Callard IP. Isolation of estrogen receptor subtypes and vitellogenin genes: Expression in female Chalcalburnus tarichi. Comp Biochem Physiol B Biochem Mol Biol 2014; 172-173:67-73. [DOI: 10.1016/j.cbpb.2014.04.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 03/17/2014] [Accepted: 04/08/2014] [Indexed: 11/17/2022]
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22
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Rettberg JR, Yao J, Brinton RD. Estrogen: a master regulator of bioenergetic systems in the brain and body. Front Neuroendocrinol 2014; 35:8-30. [PMID: 23994581 PMCID: PMC4024050 DOI: 10.1016/j.yfrne.2013.08.001] [Citation(s) in RCA: 305] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/09/2013] [Accepted: 08/10/2013] [Indexed: 01/12/2023]
Abstract
Estrogen is a fundamental regulator of the metabolic system of the female brain and body. Within the brain, estrogen regulates glucose transport, aerobic glycolysis, and mitochondrial function to generate ATP. In the body, estrogen protects against adiposity, insulin resistance, and type II diabetes, and regulates energy intake and expenditure. During menopause, decline in circulating estrogen is coincident with decline in brain bioenergetics and shift towards a metabolically compromised phenotype. Compensatory bioenergetic adaptations, or lack thereof, to estrogen loss could determine risk of late-onset Alzheimer's disease. Estrogen coordinates brain and body metabolism, such that peripheral metabolic state can indicate bioenergetic status of the brain. By generating biomarker profiles that encompass peripheral metabolic changes occurring with menopause, individual risk profiles for decreased brain bioenergetics and cognitive decline can be created. Biomarker profiles could identify women at risk while also serving as indicators of efficacy of hormone therapy or other preventative interventions.
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Affiliation(s)
- Jamaica R Rettberg
- Neuroscience Department, University of Southern California, Los Angeles, CA 90033, United States
| | - Jia Yao
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Roberta Diaz Brinton
- Neuroscience Department, University of Southern California, Los Angeles, CA 90033, United States; Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States; Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States.
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23
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Cotter KA, Yershov A, Novillo A, Callard GV. Multiple structurally distinct ERα mRNA variants in zebrafish are differentially expressed by tissue type, stage of development and estrogen exposure. Gen Comp Endocrinol 2013; 194:217-29. [PMID: 24090614 PMCID: PMC3862120 DOI: 10.1016/j.ygcen.2013.09.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 09/04/2013] [Accepted: 09/18/2013] [Indexed: 10/26/2022]
Abstract
It is well established that estrogen-like environmental chemicals interact with the ligand-binding site of estrogen receptors (ERs) to disrupt transcriptional control of estrogen responsive targets. Here we investigate the possibility that estrogens also impact splicing decisions on estrogen responsive genes, such as that encoding ERα itself. Targeted PCR cloning was applied to identify six ERα mRNA variants in zebrafish. Sequencing revealed alternate use of transcription and translation start sites, multiple exon deletions, intron retention and alternate polyadenylation. As determined by quantitative (q)PCR, N-terminal mRNA variants predicting long (ERαA(L)) and short (ERα(S)) isoforms were differentially expressed by tissue-type, sex, stage of development and estrogen exposure. Whereas ERα(L) mRNA was diffusely distributed in liver, brain, heart, eye, and gonads, ERα(S) mRNA was preferentially expressed in liver (female>male) and ovary. Neither ERα(L) nor ERα(S) transcripts varied significantly during development, but 17β-estradiol selectively increased accumulation of ERα(S) mRNA (∼170-fold by 120 hpf), an effect mimicked by bisphenol-A and diethylstilbestrol. Significantly, a C-truncated variant (ERα(S)-Cx) lacking most of the ligand binding and AF-2 domains was transcribed exclusively from the short isoform promoter and was similar to ERα(S) in its tissue-, stage- and estrogen inducible expression. These results support the idea that promoter choice and alternative splicing of the esr1 gene of zebrafish are part of the autoregulatory mechanism by which estrogen modulates subsequent ERα expression, and further suggest that environmental estrogens could exert some of their toxic effects by altering the relative abundance of structurally and functionally distinct ERα isoforms.
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Affiliation(s)
- Kellie A. Cotter
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Anya Yershov
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Apolonia Novillo
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
| | - Gloria V. Callard
- Boston University Department of Biology, 5 Cummington Mall, Boston, MA 02215, USA
- Corresponding author: (617-353-8980)
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24
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Segner H, Casanova-Nakayama A, Kase R, Tyler CR. Impact of environmental estrogens on Yfish considering the diversity of estrogen signaling. Gen Comp Endocrinol 2013; 191:190-201. [PMID: 23763869 DOI: 10.1016/j.ygcen.2013.05.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2012] [Revised: 05/16/2013] [Accepted: 05/29/2013] [Indexed: 12/31/2022]
Abstract
Research on endocrine disruption in fish has been dominated by studies on estrogen-active compounds which act as mimics of the natural estrogen, 17β-estradiol (E2), and generally exert their biological actions by binding to and activation of estrogen receptors (ERs). Estrogens play central roles in reproductive physiology and regulate (female) sexual differentiation. In line with this, most adverse effects reported for fish exposed to environmental estrogens relate to sexual differentiation and reproduction. E2, however, utilizes a variety of signaling mechanisms, has multifaceted functions and targets, and therefore the toxicological and ecological effects of environmental estrogens in fish will extend beyond those associated with the reproduction. This review first describes the diversity of estrogen receptor signaling in fish, including both genomic and non-genomic mechanisms, and receptor crosstalk. It then considers the range of non-reproductive physiological processes in fish that are known to be responsive to estrogens, including sensory systems, the brain, the immune system, growth, specifically through the growth hormone/insulin-like growth factor system, and osmoregulation. The diversity in estrogen responses between fish species is then addressed, framed within evolutionary and ecological contexts, and we make assessments on their relevance for toxicological sensitivity as well as ecological vulnerability. The diversity of estrogen actions raises questions whether current risk assessment strategies, which focus on reproductive endpoints, and a few model fish species only, are protective of the wider potential health effects of estrogens. Available - although limited - evidence nevertheless suggests that quantitative environmental threshold concentrations for environmental protection derived from reproductive tests with model fish species are protective for non-reproductive effects as well. The diversity of actions of estrogens across divergent physiological systems, however, may lead to and underestimation of impacts on fish populations as their effects are generally considered on one functional process only and this may underrepresent the impact on the different physiological processes collectively.
