高温诱导尼罗罗非鱼雌鱼性逆转的分子表观机制

项目名称： 高温诱导尼罗罗非鱼雌鱼性逆转的分子表观机制

项目编号： No.31472270

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 农业科学

项目作者： 季相山

作者单位： 山东农业大学

项目金额： 86万元

中文摘要： 罗非鱼雄性生长速度显著快于雌性，一直以来人们都致力于培育高雄/全雄罗非鱼。利用高温诱导下罗非鱼雌鱼能性逆转为生理雄鱼的特点，可以建立一种经济环保的培育高雄/全雄罗非鱼的新方法。但是目前我们对高温诱导罗非鱼雌鱼性逆转的分子表观机制仍认识不够。本项目首先基于组学分析找出高温胁迫下调控罗非鱼雌鱼性逆转的候选基因；根据筛选基因的表达定位等情况选择1-2个基因作为目标基因进一步研究；从高温胁迫下目标基因启动子（顺式作用元件）表观遗传修饰改变和转录因子（反式作用因子）与目标基因启动子结合能力变化2个方面揭示高温诱导调控目标基因表达的分子机理；进一步利用CRISPR/Cas 9技术敲降/敲除目标基因，研究高温对敲降/敲除个体性逆转的影响，从基因功能角度探讨高温胁迫下目标基因调控罗非鱼性逆转的分子机制。本项目不仅为培育高雄/全雄罗非鱼提供理论和技术支持，也有助于揭示温度影响鱼类性别分化的分子机理。

中文关键词： 尼罗罗非鱼；高温；转录组；表观遗传学；基因功能

英文摘要： The Nile tilapia is a species of tilapia, a cichlid fish native to Africa. China is by far the main tilapia producing country, with more than 1 million tonnes production each year. The Nile tilapia shows sexual growth dimorphism and the males grows faster than females. As a result, the development of an all-male Nile tilapia stock would be of significant benefit. Nowadays, we all know that high-temperature can induce the female sex reversal. High-temperature induction could be used as a consumer- and environment-friendly approach to significantly increase the proportion of males in Nile tilapia. However, the molecular and epigenetic mechanisms of high-temperatue inducing sex reversal of Nile tilapia females remains elusive. In this study, the differential expression genes between high-temperature induction and control group will be screeened based on transcriptome and methylome analysis. The cellular localization of selected genes will be effectively demonstrated by in-situ hybridiztion and immunohistological analysis. The protein expression changes of seleceted genes after high-temperature induction will also be analyzed. Based on the the result of protein analysis, 1-2 target genes will be selected and used for further studies. In order to analyze the mechanism behind the expression manipulation of target genes, the changes of methylation level of target genes under high-temperature masculinization will be studied. The binding of transcription factor to DNA promoter regions upstream of gene transcription start sites (TSSs) is one of the most important mechanisms by which gene expression, and thus many cellular processes, are controlled. In this study, we will use ChIP for the analysis of transcription factor binding to the promoter of target genes. In the end, Cas 9 will be used for the editing of target genes. We will investigate the the sex reversal rate of knockdown or knockout individuals under high-temperature masculinization. Collectively, this study is meant to provide theoretical and technical foundation for all-male Nile tialpia stock,and improve the understanding of temperature-dependent sex determination in fish.

英文关键词： Nile tilapia;High-temperature;Transcriptome;Epigenetics;Gene function