title: Dynamic Changes in the Follicular Transcriptome and Promoter DNA Methylation Pattern of Steroidogenic Genes in Chicken Follicles throughout the Ovulation Cycle.
abstract: The molecular mechanisms associated with follicle maturation and ovulation are not well defined in avian species. In this study, we used RNA-seq to study the gene expression profiles of the chicken follicles from different developmental stages (pre-hierarchical, pre-ovulatory and post-ovulatory). Transcriptomic analysis revealed a total of 1,277 and 2,310 genes were differentially expressed when follicles progressed through the pre-hierarchical to hierarchical and pre-ovulatory to post-ovulatory transitions, respectively. The differentially expressed genes (DEG) were involved in signaling pathways such as adherens junction, apoptosis and steroid biosynthesis. We further investigated the transcriptional regulation of follicular steroidogenesis by examining the follicle-specific methylation profiles of Star (steroidogenic acute regulatory protein), Cyp11a1 (cytochrome P450, family 11, subfamily a, polypeptide 1) and Hsd3b (hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 1), genes encoding the key enzymes for progesterone synthesis. The varied patterns of DNA methylation in proximal promoters of Star and Cyp11a1but not Hsd3b in different follicles could play a major role in controlling gene expression as well as follicular steroidogenic activity. Finally, the promoter-reporter analysis suggests that TGF-β could be involved in the regulation of Hsd3b expression during ovulation. Together, current data not only provide novel insights into the molecular mechanisms of follicular physiology in chicken follicles, but also present the first evidence of epigenetic regulation of ovarian steroidogenesis in avian species.
authors.affiliation: Department of Biology Science and Technology, Taishan University, Taian 271021, China.|Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian 271018, China.
authors.forename: Guiyu
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Department of Gynecology, Taian Materal and Child Health Hospital, Taian 271021, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Mao
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian 271018, China.
authors.forename: Wendi
authors.initials: W
authors.lastname: Zhou
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian 271018, China.
authors.forename: Yunliang
authors.initials: Y
authors.lastname: Jiang
mesh_terms: D000818:Animals; D002645:Chickens / Q000378:metabolism / Q000502:physiology; D019175:DNA Methylation / Q000502:physiology*; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology; D006080:Ovarian Follicle / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D010060:Ovulation / Q000378:metabolism / Q000502:physiology*; D011374:Progesterone / Q000096:biosynthesis*; D011401:Promoter Regions, Genetic; D060888:Real-Time Polymerase Chain Reaction; D059467:Transcriptome / Q000235:genetics / Q000502:physiology; D016212:Transforming Growth Factor beta / Q000502:physiology
chemical_list: D016212:Transforming Growth Factor beta; D011374:Progesterone