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Affiliation(s)
- Helmut Segner
- Centre for Fish and Wildlife Health, University of Bern, Bern, Switzerland.
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25
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Mu W, Wen H, Shi D, Yang Y. Molecular cloning and expression analysis of estrogen receptor betas (ERβ1 and ERβ2) during gonad development in the Korean rockfish, Sebastes schlegeli. Gene 2013; 523:39-49. [DOI: 10.1016/j.gene.2013.03.109] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 03/20/2013] [Accepted: 03/25/2013] [Indexed: 10/26/2022]
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26
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Li W, Zhang J, Mu W, Wen H. Cloning, characterization and expression of estrogen receptor beta in the male half-smooth tongue sole, Cynoglossus semilaevis. FISH PHYSIOLOGY AND BIOCHEMISTRY 2013; 39:671-682. [PMID: 23053612 DOI: 10.1007/s10695-012-9729-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Accepted: 09/25/2012] [Indexed: 06/01/2023]
Abstract
A full-length sequence encoding the estrogen receptor beta was isolated from half-smooth tongue sole, Cynoglossus semilaevis (hstsERβ) using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends procedures. The hstsERβ cDNA clone was found to contain 1,791 nucleotides including an open reading frame that encodes 578 amino acids. The deduced hstsERβ protein consisted of six nuclear receptor-characteristic domains. Based on a phylogenetic analysis, the hstsERβ C and E domains are highly conserved compared to other fishes. The potential phosphorylation sites for PKC, CK-2 and PTK are also found in this protein. Highest amino acid identities were found for hstsERβ with common carp (Cyprinus carpio) ERβ (76 %) and Japanese flounder (Paralichthys olivaceus) ERβ (76 %). Tissue expression analysis confirmed that the hstsERβ was widely distributed and predominantly expressed in testis, brain and liver. Seasonal changes in the testis, brain and liver expression profiles of hstsERβ were examined by RT-PCR; the present results suggest that level of hstsERβ in brain increased to the highest then decreases with gonadal growth; whereas in the testis and liver, the hstsERβ mRNA level dropped to lowest then slightly increased.
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Affiliation(s)
- Wenge Li
- Fisheries College, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
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27
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Escobar S, Felip A, Gueguen MM, Zanuy S, Carrillo M, Kah O, Servili A. Expression of kisspeptins in the brain and pituitary of the european sea bass (Dicentrarchus labrax). J Comp Neurol 2013; 521:933-48. [DOI: 10.1002/cne.23211] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 05/04/2012] [Accepted: 08/03/2012] [Indexed: 11/09/2022]
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28
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Nagler JJ, Cavileer TD, Verducci JS, Schultz IR, Hook SE, Hayton WL. Estrogen receptor mRNA expression patterns in the liver and ovary of female rainbow trout over a complete reproductive cycle. Gen Comp Endocrinol 2012; 178:556-61. [PMID: 22732076 PMCID: PMC3428511 DOI: 10.1016/j.ygcen.2012.06.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 04/23/2012] [Accepted: 06/08/2012] [Indexed: 01/08/2023]
Abstract
Estrogens are critical hormones involved in reproduction and need to bind to estrogen receptors in target organs for biological activity. Fishes have two distinct estrogen receptor subtypes, alpha (α) and beta (β), with variable combinations of additional isoforms of each subtype dependent on the history of genome duplication within a taxon. The comparative expression patterns of estrogen receptor isoforms during the female reproductive cycle will provide important insights into the unique function and importance of each. The purpose of this study was to measure the mRNAs for the four estrogen receptor isoforms (erα1, erα2, erβ1, erβ2) in the liver and ovary of adult, female rainbow trout over the course of an annual reproductive cycle. The expression of estrogen receptor mRNA isoforms was measured by quantitative real-time RT-PCR. Several reproductive indices (gonadosomatic index, maximum oocyte diameter, plasma estradiol-17β, plasma vitellogenin, and ovulation) were also quantified for comparison and used in a correlation analysis to examine any inter-relationships. Of the four isoforms, the expression of erα1 was highest in the liver, and had a significant positive correlation with liver erβ1 expression. Liver expression of erα2 mRNA was the lowest, but showed a significant positive correlation with maximum oocyte diameter in the ovary. The pattern of the erβ isoforms in liver was one of initially elevated mRNA expression followed by a gradual decrease as reproductive development proceeded. In the ovary the erβ1 isoform had the highest mRNA expression of all estrogen receptor isoforms, at the beginning of the reproductive cycle, but then decreased afterward. Both ovarian erβ isoforms had a significant positive correlation with one another. In contrast, erα2 mRNA expression showed a high maximum level in the ovary near the end of the cycle along with a significant positive correlation with plasma estradiol-17β levels; the highest gonadosomatic indices, maximum oocyte diameter, and vitellogenin levels occurred then too.
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Affiliation(s)
- James J Nagler
- Department of Biological Sciences, University of Idaho, Moscow, ID 83844, USA.
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29
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Zhang Y, Wang H, Qin F, Liu S, Wu T, Li M, Xu P, Zhang X, Wang X, Hu G, Yuan C, Wang Z. Molecular characterization of estrogen receptor genes in loach Paramisgurnus dabryanus and their expression upon 17α-ethinylestradiol exposure in juveniles. Gen Comp Endocrinol 2012; 178:194-205. [PMID: 22705038 DOI: 10.1016/j.ygcen.2012.06.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 05/30/2012] [Accepted: 06/01/2012] [Indexed: 11/30/2022]
Abstract
The full-length cDNAs for estrogen receptor 1 (esr1), esr2a and esr2b were isolated and characterized from the loach (Paramisgurnus dabryanus, Cobitidae, cypriniformes). P. dabryanus Esr1, Esr2a and Esr2b share high amino acids identities with their counterparts of cyprinid species. Quantitative real-time PCR (qRT-PCR) was used to analyze the tissue distribution of esr mRNAs in one-year-old P. dabryanus. The mRNA expression of esr1 in female liver was extremely higher than that in other tissues. esr2a mRNA expression in female intestine and in male muscle was higher than that in other tissues. esr2b mRNA expression was the highest in both male and female intestine. Two-month-old P. dabryanus were exposed to 17α-ethinylestradiol (EE2) for 3weeks and the changes of esr mRNA expression in brain, gonad and liver were analyzed by qRT-PCR. Results showed that EE2 at 1, 5 and 25 ng/L significantly suppressed testicular esr1 mRNA expression in male. The ovarian esr2a mRNA expression was significantly up-regulated at 1 ng/L EE2. In female brain, esr1 mRNA expression was significantly down-regulated at 5 ng/L EE2. Both in males and females, EE2 exposure increased the hepatic esr1 mRNA expression in a concentration-dependent manner. The present study suggests that different esrs in different tissues have differential responsiveness to EE2 and the hepatic esr1 is a sensitive biomarker to EE2 at environmental concentrations in P. dabryanus juveniles. So, the loach P. dabryanus, a typical demersal fish, is a promising ecological model organism to detect estrogenic chemicals in the sediment of aquatic environment by using molecular biomarkers.
