BAD基因调控绵羊季节性发情启动的机制研究

项目名称： BAD基因调控绵羊季节性发情启动的机制研究

项目编号： No.31501926

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 畜牧学与草地科学

项目作者： 王翔宇

作者单位： 中国农业科学院北京畜牧兽医研究所

项目金额： 19万元

中文摘要： 多数绵羊为季节性发情品种，在夏末秋初开始发情，一年只能繁殖一胎。因此，要增加胎次，启动非繁殖季节发情尤为重要。本课题组前期卵巢转录组测序结果显示，胰岛素通路中BAD基因只在发情前期高表达，其主要功能在医学和模式动物领域已较为明确，但与绵羊发情启动的关系尚不清楚，因此提出胰岛素调控卵巢中BAD基因影响发情启动的科学假设。本项目将以不同发情类型（常年发情和季节性发情）绵羊为研究对象，研究不同繁殖状态下（休情期、发情前期、发情期和发情间期）外周血中胰岛素及性激素浓度变化规律；分析卵巢组织和胰岛素诱导的颗粒细胞中BAD基因及胰岛素通路关键基因表达量；探索BAD基因表达水平变化对颗粒细胞激素分泌和凋亡的影响。在群体和细胞水平阐明不同发情类型的绵羊中胰岛素调控BAD基因发情启动的作用机制，验证并阐释本课题组提出的科学假设，初步揭示季节性发情启动的遗传基础，为增加绵羊胎次及新品种培育提供理论基础。

中文关键词： 绵羊；卵巢；胰岛素信号通路；BAD基因；季节性发情启动

英文摘要： The breeding season of the most domestic ewes normally begins at some point following the summer solstice, and the period of anestrus normally begins in late winter or early spring. Due to a rather long anestrous period it is usually only possible for an ewe to give birth once per year. It is important to know the mechanisms of the onset of estrus in order to increase the fertility of ewes and to obtain lambs twice in one year or three times in two years. The preliminary RNA-Seq of our group revealed that BAD gene was differentially expressed in the different reproductive status between two breeds of sheep and enriched in insulin signaling pathway. It is relatively explicit that BAD gene plays an important role in mediating communication from different upstream signal (insulin) transduction pathways to the Bcl-2 regulated apoptotic decision step in the field of medicine and model animals, but the mechanism of how does it regulate the onset of seasonal estrus in Sheep remains unclear, so we put forward a scientific hypothesis that BAD gene enriched in insulin signaling pathway regulate the onset of seasonal estrus in sheep. In this project, the concentration of hormones in peripheral blood will be tested，the expression pattern of the BAD gene and the other important genes in this pathway and the BAD phosphorylation in ovary will be analyzed in the anestrus, proestrus, estrus and diestrus of Small Tail Han sheep (year-round estrus) and Tan sheep (seasonal estrus). The association between hormone level of insulin and BAD gene expression will also be determined in cultured granulosa cells to test the function of BAD in ovarian. The role and molecular mechanism of BAD gene in insulin signaling pathway regulating the onset of seasonal estrus will be elucidated according to the results in in vivo and in vitro, thus validating and elucidating of our scientific hypothesis. The genetic basis onset of sheep seasonal estrus will be preliminary revealed, this will provide theoretical basis for improvement of lambs production and cultivating of new sheep breeds in China.

英文关键词： Sheep; Ovary;Insulin signaling pathway ;BAD gene;Onset of seasonal estrus