MiR-98 regulates proliferation, apoptosis, and estrogen secretion in goat ovarian granulosa cells by targeting COL1A1

Ovarian Granulosa Cells (OGCs) provide nutrients to oocytes by expressing and secreting follicle-stimulating hormone receptors and regulate the entire follicular development, oocyte maturation and ovulation process. It has been found that COL1A1 and miRNAs play important roles in the proliferation, migration and apoptosis of goat OGCs. However, the specific miRNAs involved in regulating these processes remain unknown. The aim of this study is to investigate the effects of miRNA-targeted regulation of COL1A1 on cell proliferation, migration, apoptosis and hormone secretion in goat OGCs. We used computational biology to predict the miRNAs that target and regulate COL1A1 expression in goat OGCs. We detected the expression of candidate miRNAs in the ovary by fluorescence quantitative PCR and identified the optimal miRNAs that regulate the expression of COL1A1; we then used the dual-luciferase reporter gene assay to test the targeting and regulating effects between miRNAs and COL1A1. Finally, we used the CCK-8, cell scoring, flow cytometry and other assays to test the targeting and regulating effects of COL1A1. We used cell scratch, flow cytometry, Western blot, qRT-PCR, and ELISA to detect the effects of miRNAs on cell proliferation, cell migration, cell cycle, apoptosis, and hormone secretion of OGCs. Computational biology methods predicted that miR-29d-3p, miR-31, miR-98, miR-218 and miR-133 could target and regulate the COL1A1. Compared with the other four miRNAs, miR-98 was extremely significantly down-regulated in the ovarian tissues of ewes with consecutive single lambs in Guizhou Black Goats. It targets and inhibits the expression of the COL1A1. The functional study of miR-98 revealed that the overexpression of miR-98 in the OGCs significantly inhibited the cell proliferation and cell migration, and promoted the early apoptosis Overexpression of miR-98 not only blocked the normal cell cycle, but also inhibited the secretion of E2 by OGCs. This study revealed the regulatory role of miR-98 in the proliferation, migration, apoptosis, and hormone secretion of OGCs in Guizhou Black Goats by targeting COL1A1.This lays the foundation for further exploring the effects of non-coding RNAs on the reproductive ability of black goats, and the effect of non-coding RNAs on the reproductive ability of Guizhou black goats.