Ghd7基因参与优良杂交稻单亲基因表达调控的分子机理研究

杂种优势的利用极大的提高了全球作物产量。杂种优势机理的解析一直是生命科学领域研究的热点和挑战。科学家们从遗传学角度研究杂种优势已经有一百多年。近些年来，随着高通量测序技术的发展和应用，杂种优势的基因组学基础已经被初步阐明。单亲表达基因是指只在一个亲本和杂种中表达，而在另一个亲本中不表达的基因。杂种中的单亲表达基因形成互补性，可能产生优势，但是机理仍不清楚。本研究以优良杂交稻汕优63为研究对象，利用RNA-seq数据结合两亲本的高质量参考基因组，鉴定单亲表达基因和表达模式，构建共表达网络，以参与水稻光周期调控开花的重要因子Ghd7为例，筛选单亲表达基因Ghd7的调控网络，并且验证其调控靶基因和互作蛋白，解析Ghd7调控水稻产量性状的分子机理，并且初步阐明单亲表达基因的互补性对于杂种优势的影响，为杂种优势利用开拓思路。

Utilization of heterosis has greatly elevated crop productivity globally. Elucidation of biological mechanism of heterosis remains a hot topic and challenge among life science fields. The genetic basis of heterosis has been studied for over one hundred years. With the development and application of high-throughput sequencing technologies, the genomic basis of heterosis was elucidated preliminarily. Single-parent expression represents genes express only in one parent and hybrid but not in the other parent. In hybrid, single-parent expression gives rise to complementation that may contribute to heterosis; however, the mechanism involved remains elusive. In this proposal, we conceive to align RNA-seq data with two parental high-quality reference genomes, identify single-parent expression and expression patterns, and construct co-expression networks, using an elite hybrid Shanyou 63 as a model. Ghd7, showing single-parent expression in Shanyou 63, plays a vital role in photoperiodic flowering in rice. We screen Ghd7-involved co-expression network and verify its targeted genes and interacting proteins. We anticipate that this proposed study will illustrate the molecular mechanism of Ghd7 regulating yield traits in rice, and preliminarily advance our understanding of how complementation contributes to heterosis. It is also expected that the outcome of the project will provide useful information for further applications in heterosis breeding.