<i>Srd5a1</i> is differentially regulated and methylated during pre-pubertal development in the ovary and hypothalamus

Abstract 5α-reductase-1 catalyzes production of various steroids, including neurosteroids. We reported previously that expression its encoding gene, Srd5a1, drops in murine ovaries and hypothalamic pre-optic area (POA) after early-life immune stress, seemingly contributing to delayed puberty ovarian follicle depletion, while their the first intron was more methylated at two CpGs. Here we hypothesized this CpG-containing locus comprises a methylation-sensitive transcriptional enhancer for Srd5a1. found Srd5a1 mRNA increased 8-fold methylation same CpGs decreased upto 75% between post-natal days (PND) 10-30. Estradiol (E2) levels rise during pre-pubertal stage, exposure cells E2 expression. Chromatin immunoprecipitation (ChIP) an cell line confirmed ESR1 binding differentially-methylated genomic region, also enrichment modification, H3K4me1. Targeting dCas9-DNMT3 CpG2 2.5-fold abolished response E2. In POA, 70% PND 7-10 then remained constant without correlation CpG levels. did not respond GT1-7 cells, even dCas9-TET1 reduced CpG1 by 50%. The neonatal drop POA occurs time increasing glucocorticoids, treatment with dexamethasone levels, ChIP GR enhancer. Our findings on tissue-specific regulation control illuminate epigenetic mechanisms underlying reproductive phenotypic variation which impact life-long health.