高等植物胚后的生长发育以及作物的产量依赖于胚胎发生，早期胚胎发生所形成的分生组织是植物胚后发育中各器官形成的源泉和基础，因而研究植物的胚胎发生具有重要理论意义和生产应用价值。本课题组在前期研究结果中发现AtMMS21影响了种子发育、胚根的发生、根尖和茎尖分生组织的形成以及晚期胚胎发育，表明AtMMS21在早期胚胎发生时期就已经参与了拟南芥胚胎发生的调控。本项目拟在前期研究的基础上综合运用细胞生物学、分子生物学、遗传学、生物化学和植物生理学等技术深入分析AtMMS21在植物胚胎发生中的功能，解析AtMMS21调控胚胎发生的细胞和分子机制，并利用酵母双杂交、亲和纯化、BiFC等方法筛选和鉴定与AtMMS21相互作用的蛋白，以期深入阐明AtMMS21介导的SUMO化修饰调控胚胎发生的分子调控网络。项目的实施将阐明一种新的植物胚胎发生调控机制，同时也能为农作物的分子设计育种提供理论依据和基因资源。

The postembryonic growth and development, as well as the crop yields of the higher plants, all depend on the early embryogenesis. The meristems formed in the early embryo are the source and basis of all type of organs in the postembryonic development. Therefore, the study of plant embryogenesis has important theoretical significance and application value. Based on the preliminary findings, AtMMS21 plays important roles in the seed development, radicle initiation, root apical meristem and shoot apical meristem formation and maintenance. And the late embryo of the mms21-1 mutant showed severe defects. These findings suggested that AtMMS21 plays important roles on the embryogenesis from the early embryo stages. The present project intends to analysis the function of AtMMS21 in the embryogenesis, the cellular and molecular mechanisms of the AtMMS21 in regulating the embryogenesis, by comprehensively using the technology of the cell biology, molecular biology, genetics, biochemistry and plant physiology, on the basis of the preliminary findings; and to screen and identify the interactional protein of AtMMS21 through the methods of yeast two-hybrid, affinity purification, BiFC and so on; to elucidating the molecular network of the AtMMS21-mediated SUMO modification in the regulation of embryogenesis.The final results obtained in the proposed research will clarify a novel mechanism regulating the plant embryogenesis and provide the theoretical basis and genetic resource for molecular breeding of crops.