根是植物重要的营养器官。植物根的持续的生长和发育是通过具有持续增殖能力的根尖分生组织来维持的，根尖分生组织区细胞分裂活性是主根可塑性生长能力的决定性因素。本研究组在前期的研究中发现SUMO E3连接酶AtMMS21在调控主根分生组织发育中起重要作用，在最近的工作中利用免疫亲和纯化与质谱分析技术并结合酵母双杂交和体外pull down实验验证了染色质重塑因子HMIP1与SUMO E3 连接酶AtMMS21相互作用，且HMIP1的T-DNA插入突变体具有短根的表型。本项目拟在此基础上结合细胞生物学、分子生物学、遗传学和生物化学等方法，鉴定并研究AtMMS21与染色体重塑因子HMIP1互作的生化机制且如何调控植物根发育的分子机理，以期进一步深入理解植物蛋白SUMO化修饰介导染色质重塑调控根发育的分子机制，阐明主根发育的分子调控网络。

Root is an important vegetative organ in plants. The continuous growth and development of root are sustained by the specialized proliferative root apical meristem. The decisive factor of the plastic growth ability of the main root lies in the activity of cell division in the meristem region. Our previous studies showed that the SUMO E3 ligase AtMMS21 plays an important role in the regulation of the main root meristem development. Our recent work also showed that chromatin remodeling factor HMIP1 interact with AtMMS21 by affinity chromatography and mass spectrometry hyphenated techniques combined with yeast two hybrid and in vitro pull-down experiments, and HMIP1 T-DNA insertion mutants with the short root phenotype. On this basis, this project will identify and study the biochemical mechanisms of interaction between AtMMS21and HMIP1 and how to regulate main root development by using methods of cell biology, molecular biology,genetics and biochemistry,and hope to further understand the regulation mechanism of the main root development through chromatin remodeling mediated by SUMOylation and also provide new theoretical basis for clarifing molecular regulatory networks of root development.