RT Journal Article
SR Electronic
T1 G protein-coupled estrogen receptor is not required for sex determination or ovary function in zebrafish
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 373092
DO 10.1101/373092
A1 Camerron M. Crowder
A1 Shannon N. Romano
A1 Daniel A. Gorelick
YR 2018
UL http://biorxiv.org/content/early/2018/07/20/373092.abstract
AB Estrogens regulate vertebrate development and function through binding to nuclear estrogen receptors alpha and beta (ERα, ERβ) and the G protein-coupled estrogen receptor (GPER). Studies in mutant animal models demonstrated that ERα and ERβ are required for normal ovary development and function. However, the degree to which GPER signaling contributes to ovary development and function is less well understood. Previous studies using cultured fish oocytes found that estradiol inhibits oocyte maturation in a GPER-dependent manner, but whether GPER regulates oocyte maturation in vivo is not known. To test the hypothesis that GPER regulates oocyte maturation in vivo, we assayed ovary development and function in gper mutant zebrafish. We found that homozygous mutant gper embryos developed into male and female adults with normal sex ratios and fertility. Adult mutant fish exhibited normal secondary sex characteristics and fertility. Additionally, mutant ovaries were histologically normal. We observed no differences in the number of immature versus mature oocytes in mutant versus wild-type ovaries from both young and aged adults. Furthermore, expression of genes associated with sex determination and ovary function were normal in gper mutant ovaries compared to wild type. Our findings suggest that GPER is not required for sex determination, ovary development or fertility in zebrafish.