miR-107 suppresses porcine granulosa cell proliferation and estradiol synthesis while promoting apoptosis via targeting PTGS2

Abstract

The proliferation, steroid metabolism, and apoptosis of porcine ovarian granulosa cells (GCs) are critical for follicular development. MicroRNAs (miRNAs) are small endogenous RNAs that regulate gene expression post-transcriptionally and modulate signaling networks involved in various cellular processes. In this study, we identify miR-107, a conserved miRNA, as a key regulator of porcine follicle development through its effects on GCs proliferation, steroid metabolism, and apoptosis. Our findings demonstrate that miR-107 suppresses GCs proliferation and estradiol synthesis while promoting apoptosis. Mechanistically, miR-107 exerts its regulatory effects by targeting Prostaglandin-Endoperoxide Synthase 2 (PTGS2), binding to the 3ʹ untranslated region (3ʹ-UTR) of its mRNA. Overexpression of PTGS2 positively regulates porcine GCs function, significantly enhancing cell proliferation and steroid synthesis, reducing apoptosis, and increasing the protein levels of HSD3B1 and CYP19A1, which are key members of the ovarian steroidogenesis signaling pathway. These findings highlight the role of miR-107 in regulating porcine follicular development and underscore its potential as a molecular marker for influencing follicle growth and reproductive efficiency.