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Affiliation(s)
- Yingying Zhang
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China
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Development of an in vitro system for functional studies of ovarian follicular cells in European sea bass (Dicentrarchus labrax). Cytotechnology 2012; 65:273-86. [PMID: 22760552 DOI: 10.1007/s10616-012-9484-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 06/24/2012] [Indexed: 10/28/2022] Open
Abstract
The layers of follicular cells surrounding the oocyte and the interactions among them and the germ cells are critical for the successful maintenance of the ovarian functions. We have set up the isolation procedure and culture conditions of sea bass ovarian follicular cells. Their behaviour at three different physiological temperatures (25, 18 and 15 °C) was evaluated by verifying their steroidogenic capacity along time together with the expression of follicular specific genes (cyp19a1, fshr, lhr and star). These characteristics revealed this culture as a good in vitro alternative to short term in vivo studies at the level of the ovarian follicle. Moreover, to evaluate the suitability of this system for gene function studies conditions for transient transfection of plasmid DNA were optimized. Finally, the characteristics of the follicular culture were not affected by freezing and thawing cycles what facilitates the performance of experiments independently of the reproductive season. In conclusion, we have developed an in vitro homologous system that enables functional and gene expression studies and resembles the in vivo situation in the ovarian follicle.
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31
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Spachmo B, Arukwe A. Endocrine and developmental effects in Atlantic salmon (Salmo salar) exposed to perfluorooctane sulfonic or perfluorooctane carboxylic acids. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2012; 108:112-124. [PMID: 22265611 DOI: 10.1016/j.aquatox.2011.07.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 07/25/2011] [Accepted: 07/29/2011] [Indexed: 05/31/2023]
Abstract
In this study, we have investigated the effect of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) on endocrine signalling, growth and development in Atlantic salmon (Salmo salar) embryos and larvae. Expression of genes related to the hypothalamic-pituitary-thyroid (HPT) axis, growth-hormone/insulin-like growth factor (GH/IGF) axis and the steroid hormone axis were used as indicators of endocrine disruption. We also studied bone development in larvae, both by observing skeletal structure formation and by investigating expression of genes involved in ossification process. Atlantic salmon embryos, kept in plastic tanks at 5-7°C, were exposed to 100 μg/L PFOA or PFOS from egg stage for a period of 52 days, followed by one-week recovery period. Sampling was performed at day 21, 35, 49 and 56 representing age 549, 597, 679 and 721 dd (dd or day degrees = number of days × temperature in degree Celsius:°C). Note that day 56 or 721 dd is the end of the 1-week recovery period. Larvae were divided into designated head and body regions for the purpose of gene expression analysis, except for genes that regulate ossification that were analyzed in whole larvae. Expression of thyroid receptor α and β (TRα and TRβ), thyroid-stimulating hormone β (TSHβ), T(4) outer-ring deiodinase (T(4)ORD), growth hormone (GH), insulin-like growth factor-I and II (IGF-I and II), insulin-like growth factor I receptor (IGF-IR), and estrogen receptor α and β (ERα and ERβ) were investigated using quantitative PCR. Both PFOS and PFOA exposure produced non-significant alterations in larvae weight (except after the recovery period when a decrease was observed), while larvae length was unaffected. PFOS and PFOA exposure produced body- and head region-specific alterations in expression of all the investigated gene transcripts. Expression of IGF-I and IGF-IR paralleled that of GH, indicating that perturbation of GH expression is a possible end point for disruption of the GH-IGF axis. We did not observe developmental changes related to angiogenesis, ossification and chondrogenesis after exposure to PFOS and PFOA. Transcriptional abnormalities may serve as indicators of chronic exposure, although the concrete mechanisms causing the observed effects remain ambiguous. The implications of these findings for the complete lifecycle, including other developmental and/or reproductive damage, are areas of future study.
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Affiliation(s)
- Bård Spachmo
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
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32
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Fang C, Wu X, Huang Q, Liao Y, Liu L, Qiu L, Shen H, Dong S. PFOS elicits transcriptional responses of the ER, AHR and PPAR pathways in Oryzias melastigma in a stage-specific manner. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2012; 106-107:9-19. [PMID: 22057250 DOI: 10.1016/j.aquatox.2011.10.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 10/06/2011] [Accepted: 10/11/2011] [Indexed: 05/31/2023]
Abstract
Perfluorooctane sulfonate (PFOS) is widely distributed in seawater. However, the effects of PFOS on important receptors involved in the toxicity of POPs have not been fully defined, especially for the embryonic stages of marine fish. In this study, we examined the transcriptional responses and PFOS accumulation in the marine medaka embryos at the early and late developmental stages of 4 and 10 dpf upon PFOS exposure (1, 4, and 16mg/L). PFOS accumulated in the embryos, and the embryonic burdens of PFOS at 10 dpf were markedly higher than those at 4 dpf. Moreover, thirteen genes involved in three important POPs-related receptor pathways, including ER, AHR and PPAR, were cloned and investigated. The mRNA expression levels of ERα and ERγ were not significantly altered, but the estrogenic marker genes were downregulated upon PFOS exposure at 4 dpf. Conversely, ERs and related marker genes all were significantly upregulated at 10 dpf. The expressions of ARNT and cyp1a were both upregulated at 4 dpf, while no obvious changes were detected at 10 dpf. The expressions of cyp19a and cyp19b were regulated by PFOS in a stage-specific manner. PFOS produced different effects on three isoforms of PPAR. PPARα and PPARβ were first inhibited at 4 dpf and were induced at 10 dpf. PFOS did not elicit a change in PPARγ expression at either stage. In conclusion, this study showed that PFOS has an estrogenic activity and endocrine-disruptive properties. Meanwhile, PFOS could elicit transcriptional responses on POPs-related pathways in a stage-specific manner.
