生长素极性输出载体PIN内吞与极性定位分子调控机理

项目名称： 生长素极性输出载体PIN内吞与极性定位分子调控机理

项目编号： No.91317304

项目类型： 重大研究计划

立项/批准年度： 2014

项目学科： 微生物学、植物学

项目作者： 潘建伟

作者单位： 浙江师范大学

项目金额： 200万元

中文摘要： PIN介导的生长素极性运输是生长素调控植物生长发育的独特方式。PIN内吞与极性定位是生长素极性运输的重要分子基础。网格蛋白介导的内吞(CME)在PIN极性定位中具有关键性调控作用。根据哺乳动物CME分子机理，植物网格蛋白与接头蛋白AP2互作，而AP2与PIN互作，形成网格蛋白/ AP2/PIN复合物，最终导致PIN内吞，但缺乏直接的实验证据。本申请项目在发现拟南芥网格蛋白轻链CLC调控PIN内吞的基础上，综合运用遗传、细胞、生化等手段，开展以下几项研究工作：（1）PIN2内吞保守基序(AP2识别位点)在PIN2内吞与极性定位中的生物学功能；（2）AP2介导PIN内吞的分子证据及其生物学功能；（3）CME抑制剂A23抑制PIN内吞的作用位点。通过这些研究深层次剖析PIN介导生长素极性运输的分子调控机理，有利于阐明生长素调控植物生长发育的作用机理，期望获得更高层次的原创性研究成果。

中文关键词： 生长素；网格蛋白；内吞；PIN；极性

英文摘要： PIN (PIN-FORMED)-mediated polar auxin transport (PAT) is a unique manner in auxin regulation of plant growth and development. PIN endocytosis and its polar localization are an important molecular mechanism in PIN-mediated polar auxin transport out of the cell. Clathrin-mediated PIN internalization plays a key regulatory role in the establishment of PIN polar localization at the plasma membrane (PM). Based on clathrin-mediated endocytosis (CME) in mammalian cells, the binding of plant clathrin with adaptor protein2 (AP2) and in turn AP2 interaction with PM-localized PIN proteins leads to the formation of clathrin/AP2/PIN complex, and finally PIN endocytosis occurrence. However, experimental evidence is still lacking. Our previous study has revealed that clathrin light chains (CLC) regulate PIN endocytosis. In this study, genetic, cytological, physiological, and biochemical strategies will be used to further analyze molecular mechanisms underlying PIN endocytosis and its PM polar localization in Arabidopsis, which include (1) functional identification of PIN conserved internalization motifs (AP2 specific binding sites) in PIN endocytosis and its PM polar localization; (2) the functional role and molecular mechanisms of AP2-mediated PIN endocytosis; and (3) identification of tyrphostin A23 action targets in the inh

英文关键词： Auxin；Clathrin；Endocytosis；PIN；Polarity