生物钟基因Bmal1通过Cyp11a1调控母猪卵巢颗粒细胞雌激素合成的分子机制

雌激素与卵母细胞发育和繁殖性能紧密相关。核心生物钟基因Bmal1在大鼠卵巢颗粒细胞中呈现节律性表达，且参与雌激素合成。申请人前期研究显示，干扰猪卵巢颗粒细胞Bmal1导致生物钟系统节律紊乱，雌激素分泌量降低，雌激素合成中的关键酶CYP11A1的表达水平也同时降低。然而，生物钟因子BMAL1作为转录因子对CYP11A1调控的分子机制尚不明晰。因此，本项目借助CRISPR/Cas9基因编辑技术制备颗粒细胞Bmal1敲除/敲入细胞模型，研究猪卵巢颗粒细胞中Cyp11a1在BMAL1调控雌激素合成中的作用；采用ChIP-PCR、RIP、Co-IP和双荧光素酶报告基因分析BMAL1与CYP11A1的作用关系；阐明BMAL1通过CYP11A1对猪卵巢颗粒细胞中雌激素合成的调控机制，为通过生物钟系统调控猪繁殖性能提供理论支撑。

Estrogen is closely related to oocyte development and reproductive performance. The core clock gene Bmal1 is expressed rhythmically in rat ovarian granulosa cells and is involved in estrogen synthesis. Interfering with Bmal1 of porcine ovarian granulosa cells leads to the disturbance of circadian rhythm, the decrease of estrogen secretion. CYP11A1, which is a key enzyme in estrogen synthesis, also decreased. However, the molecular mechanism of BMAL1 as a transcription factor regulating CYP11A1 is unclear. With Bmal1 knock-out / knock-in cell models edited by CRISPR/Cas9 technology, this project aims to explore the role of Cyp11a1 in the process of estrogen synthesis regulated by BMAL1. The relationship between BMAL1 and CYP11A1 was analyzed by using ChIP-PCR, RIP, Co-IP and double luciferase reporter gene. This study will elucidate the regulatory mechanism of BMAL1 on estrogen synthesis through CYP11A1 in porcine ovarian granulosa cells, and to provide theoretical support for regulating porcine reproductive performance through biological clock system.