植物类受体激酶FLS2内吞途径的研究

植物内吞作用不仅维持着胞外物质吸收和胞内蛋白运输的平衡，而且在植株的生长发育中起重要作用。然而，有关植物细胞的内吞方式和分子机制尚缺乏深入的研究。植物类受体激酶FLS2经配体刺激特异性地进行内吞，是研究植物细胞内吞作用理想的目标蛋白。本项目针对前人工作的不足，我们将以拟南芥为材料，着重展开三方面的研究：(1)观察类受体激酶FLS2经配体刺激前后在质膜上的分布模式并测定相关动力学参数；(2)研究类受体激酶FLS2与内吞相关蛋白clathrin、flotillin在质膜上的共定位；(3)揭示内吞相关蛋白在类受体激酶FLS2内吞进入胞质中的作用。在本项目研究中，拟采用包括可变角度的全内反射荧光显微术、荧光相关光谱、荧光交叉相关光谱等一些新方法、新技术，借助这些新技术和新方法，旨在揭示笼型蛋白和脂筏在FLS2内吞过程中的作用，从而阐明FLS2的内吞模式，为进一步研究植物内吞作用的分子机理奠定基础。

The endocytosis in plant cells maintains the uptake of molecules into cells and the turn over of intracellular protein trafficking, therefore it is essential for the plant development. However, the endocytic pathways and regulatory mechanism remain to be further investigated. The receptor-like kinase FLAGELLIN -SENSITIVE2 (FLS2), which internalizes specifically only under the ligand induction, is one of ideal proteins for analysis of plant endocytosis. In the present study, we will investigate the endocytic pathways of receptor-like kinase FLS2 in Arabidopsis as well as its molecular mechanism of internalization by means of dynamic analysis in the living cells together with genetic approaches. First, we will analyze the distribution patterns and dynamic characteristics of FLS2 before and after the ligand induction in plasma membrane. Then, we will determine the co-localization between FLS2 and endocytosis-associated proteins clathrin or flotillin in plasma membrane. Finally, we will further explore the function of endocytosis-associated proteins in the internalization of FLS2 into cytoplasm. In the course of the investigation, some new methods and techniques including variable-angle total internal reflection fluorescence microscopy, fluorescence correlation spectroscopy, fluorescence cross-correlation spectroscopy will be used in this study with the aim of uncovering the function of clathrin and lipid raft protein flotillin in the endocytosis of FLS2 receptor and revealing the mode of FLS2 endocytosis under the ligand induction. Surely, the results of this study will lay foundation for the further investigation of molecular mechanism for plant endocytosis.