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Affiliation(s)
- Chao Fang
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China
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33
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Shi D, Wen HS, He F, Li JF, Yang YP, Chen CF, Zhang JR, Chen XY, Jin GX, Shi B, Qi BX, Li N. The physiology functions of estrogen receptor α (ERα) in reproduction cycle of ovoviviparous black rockfish, Sebastes schlegeli Hilgendorf. Steroids 2011; 76:1597-608. [PMID: 22005200 DOI: 10.1016/j.steroids.2011.09.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 09/21/2011] [Accepted: 09/30/2011] [Indexed: 02/07/2023]
Abstract
This paper revealed the expression pattern of ERα in the ovoviviparous teleost, Sebastes schlegeli. In this paper, we isolated the cDNA encoding for estrogen receptor alpha of black rockfish (S. schlegeli) from its ovary, named as black rockfish ERα (brfERα). The cDNA sequence of brfERα consists of 2972bp with an open reading frame encoding a 624 amino acid putative protein which exhibits high identities with other teleosts'. The tissue distribution of brfERα mRNA was examined using RT-PCR. BrfERα showed generally expressions in most tissues of female black rockfish, besides, the higher degree of expressions were seen in ovary, liver, duodenum and fat, whereas it had a more restricted distribution in male fish. In ovary, the expression level of brfERα was as similar as the serum levels of E2 and P in female. However, it was a different situation in male, where the serum concentration of E2 showed higher levels after spermiation and Serum concentration of P did not show any significant changes during a year. Based on the present study, it is supposed that brfERα plays an important role in ovary and other target organs during the reproductive cycle, Further studies will focus on the transcriptional regulation and localization of brfERα in gonad in order to get a better understand of the physiological function of brfERα in ovoviviparous teleost. This study indicates that the black rockfish may be a good candidate for understanding the mechanism of estrogen in ovoviviparous fish.
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Affiliation(s)
- Dan Shi
- Fisheries College, Ocean University of China, Qingdao 266003, China
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34
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Olufsen M, Arukwe A. Developmental effects related to angiogenesis and osteogenic differentiation in Salmon larvae continuously exposed to dioxin-like 3,3',4,4'-tetrachlorobiphenyl (congener 77). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2011; 105:669-680. [PMID: 21979385 DOI: 10.1016/j.aquatox.2011.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 08/31/2011] [Accepted: 09/11/2011] [Indexed: 05/28/2023]
Abstract
We have studied the effects of dioxin-like 3,3',4,4'-tetrachlorobiphenyl (PCB-77) on developmental effects related to angiogenesis and osteogenesis during early life-stages of salmon. Larvae were kept at 6°C and continuously exposed to waterborne PCB-77 (1 or 10 ng/L) initiated at the egg stage or 416-day degrees (dd) and throughout yolk-sac stage (716 dd) and for a total duration of 50 days (or 300 dd). Gene transcription analysis was performed on whole larvae total RNA at 548, 632, 674 and 716 dd using real-time PCR. Bone morphogenetic protein (bmp2 and bmp4), transforming growth factor β (TGF-β), estrogen receptors (ERα and ERβ), runx2, sox9 and collagen type 2 alpha 1 (col2a1) and vascular endothelial growth factor (VEGF) genes were studied. Effect on VEGF gene transcription was related to observation of heart rate, arrhythmia and anemia, demonstrating effects on vascular system development. Alizarine-red staining and quantification of ossified bone structures showed that PCB-77 produced concentration-dependent increases in the rate of osteogenic tissue formation. PCB-77 produced increases in col2a1 and runx2 transcription with subsequent induction of chondrogenesis and osteogenesis, respectively. The transcription of TGF-β gene was associated with ERβ transcription. Transcripts of AhR gene battery were differentially modulated by PCB-77 and these effects were dependent on concentration and larval age. Evidence of vascular system disruption by PCB-77 was observed as cardiac edema, anemia and arrhythmia in exposed individuals and as decreased level of VEGF gene transcription at early age. In general, our data indicate that PCB-77 produced developmental effects related to angiogenesis and osteogenic differentiation and disruption of vascular system development.
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Affiliation(s)
- Marianne Olufsen
- Department of Biology, Norwegian University of Science and Technology (NTNU), Høgskoleringen 5, N7491 Trondheim, Norway
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Katsu Y, Lange A, Miyagawa S, Urushitani H, Tatarazako N, Kawashima Y, Tyler CR, Iguchi T. Cloning, expression and functional characterization of carp,Cyprinus carpio, estrogen receptors and their differential activations by estrogens. J Appl Toxicol 2011; 33:41-9. [DOI: 10.1002/jat.1707] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 05/07/2011] [Accepted: 05/07/2011] [Indexed: 12/23/2022]
Affiliation(s)
| | - Anke Lange
- School of Biosciences, College of Life and Environmental Sciences; University of Exeter; Exeter; EX4 4PS; UK
| | | | | | - Norishisa Tatarazako
- National Institute for Environmental Studies; 16-2 Onogawa; Tsukuba; Ibaraki; 305-8506; Japan
| | - Yukio Kawashima
- Japan NUS Co. Ltd, 7-5-25 Nishi-Shinjyuku; Shinjyuku-ku; Tokyo; 160-0023; Japan
| | - Charles R. Tyler
- School of Biosciences, College of Life and Environmental Sciences; University of Exeter; Exeter; EX4 4PS; UK
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Chen H, Zhang Y, Li S, Lin M, Shi Y, Sang Q, Liu M, Zhang H, Lu D, Meng Z, Liu X, Lin H. Molecular cloning, characterization and expression profiles of three estrogen receptors in protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides). Gen Comp Endocrinol 2011; 172:371-81. [PMID: 21473869 DOI: 10.1016/j.ygcen.2011.03.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 03/18/2011] [Accepted: 03/27/2011] [Indexed: 11/29/2022]
Abstract
Estrogen plays key roles in vertebrate reproductive system via estrogen receptors (ERs) as mediating pathways. In the present study, three full-length ERs cDNA sequences were isolated from a protogynous teleost, the orange-spotted grouper (Epinephelus coioides), and were 2235bp for gERα, 1967bp for gERβ1 and 2158bp for gERβ2, respectively. Phylogenetic and amino acid alignment analyses showed that each gER was clustered in the corresponding taxonomic groups of the perciformes and exhibited high evolutional conservation in functional domains. RT-PCR revealed that gERs expressed at different levels in all the obtained tissues. gERα highly expressed in mature ovaries, gERβ1 mainly expressed in immature ovaries and gERβ2 varied greatly during ovarian development. During female to male sex reversal induced by 17α-methyltestosterone (MT) implantation, gERα decreased gradually, gERβ1 increased gradually, and gERβ2 decreased firstly and recovered subsequently in male stage. The present study speculated the potential roles of gERs during female maturation and female to male sex reversal induced by MT in the protogynous grouper E. coioides.
