杂种优势是生命科学领域里的热点话题，在作物育种改良中起到重要作用，但其分子机理知之甚少。最近，申请者及其他研究小组证明，染色质重塑因子DDM1对杂种优势的形成至关重要。前期工作中，我们已初步验证了组蛋白修饰在DDM1杂种优势调控中起到关键作用，发现DDM1相关表观调控因子HOG1影响杂种优势的形成。本项目拟：1）通过鉴定DDM1基因组结合位点和DDM1相互作用蛋白深入解析DDM1调控表观遗传学修饰的机制；2）利用不同DDM1遗传背景的材料，通过机器学习鉴定杂种优势相关基因；3）分析DDM1对大豆杂种优势的影响，从而深入解析DDM1调控杂种优势形成的表观遗传学机制。该项目的研究成果对于阐明植物杂种优势的形成机理有重大意义，对于杂种优势在作物育种上的预测及应用有重要指导意义。

Although, during the last centuries, hybrid vigor or heterosis was a hot topic with various hypotheses about it in biology community and widely applied in staple crops breeding, the mechanism remains unclear and debated. Recently, we found that chromatin remodeler DDM1 is a key regulator of growth hybrid vigor in Arabidopsis thaliana early development stage, which is thereafter confirmed by other research group independently. To clarify the mechanisms of DDM1 promoting hybrid vigor, we have proved DDM1 involved in hybrid vigor establishments by regulating H3K4me3 and H3K27me3 modifications, uncovered the effects of HOG1, a DDM1 correlated epigenetic regulator, on growth hybrid vigor. In this project, we will figure out the mechanisms of DDM1 controlling epigenetics modifications by identifying DDM1 targeted genomic regions and DDM1 interacted proteins, uncover the hybrid vigor related genes by machine learning approach, and investigate the effect of DDM1 on hybrid vigor performances in soybean. Our findings will provide novel insights into the molecular mechanisms of hybrid vigor regulations in plants, and also be very helpful to prediction and practice of hybrid vigor in crop breeding.