2014.5.14，Professor Sun Fei Published a paper entitled:“Transactivation of miR-320 by miR-383 regulates granulosa cell functions by targeting E2F1 and SF” in The Journal of Biological Chemistry，online
Author：Yin Mianmian、Wang Xiaorong、Yao Guidong、Lv Mingrong、Liang Meng、Sun Yingpu、Sun Fei
Abstract：
Our previous studies have shown that miR-320 is one of the most down-regulated miRNAs in mouse ovarian granulosa cells (GCs) after TGF-β1 treatment. However, the underlying mechanisms of miR-320 involved in GC function during follicular development remain unknown. In this study, we found that PMSG treatment resulted in the suppression of miR-320 expression in a time-dependent manner. miR-320 was mainly expressed in GCs and oocytes of mouse ovarian follicles in follicular development. Overexpression of miR-320 inhibited estradiol (E2) synthesis and proliferation of GCs through targeting E2F1 and SF-1. E2F1/SF-1 mediated miR-320-induced suppression of GC proliferation and of GC steroidogenesis. FSH down-regulated the expression of miR-320 and regulated the function of miR-320 in mouse GCs. miR-383 promoted the expression of miR-320 and enhanced miR-320-mediated suppression of GC proliferation. Injection of miR-320 into the ovaries of mice partially promoted the production of testosterone and progesterone, but inhibited E2 release in vivo. Moreover, the expression of miR-320 and miR-383 was up-regulated in the follicular fluid of polycystic ovarian syndrome (PCOS) patients, while the expression of E2F1 and SF-1 was down-regulated in GCs. These data demonstrated that miR-320 regulates the proliferation and steroid production by targeting E2F1 and SF-1 in the follicular development. Understanding the regulation of miRNA biogenesis and function in the follicular development will potentiate the usefulness of miRNA in the treatment of reproduction and some steroid-related disorders.

DOI: 10.1074/jbc.M113.546044