冰叶日中花C3-CAM转换中钙离子介导的信号调控机制

项目名称： 冰叶日中花C3-CAM转换中钙离子介导的信号调控机制

项目编号： No.31201645

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 植物保护学、园艺学与植物营养学

项目作者： 胡增辉

作者单位： 北京农学院

项目金额： 22万元

中文摘要： 具备景天酸代谢途径（CAM）的植物对多种逆境均表现出较高的抗性。本研究以典型的兼性CAM植物-冰叶日中花（Mesembryanthemum crystallinum）为实验材料，以甘露醇、盐处理为诱导手段，利用选择性微电极、激光共聚焦显微镜等技术检测C3-CAM转换过程中，根部和叶片细胞跨膜钙离子信号、活性氧信号、及脱落酸的变化，并通过施加钙离子信号、活性氧信号、以及脱落酸信号的阻断剂，结合应用反转录PCR、Western杂交及液相串联质谱检技术，分别在基因表达、蛋白合成及蛋白磷酸化水平上对CAM途径关键酶-PEPC表达进行测定，研究钙离子信号在C3-CAM转换中的作用，及其在信号调控途径中与活性氧、脱落酸信号的关系，以揭示C3-CAM转换中钙离子介导的信号传递，对查清CAM形成机制有重要意义，并且能为探索提高园林植物抗逆性新方法，通过遗传改良培育高抗逆性的植物新品种提供理论依据。

中文关键词： 冰叶日中花；耐盐机理；钙信号；离子平衡；生理响应

英文摘要： The plants emloying crassulacean acid metabolism (CAM) have high resistance to various stresses. In this study, the typically facility CAM plant, Mesembryanthemum crystallinum was used as plant material. Using selective microelectrode technique, confocal laser scanning microscope technique, etc., the transmembrane calcium ion flux, reactive oxygen species (ROS), and abscisic acid (ABA) in the roots and leaves during the C3-CAM transition indced by mannitol and NaCl treatment were examined. Then combined with the examination of PEPC,a key enzyme of CAM, at three levels of gene expression, protein snysthesis, and protein phosphorylation through RT-PCR, Western blot, and LC-MS/MS, the blockers of calcium ion signal, ROS signal, and ABA signal were exerted to investigate the role of calcium ion in the C3-CAM transition, and the relationship with ROS and ABA in the signal transduction pathway. The study aims to discover the signal transduction miediated by calcium ion in C3-CAM transition of Mesembryanthemum crystallinum, which has great significance for understanding the generation mechanism of CAM. Moreover this study also is benificial to explore the new methods to enhance resistance of landscape plants to stresses, and can provide theoretical basis for cultivating new varieties with high stress resistance through

英文关键词： Mesembryanthemum crystallinum L.；mechanism of salt tolerance；Calcium signal；ion homeostasis；physiological response