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Affiliation(s)
- Huapu Chen
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals, Sun Yat-Sen University, Guangzhou, Guangdong, China
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Lynn SG, Wallat GK, Malison JA, Shepherd BS. Developmental expression and estrogen responses of endocrine genes in juvenile yellow perch (Perca flavescens). Gen Comp Endocrinol 2011; 171:151-9. [PMID: 21216244 DOI: 10.1016/j.ygcen.2011.01.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 11/24/2010] [Accepted: 01/03/2011] [Indexed: 12/13/2022]
Abstract
The present study examines the expression of growth-regulating genes (gh, prl, smtl and igf1b), the estrogen receptors (esr1 and esr2a) and aromatase (cyp19a1a) in developing yellow perch. To gain an initial understanding into the endocrine control of growth preceding and involved with sexual size dimorphism (SSD), where females have been reported to grow faster and larger than males, young of the year fish were sampled for length, weight and tissues at several time points (102-421 days post-hatch (dph)). Positive growth was seen in both sexes over the sampling interval, but SSD was not manifested. Using real-time quantitative PCR, we found that pituitary growth hormone (gh) and liver insulin-like growth factor-1b (igf1b) mRNA levels were significantly affected by dph and levels were found to be correlated with growth in both sexes. Liver cyp19a1a, esr1 and esr2a mRNA levels were significantly influenced by dph, whereas there was a significant dph*sex interaction on liver esr2a mRNA levels with males having higher levels than females at 379 and 421 dph. Ovarian cyp19a1a decreased with dph, but there were no changes in esr1 or esr2a mRNA levels. Dietary treatment of juvenile (∼300 dph) females with 20 mg/kg diet 17β-estradiol resulted in significantly higher liver esr1 mRNA levels and a sustained hepatosomatic index (I(H)). Across all data sets liver esr2a mRNA levels showed the most significant positive correlation with liver igf1b mRNA levels. These findings show that growth is accompanied by increases in pituitary gh, liver igf1b and liver esr1 and esr2a mRNAs in juvenile yellow perch.
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Affiliation(s)
- Scott G Lynn
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA.
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Kim JG, Kim HR, Park YJ, Chung KH, Oh SM. Molecular Cloning and Characterization of the Estrogen Receptor from the Striped Bitterling (Acheilognathus yamatsutae). ENVIRONMENTAL HEALTH AND TOXICOLOGY 2011; 26:e2011005. [PMID: 22125766 PMCID: PMC3214976 DOI: 10.5620/eht.2011.26.e2011005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 02/25/2011] [Indexed: 05/31/2023]
Abstract
OBJECTIVES In order to identify the possibility of striped bitterling (SB) (Acheilognathus yamatsutae) being used as a test species for estrogenic endocrine disrupting chemicals (EEDCs), we carried out the cloning and sequence characterization of the estrogen receptor (ER). METHODS The ER from a striped bitterling was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR), 5'- and 3'-rapid amplification of cDNA ends (5'-RACE and 3'-RACE) and T-vector cloning. The expression of ER mRNA was also analyzed in six tissues (brain, liver, kidney, gill, gonad, and intestines) by real-time PCR. RESULTS We obtained an ER from the striped bitterling. The SB ER cDNA was 2189 base pairs (bp) in length and contained a 1707 bp open reading frame that encoded 568 amino acid residues. The SB ER amino acid sequence clustered in a monophyletic group with the ERα of other fish, and was more closely related to zebrafish ERα (88% identity) than to the ERα of other fish. The SB ER cDNA was divided into A/B, C, D, E and F domains. The SB ER has conserved important sequences for ER functions, such as the DNA binding domain (D domain), which are consistent with those of other teleosts. CONCLUSIONS The ER of the striped bitterling could provide basic information in toxicological studies of EEDCs in the striped bitterling.
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Affiliation(s)
- Jong Geuk Kim
- College of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Ha Ryong Kim
- College of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | - Yong Joo Park
- College of Pharmacy, Sungkyunkwan University, Suwon, Korea
| | | | - Seung Min Oh
- Hoseo Toxicological Research Center, Hoseo University, Asan, Korea
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Davis LK, Katsu Y, Iguchi T, Lerner DT, Hirano T, Grau EG. Transcriptional activity and biological effects of mammalian estrogen receptor ligands on three hepatic estrogen receptors in Mozambique tilapia. J Steroid Biochem Mol Biol 2010; 122:272-8. [PMID: 20553864 DOI: 10.1016/j.jsbmb.2010.05.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Revised: 05/19/2010] [Accepted: 05/20/2010] [Indexed: 12/21/2022]
Abstract
Like other fish species, Mozambique tilapia has three forms of estrogen receptor, ERα, ERβ1, and ERβ2. A primary function of 17β-estradiol (E(2)) in oviparous species is the hepatic induction of the yolk precursor protein, vitellogenin (Vg). To characterize the roles of ERs in Vg production, transactivation assays and an in vivo study were carried out utilizing agonists for mammalian ERα and ERβ, and an antagonist for mammalian ERα, propyl-pyrazole-triol (PPT), diarylpropionitrile (DPN), and methyl-piperidino-pyrazole (MPP), respectively. ERα was more sensitive and responsive to PPT than ERβ1 or ERβ2 in transactivation assays. All ER isoforms indicated equivalent responsiveness to DPN compared with E(2), although sensitivity to DPN was lower. MPP exhibited antagonistic action on transactivation of all ER isoforms and reduced the E(2) effect on Vg and ERα 48h post-injection. DPN increased ERα and Vg expression and plasma Vg post-injection, whereas PPT was without effect; DPN seems to stimulate Vg production through activation of ERα. The ligand binding domain of all tilapia ER forms shares only 60-65% amino acid identity with human ERα and ERβ. This, together with our results, clearly indicates that agonistic or antagonistic characteristics of PPT, DPN and MPP cannot be extrapolated from mammalian to piscine ERs.
