RRC ID 50460
Author Tohyama S, Ogino Y, Lange A, Myosho T, Kobayashi T, Hirano Y, Yamada G, Sato T, Tatarazako N, Tyler CR, Iguchi T, Miyagawa S.
Title Establishment of estrogen receptor 1 (ESR1)-knockout medaka: ESR1 is dispensable for sexual development and reproduction in medaka, Oryzias latipes.
Journal Dev. Growth Differ.
Abstract Estrogens play fundamental roles in regulating reproductive activities and they act through estrogen receptor (ESR) in all vertebrates. Most vertebrates have two ESR subtypes (ESR1 and ESR2), whereas teleost fish have at least three (Esr1, Esr2a and Esr2b). Intricate functionalization has been suggested among the Esr subtypes, but to date, distinct roles of Esr have been characterized in only a limited number of species. Study of loss-of-function in animal models is a powerful tool for application to understanding vertebrate reproductive biology. In the current study, we established esr1 knockout (KO) medaka using a TALEN approach and examined the effects of Esr1 ablation. Unexpectedly, esr1 KO medaka did not show any significant defects in their gonadal development or in their sexual characteristics. Neither male or female esr1 KO medaka exhibited any significant changes in sexual differentiation or reproductive activity compared with wild type controls. Interestingly, however, estrogen-induced vitellogenin gene expression, an estrogen-responsive biomarker in fish, was limited in the liver of esr1 KO males. Our findings, in contrast to mammals, indicate that Esr1 is dispensable for normal development and reproduction in medaka. We thus provide an evidence for estrogen receptor functionalization between mammals and fish. Our findings will also benefit interpretation of studies into the toxicological effects of estrogenic chemicals in fish.
Volume 59(6)
Pages 552-561
Published 2017-8
DOI 10.1111/dgd.12386
PMID 28782810
MeSH Animals Animals, Genetically Modified Environmental Biomarkers / genetics Environmental Biomarkers / physiology Estrogen Receptor alpha / genetics Estrogen Receptor alpha / metabolism* Female Fish Proteins / genetics Fish Proteins / metabolism* Male Oryzias / genetics Oryzias / physiology* Reproduction / genetics Reproduction / physiology* Sexual Development / genetics Sexual Development / physiology*
IF 1.496
Resource
Medaka esr1(del25) (MT1198) OK-Cab (MT830)