高等植物的株型形成与植物形态/作物产量直接相关,长期以来，其分子遗传基础一直是植物生物学的研究热点，2008年新的植物激素独角金内酯（SL）的发现将该领域的研究变得更令人激动。申请人前期工作发现了一个表达水平受低氮抑制的基因GAT，其突变体与SL途径上的max突变体表型相似，参与分枝调控，我们的前期结果表明GAT并不直接参与SL的合成，这可能暗示存在一条潜在的新的分枝调控途径。在此基础上，本项目拟利用分子生物学、细胞生物学、生物化学和蛋白组学等方法，以gat的多分枝表型为研究切入点，首先研究其表达模式和蛋白定位，进而深入研究GAT基因功能，通过酵母双杂、基因芯片数据及蛋白组信息，获得GAT可能的互作分子，探索调控植物株型的分子机制，为更进一步揭示拟南芥株型形成的调控网络提供新知识，也可以为通过分子设计改良植物株型，提高作物产量提供新的思路。

Shoot branching plays an important role in establishing plant architecture during development and growth, also confers to the flexibility for plants to respond to enviromental stresses, therefore, it directly affects plant body plans and crop yields. For a long time, studies on Arabidopsis, tomato, garden pea and crops such as rice and maize have greatly strenghthened the understanding on the molecular genetic bases of shoot branching, which has been one of the hottest areas in plant developmental biology. The finding of strigolactone, a new type of plant hormone first reported in 2008, has been making this field even more exciting. Previous work of the author found that a nitrogen-regulated gene, GAT, is involved in shoot branching control in Arabidopsis; gat mutant shows similar phenotypes with max mutants while MAX genes are involved in strigolactone pathway. The author's further studies showed that GAT is not directly invovled in biosynthesis of strigolactione, and more likely it could embody a new pathway for repression of branching. Based on this research, the current project is going to further investigate GAT gene expression patterns and localization of GAT proteins, meanwhile, use yeast-two-hybrid, gene chips and proteomics information to explore the possible mechanism(s) through which GAT may be involved in shoot branching control. Thus, it will provide new knowledge towards understanding the molecular genetic regulation of plant architectures in Arabidopsis. In the future it may also bring new ideas on genetic modification towards optimizing plant architectures and increasing crop yields.