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Affiliation(s)
- L K Davis
- Hawaii Institute of Marine Biology, University of Hawaii, PO Box 1346, Kaneohe, HI 96744, USA
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Kim NN, Jin DH, Lee J, Kil GS, Choi CY. Upregulation of estrogen receptor subtypes and vitellogenin mRNA in cinnamon clownfish Amphiprion melanopus during the sex change process: profiles on effects of 17beta-estradiol. Comp Biochem Physiol B Biochem Mol Biol 2010; 157:198-204. [PMID: 20601066 DOI: 10.1016/j.cbpb.2010.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 06/17/2010] [Accepted: 06/17/2010] [Indexed: 01/30/2023]
Abstract
In the present study, we investigated the expression pattern of estrogen receptors (esr) and vitellogenin (vtg) mRNA in the gonads and liver during sex change in cinnamon clownfish by using quantitative polymerase chain reaction. We divided gonadal development during the sex change from male to female into 3 stages (mature male, male at 90days after removing female, and mature female) and investigated esr and vtg mRNA expressions during the sex change. With female, the esr and vtg mRNA expressions increased. In western blot analysis, Esr1 protein was detected only in the ovaries of female cinnamon clownfish. Also, to understand the effect of 17beta-estradiol (E(2)), we investigated the esr and vtg mRNA expression patterns in the gonads and liver, and the changes in plasma E(2) level after E(2) injection. E(2) treatment increased both mRNA expression levels of esr and vtg and plasma E(2) levels. The present study describes the molecular characterization of esr subtypes and the interactions between esr and vtg after E(2) treatment in cinnamon clownfish.
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Affiliation(s)
- Na Na Kim
- Division of Marine Environment & BioScience, Korea Maritime University, Busan 606-791, Republic of Korea
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Woods M, Kumar A, Barton M. Nucleotide sequence, tissue expression patterns and phylogenetic analysis of estrogen receptor one mRNA in the Murray rainbowfish (Melanotaenia fluviatilis) (Atheriniformes, Actinopterygii). Gen Comp Endocrinol 2010; 166:529-36. [PMID: 20171224 DOI: 10.1016/j.ygcen.2010.02.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 02/12/2010] [Accepted: 02/15/2010] [Indexed: 11/15/2022]
Abstract
Estrogens are steroidal hormones that control many physiological processes in both female and male vertebrates. Like other vertebrates, fish have two distinct estrogen receptors (Esr) subtypes, Esr1 and Esr2a that have been isolated in a number of species, as well as a third subtype, Esr2b. The mRNA encoding the Esr1 was isolated from the female liver of an Australian freshwater fish, the Murray rainbowfish, Melanotaenia fluviatilis. The rainbowfish esr1 cDNA was 2569 bp in length and with an open reading frame to encode a protein of 611 amino acids. Phylogenetic analysis and multiple amino acid sequence alignment indicated close relationship and high similarity with killifish (Fundulus heteroclitus) and gilthead sea bream (Sparus aurata). Expression of rainbowfish esr1 mRNA was abundant in the liver, gonads and intestine of adult female and male rainbowfish. This is the first isolation of the full-length nucleotide sequence of an estrogen receptor from rainbowfish. This sequence provides a valuable molecular tool that can be used in future studies investigating estrogen mechanisms, actions and tissue-specific expression in juvenile and adult rainbowfish.
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Affiliation(s)
- Marianne Woods
- Centre for Environmental Contaminants Research, CSIRO Land and Water, PMB 2, Glen Osmond 5064, Australia.
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Blázquez M, Somoza GM. Fish with thermolabile sex determination (TSD) as models to study brain sex differentiation. Gen Comp Endocrinol 2010; 166:470-7. [PMID: 19854192 DOI: 10.1016/j.ygcen.2009.10.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 10/20/2009] [Indexed: 11/16/2022]
Abstract
As fish are ectothermic animals, water temperature can affect their basic biological processes such as larval development, growth and reproduction. Similar to reptiles, the incubation temperature during early phases of development is capable to modify sex ratios in a large number of fish species. This phenomenon, known as thermolabile sex determination (TSD) was first reported in Menidia menidia, a species belonging to the family Atherinopsidae. Since then, an increasing number of fish have also been found to exhibit TSD. Traditionally, likewise in reptiles, several TSD patterns have been described in fish, however it has been recently postulated that only one, females at low temperatures and males at high temperatures, may represent the "real" or "true" TSD. Many studies regarding the influence of temperature on the final sex ratios have been focused on the expression and activity of gonadal aromatase, the enzyme involved in the conversion of androgens into estrogens and encoded by the cyp19a1a gene. In this regard, teleost fish, may be due to a whole genome duplication event, produce another aromatase enzyme, commonly named brain aromatase, encoded by the cyp19a1b gene. Contrary to what has been described in other vertebrates, fish exhibit very high levels of aromatase activity in the brain and therefore they synthesize high amounts of neuroestrogens. However, its biological significance is still not understood. In addition, the mechanism whereby temperature can induce the development of a testis or an ovary still remains elusive. In this context the present review is aimed to discuss several theories about the possible role of brain aromatase using fish as models. The relevance of brain aromatase and therefore of neuroestrogens as the possible cue for gonadal differentiation is raised. In addition, the possible role of brain aromatase as the way to keep the high levels of neurogenesis in fish is also considered. Several key examples of how teleosts and aromatase regulation can offer more insight into basic mechanisms of TSD are also reviewed.
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Affiliation(s)
- Mercedes Blázquez
- Instituto de Ciencias del Mar, Consejo Superior de Investigaciones Científicas, Paseo Marítimo 37-49, 08003 Barcelona, Spain.
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Blázquez M, Navarro-Martín L, Piferrer F. Expression profiles of sex differentiation-related genes during ontogenesis in the European sea bass acclimated to two different temperatures. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2009; 312:686-700. [PMID: 19338052 DOI: 10.1002/jez.b.21286] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The European sea bass is a teleost fish that lacks sex chromosomes and for which temperature influences sex ratios. However, correlation between temperature, developmental stage at a given age and sex-specific gene expression is hampered by the lack of sex markers. To study this correlation, fish were exposed to feminizing (15 degrees C) or masculinizing temperature (21 degrees C) from 0-120 days post fertilization, throughout the thermosensitive period (TSP). Aromatase (cyp19a1a), 11beta-hydroxylase (cyp11b), androgen receptor (arb) and estrogen receptors (era, erb1 and erb2) were assessed by qPCR prior and during sex differentiation. Canonical discriminant analysis (CDA), with length--as proxy for developmental stage--and cyp19a1a expression as predictors, was validated and used to reliably assign gonadal sex to fish sampled within and outside the TSP. Differences in cyp19a1a and cyp11b expression could be detected 1-month before the first signs of histological sex differentiation. Cyp19a1a and cyp11b were significantly higher in future females and males, respectively, and revealed as robust molecular markers to predict future ovarian and testicular differentiation. In contrast, no association between phenotypic sex and arb, era, erb1 and erb2 expression was found, suggesting that these genes do not contribute to the differentiation of a particular sex. The CDA-based approach implemented here could be used to sex undifferentiated animals in species where genetic sex cannot be known owing to the lack of simple sex determining systems, as it is the case of many fish and reptiles with or without temperature-dependent sex determination, and provide a useful tool to relate gene expression and phenotypic sex.
