表观遗传修饰和基因表达与玉米杂种优势关系的研究

项目名称： 表观遗传修饰和基因表达与玉米杂种优势关系的研究

项目编号： No.31471565

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 食品科学、农学基础与作物学

项目作者： 祁新

作者单位： 吉林农业大学

项目金额： 82万元

中文摘要： 杂种优势已在作物生产上广泛利用，但其遗传和分子基础尚不明晰。新近研究表明，杂种优势与基因表达及表观遗传修饰变化（如DNA甲基化和小RNA丰度改变等）有关，但二者与优势表型间的因果关系尚未建立。本项目拟在前期基础上，以DNA甲基化酶编码基因DMT105、DMT106和组蛋白甲基转移酶基因SDG102的玉米转基因沉默系以及以此为基础的正反交杂种为材料，开展分子表观遗传学、基因组学和农学的整合研究，从表观遗传调控和基因表达层面解析玉米杂种优势形成的分子机制。主要研究内容包括：（1）解析DNA甲基化和组蛋白修饰对杂种基因表达，特别是allele-specific 基因表达的影响；（2）建立DNA甲基化、组蛋白修饰、基因表达与杂种产量性状优势之间的因果和相关关系 （3）探讨allele-specific表观遗传修饰与双亲遗传差异之间的可能关系。研究结果可能为玉米杂种优势利用和育种技术创新提供理论依据。

中文关键词： 玉米；杂种优势；表观遗传修饰；基因表达

英文摘要： Heterosis has been widely used in modern crop breeding. However, the genetic and molecular basis underpining heterosis remains mysterious. Recent studies have shown that heterosis is related with novel gene expression and epigenetic remodelling (e.g., DNA methylation and small RNA abundance alterations). Nevertheless, the causality between these and heterosis are unknown. The prosposal is designed to explore their possible intrinsic links. By using maize RNAi inbred lines of DNA methytransferase encoding genes, DMT105 and DMT106, and a histone methytransferse gene, SDG102, and their corresponding reciprocal hybrids, we aimed to combine epigenetics, genomics and phenotyping analyzical tools to address these issues. We will particularly focus on the intrinsic relationship between eigenetic regulation/gene expression and maize heterosis. The main contents include: (1) to analyze the effect of DNA methylation and histone modification on gene expression, especially on allele-specific expression (ASE) in hybrids; (2) to establish the causal or corelative links between DNA methylation, histone modification, gene expression (ASE in particular) and the heterosis of yield-related traits; (3) to explore the possible links between allele-specific epigenetic modification and parental genetic differences. Results obtained from this study are expected to provide new clues for the utilization of heterosis in maize breeding.

英文关键词： Maize;Heterosis;Epigenetic modification;Gene expression