Identification of ID1 and miR-150 interaction and effects on proliferation and apoptosis in ovine granulosa cells.

Granulosa cells (GCs) proliferation and apoptosis play a significantly role in follicular development and atresia. ID1 and miR-150 are involved in cell apoptosis and follicular atresia, but the interaction and function of ID1 and miR-150 in GCs are unclear. This study focuses on ID1 and miR-150 in terms of the interaction and effects on proliferation and apoptosis in ovine granulosa cells. Our findings revealed that ID1 decreased the promoter activity and expression level of oar-miR-150. However, the expression of ID1 was downregulated by miR-150, and ID1 was identified as a target gene of oar-miR-150. miR-150 mimic inhibited proliferation and upregulated apoptosis rate in ovine GCs, while the results of miR-150 inhibitor were opposite. Overexpression of ID1 significantly inhibited ovine GCs proliferation and cell cycle-related genes (CDK1, CDK2, CDK4, CCND2, CDC20, and PCNA) expression, whereas knockdown of ID1 promoted cell proliferation and those genes expression. Overexpression of ID1 significantly downregulated mitochondrial membrane potential and Bcl-2 expression in ovine GCs, and upregulated the expression of pro-apoptosis genes Bax, Caspase-3, and Caspase-9, whereas the results of ID1 knockdown were reversed. Collectively, these findings indicate the interaction and the vital role of ID1 and miR-150 on proliferation and apoptosis in ovine granulosa cells, which may suggest a novel target for ovine follicular development and atresia.