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Affiliation(s)
- Mercedes Blázquez
- Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain
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Martyniuk CJ, Kroll KJ, Porak WF, Steward C, Grier HJ, Denslow ND. Seasonal relationship between gonadotropin, growth hormone, and estrogen receptor mRNA expression in the pituitary gland of largemouth bass. Gen Comp Endocrinol 2009; 163:306-17. [PMID: 19416730 PMCID: PMC4188826 DOI: 10.1016/j.ygcen.2009.04.028] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2008] [Revised: 04/05/2009] [Accepted: 04/27/2009] [Indexed: 11/22/2022]
Abstract
The objectives of this study were to investigate the seasonal changes in pituitary gonadotropins, growth hormone (GH), and estrogen receptor (ER) isoform mRNA in wild female and male largemouth bass (LMB) (Micropterus salmoides) from an unpolluted habitat to better understand reproductive physiology in this ecologically important species. Female pituitary luteinizing hormone (LH) beta subunit and follicle stimulating hormone (FSH) beta subunit mRNA showed significant seasonal variation with levels peaking from January to April and were lowest from May to August. Male LMB showed more variation in gonadotropin subunit expression from month to month. Females had approximately 2-3 times higher gonadotropin mRNA levels in the pituitary when compared to males. All three gonadotropin mRNAs in females were positively correlated to gonadosomatic index (GSI), but only LHbeta mRNA was correlated to GSI in males. Gonadotropin mRNA expression also increased with increasing oocyte and sperm maturation. Gonadotropin beta subunit mRNA expression was positively correlated to GH mRNA in both sexes. The expression of all three ER isoforms was significantly correlated to each other in both sexes. The concurrent increase in all three ER mRNA isoforms with increasing gonadotropin mRNA in females and males suggests a prominent role for E2 feedback on pituitary gonadotropin synthesis in both sexes and that each of the three ER isoforms are likely to play a role in the pituitary during teleost reproduction.
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Affiliation(s)
- Christopher J Martyniuk
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, 32611 USA
| | - Kevin J. Kroll
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, 32611 USA
| | - Wesley F. Porak
- Florida Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Eustis, FL 32726 USA
| | - Cheree Steward
- Florida Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Eustis, FL 32726 USA
| | - Harry J. Grier
- Florida Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL 33701, USA
| | - Nancy D. Denslow
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, 32611 USA
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Single nucleotide polymorphisms within the estrogen receptor beta gene are linked with reproductive indices in Japanese flounder, Paralichthys olivaceus. Comp Biochem Physiol B Biochem Mol Biol 2009; 154:62-7. [PMID: 19427917 DOI: 10.1016/j.cbpb.2009.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 05/02/2009] [Accepted: 05/02/2009] [Indexed: 11/23/2022]
Abstract
The objectives of this study were to characterize polymorphisms within the coding region of estrogen receptor beta (ERbeta) gene in a population of 57 female Japanese flounder (Paralichthys olivaceus) and to analyze the association of ERbeta polymorphisms with reproductive indices by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). Two single nucleotide polymorphisms (SNPs), SNP1 (c.577delC) and SNP2 [c.A891T (p.Gln114Leu)], were identified in the ERbeta gene. A one-way ANOVA revealed that SNP1 was significantly associated with the gonadosomatic index (GSI) in female Japanese flounder (P < 0.05). And SNP2 was significantly associated with the serum 17beta-estradiol (E2) level and GSI (P < 0.05). Individuals with genotype AB of SNP2 had significantly higher serum E2 level and GSI than those of genotype AA (P < 0.05). Moreover, the hepatosomatic index (HSI), a marker for genetic effects, was significantly higher for diplotype D2 compared with the other three diplotypes (P < 0.05). These results obtained in this study suggested that SNP2 could influence reproductive endocrinology of female Japanese flounder and be useful as a potential candidate genetic marker for the selection of reproductive indices in female Japanese flounder.
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Woods M, Kumar A, Barton M, Woods A, Kookana R. Localisation of estrogen responsive genes in the liver and testis of Murray rainbowfish Melanotaenia fluviatilis exposed to 17beta-estradiol. Mol Cell Endocrinol 2009; 303:57-66. [PMID: 19428992 DOI: 10.1016/j.mce.2008.12.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 11/19/2008] [Accepted: 12/31/2008] [Indexed: 10/21/2022]
Abstract
The localisation of estrogen receptors (ERalpha and ERbeta) and vitellogenin (VTG) transcripts were examined in the liver and testis in male rainbowfish exposed to 17beta-estradiol (E2; 0, 50 and 500 ng/L) via the water for up to 7 days. The ER transcripts were localised within the perinuclear region of the hepatocytes and were up-regulated with E2 exposure. A parallel induction of liver VTG transcripts and protein was observed within 24h, followed by a time-dependent increase in VTG protein. In the testis, both ERs were up-regulated in the germ and epithelial cells, while VTG protein was detected in the cellular space surrounding the spermatids and in association with the connective tissue of the sperm tubules. These results indicate that the ERs are positively auto-regulated in the liver and testis of male rainbowfish. The cellular localisation of VTG within the testis may suggest implication in the mediation of adverse effects of endocrine disrupting chemicals such as testicular growth inhibition, testis-ova and sex reversal.
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Affiliation(s)
- Marianne Woods
- Centre for Environmental Contaminants Research, CSIRO Land and Water, Glen Osmond, Australia.
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47
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Davis LK, Visitacion N, Riley LG, Hiramatsu N, Sullivan CV, Hirano T, Grau EG. Effects of o,p'-DDE, heptachlor, and 17beta-estradiol on vitellogenin gene expression and the growth hormone/insulin-like growth factor-I axis in the tilapia, Oreochromis mossambicus. Comp Biochem Physiol C Toxicol Pharmacol 2009; 149:507-14. [PMID: 19101654 DOI: 10.1016/j.cbpc.2008.11.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 11/20/2008] [Accepted: 11/21/2008] [Indexed: 02/02/2023]
Abstract
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).
