The transcription factor SMAD4 and miR-10b contribute to E2 release and cell apoptosis in ovarian granulosa cells by targeting CYP19A1

• Published in: Molecular and cellular endocrinology 2018-11, Vol.476, p.84-95
• Main Authors: Li, Qiqi, Du, Xing, Pan, Zengxiang, Zhang, Lifan, Li, Qifa
• Format: Article
• Language: English
• Subjects: 3' Untranslated Regions - genetics; Animals; Apoptosis; Aromatase - genetics; Aromatase - metabolism; Base Sequence; Binding Sites; CYP19A1; Estradiol - metabolism; Female; Granulosa cell apoptosis; Granulosa Cells - cytology; Granulosa Cells - metabolism; MicroRNAs - genetics; MicroRNAs - metabolism; miR-10b; Nucleotide Motifs - genetics; Pig; Promoter Regions, Genetic - genetics; Protein Binding - drug effects; RNA, Messenger; SMAD4; Smad4 Protein - metabolism; Swine
• ISSN: 0303-7207; 1872-8057
• DOI: 10.1016/j.mce.2018.04.012

The cytochrome P450 family 19 subfamily A member 1 (CYP19A1) gene, encodes aromatase, a key enzyme in estradiol (E2) synthesis, and is down-regulated during porcine follicular atresia. However, its role in and the mechanism of transcriptional repression in follicular atresia is largely unknown. In the present study, we show that the CYP19A1 gene stimulates E2 release and inhibits cell apoptosis in porcine granulosa cells (GCs). SMAD4, an anti-apoptotic moderator, was identified as a transcription factor of the porcine CYP19A1 gene and enhanced the expression and function of CYP19A1 in porcine GCs through direct binding to a SMAD4-binding element (SBE) within the promoter region of CYP19A1 gene. Moreover, we found that miR-10b, a pro-apoptotic factor, directly interacted with 3′-UTR of the porcine CYP19A1 mRNA, inhibiting its expression and function in porcine GCs. Collectively, we demonstrated that CYP19A1 is an inhibitor of follicular atresia and is regulated by both SMAD4 and miR-10b. These findings provide further insight into the mechanisms of CYP19A1 in steroid hormone synthesis and GC apoptosis and provide molecular targets for exploring methods of treatment for steroid-dependent reproductive disorders. •CYP19A1 suppresses porcine GCs apoptosis through controlling E2 release.•SMAD4 promotes CYP19A1 transcription by directly binding to its promoter.•SMAD4-CYP19A1 axis enhances E2 synthesis and prevents porcine GC apoptosis.•miR-10b impairs CYP19A1 expression and functions by targeting its 3′-UTR region.