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Affiliation(s)
- Lori K Davis
- Hawaii Institute of Marine Biology, Department of Zoology, University of Hawaii, Kaneohe, HI 96744, USA
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48
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Lynn SG, Powell KA, Westneat DF, Shepherd BS. Seasonal and sex-specific mRNA levels of key endocrine genes in adult yellow perch (Perca flavescens) from Lake Erie. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2009; 11:210-222. [PMID: 18810549 DOI: 10.1007/s10126-008-9136-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Accepted: 07/27/2008] [Indexed: 05/26/2023]
Abstract
To better understand the endocrine mechanisms that underlie sexually dimorphic growth (females grow faster) in yellow perch (Perca flavescens), real-time quantitative polymerase chain reaction (qPCR) was used to measure pituitary, liver, and ovary mRNA levels of genes related to growth and reproduction-sex in this species. Adult perch were collected from Lake Erie and body mass, age, gonadosomatic index (I (G)), hepatosomatic index (I (H)), and gene expression for growth hormone (GH), prolactin, somatolactin, insulin-like growth factor Ib (IGF-Ib), estrogen receptor alpha (esr1), estrogen receptor betaa (esr2a), and aromatase (cyp19a1a) were measured. Females had higher body mass, I (H), and liver esr1 mRNA level than males, while males had higher liver IGF-Ib, liver esr2a, and liver cyp19a1a mRNA levels. In both sexes, season had a significant effect on GH and liver IGF-Ib mRNAs with higher levels occurring in spring, which also corresponded with higher liver cyp19a1a mRNA levels. For females, I (G), liver esr1, and ovary cyp19a1a mRNA levels were higher in autumn than the spring, and ovary cyp19a1a mRNA levels showed a significant negative correlation with pituitary GH and liver IGF-Ib mRNA levels. The most significant (p </= 0.001) relationships across the parameters measured were positive correlations between liver IGF-Ib and esr2a mRNA levels and liver IGF-Ib and cyp19a1a mRNA levels. This study shows significant effects of season and sex on adult yellow perch endocrine physiology.
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Affiliation(s)
- S G Lynn
- Department of Biology, University of Kentucky, Lexington, KY 40506-0225, USA.
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Raingeard D, Cancio I, Cajaraville MP. Cloning and expression pattern of peroxisome proliferator-activated receptors, estrogen receptor alpha and retinoid X receptor alpha in the thicklip grey mullet Chelon labrosus. Comp Biochem Physiol C Toxicol Pharmacol 2009; 149:26-35. [PMID: 18619562 DOI: 10.1016/j.cbpc.2008.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 06/17/2008] [Accepted: 06/17/2008] [Indexed: 02/07/2023]
Abstract
Aquatic organisms are exposed to diverse xenobiotics that cause peroxisome proliferation and/or endocrine disruption, both modulated in vertebrates by transcription factors of the nuclear receptor (NR) superfamily. Peroxisome proliferators are agonists of peroxisome proliferator-activated receptors (PPARs) that heterodimerize with the retinoid X receptor (RXR). Many xenoestrogens activate the estrogen receptor (ER). Here, 1090 bp of PPARalpha, 1255 bp of PPARgamma, 278 bp of RXRalpha, and 578 bp of ERalpha of thicklip grey mullet Chelon labrosus were cloned. Sequences were highly conserved, although relevant changes with respect to mammalian homologs were identified in PPARgamma and ERalpha. Semi-quantitative RT-PCR was used to determine if these NRs were expressed in different tissues of male, female and undifferentiated mullets captured in January and June. Expression of PPARs was highest in liver and lowest in muscle. RXRalpha expression was homogeneous excepting a low expression in male and female gill in January and brain and heart of undifferentiated fish in January and June. ERalpha expression predominated in liver and female gonad in June. The expression level of PPARs and ERalpha was significantly higher in liver in January than in gills in January or June. The present results show tissue-dependent modulation of expression of NRs in mullets.
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Affiliation(s)
- Damien Raingeard
- Laboratory of Cell Biology and Histology, Department of Zoology and Animal Cell Biology, University of the Basque Country, Bilbao, Basque Country, Spain
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50
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Navarro-Martín L, Blázquez M, Piferrer F. Masculinization of the European sea bass (Dicentrarchus labrax) by treatment with an androgen or aromatase inhibitor involves different gene expression and has distinct lasting effects on maturation. Gen Comp Endocrinol 2009; 160:3-11. [PMID: 18983844 DOI: 10.1016/j.ygcen.2008.10.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 09/23/2008] [Accepted: 10/06/2008] [Indexed: 10/21/2022]
Abstract
The objective of this study was to contribute to our understanding of the role of sex steroids in fish sex differentiation and male maturation. Sexually undifferentiated sea bass were administered 17alpha-methyldihydrotestosterone (MDHT), estradiol-17beta (E(2)), fadrozole (Fz), cyproterone acetate (CPA) or tamoxifen (Tx). MDHT produced 100% males whereas E(2) and Tx resulted in 100% females. Fz produced 95% males while CPA did not alter sex ratios. E(2) treatment did not affect gonadal aromatase (cyp19a) expression levels, supporting the possibility that the feminizing effect of exogenous E(2) are not directly related to cyp19a regulation. Both MDHT and Fz decreased cyp19a expression. Moreover, androgen receptor (ar) expression levels increased during development in all but the MDHT group, suggesting that early exposure to an androgen down-regulates subsequent ar expression in males and that Fz does not interact with the androgen receptor. Together, these observations indicate that although MDHT and Fz result in a similar phenotype, the molecular pathways involved are likely different, and show that Fz masculinization is the consequence of inhibited ovarian differentiation rather than of a direct androgenic effect. Further, since CPA did not alter sex ratios when administered during the period of highest androgen sensitivity, we suggest that androgens are not required for initial testicular differentiation in the sea bass. MDHT and Fz did not alter the number of precocious males but reduced and increased, respectively, their gonadosomatic index (GSI). In addition, Fz had lasting effects on the GSI of precocious and non-precocious males, probably due to alterations of estrogen function in the testis.
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Affiliation(s)
- Laia Navarro-Martín
- Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas, Passeig Marítim, Barcelona, Spain
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