植物活性氧诱导钙信号的分子机制研究

项目名称： 植物活性氧诱导钙信号的分子机制研究

项目编号： No.31301000

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 倪君

作者单位： 杭州师范大学

项目金额： 25万元

中文摘要： 植物处于不断变化的环境之中，而环境中的各种胁迫会导致植物体内活性氧的迅速积累。活性氧过去一般被认为是植物代谢过程中产生的毒副产物，然而近年来的研究表明，活性氧还是细胞信号转导和调控的重要组成部分。其中活性氧的一个重要功能是诱导体内游离钙离子（[Ca2+]i）的迅速增加，而钙离子作为胞内第二信使，在细胞信号转导过程中发挥着极其重要的作用。虽然活性氧诱导[Ca2+]i增加的现象早已被发现，但其中的分子机制尚不清楚。本项目利用水母发光蛋白结合钙离子后能发出荧光的特性，建立了一套筛选体系来研究H2O2诱导[Ca2+]i增加的分子机制。目前已经利用该体系筛选出相应的拟南芥T-DNA插入突变体，并克隆到一个基因HICI1。本项目拟通过分子、细胞及电生理等各种手段研究该基因的功能，阐明HICI1在植物感受活性氧及调节细胞内[Ca2+]i的作用机理，为完全揭示活性氧诱导钙信号的分子机制奠定基础。

中文关键词： 钙离子；水母素；活性氧；盐；氨基酸

英文摘要： Plants are constantly subjected to a changing environment, many environmental stresses result in increased generation of active oxygen species (ROS) in plant cells. ROS were considered to be toxic by-products of aerobic metabolism in plants. However, recent studies showed that they also act as important cellular signalling elements. One target of ROS signal transduction is the activation Ca2+-permeable channels, leading to a transient increase in [Ca2+]i. Ca2+ has a second messenger function in the signal production of a cellular response that controls a diverse range of cellular processes. Although the phenomenon that ROS can induce [Ca2+]i, has been proposed for many years, the underlying molecular mechanisms are still unknown. Here, based on the characteristic of aequorin, we established a genetic screening system to study the molecular mechanism of H2O2 induced [Ca2+]i increase. Using this system, we have isolated several Arabidopsis T-DNA insertion mutants, and successfully cloned one gene, HICI1. We plan to study the molecular, cellular and electric physiological functions of the gene, and clarify the molecular roles of HICI1 in perception and transduction ROS signalling, and finally provide strategies in understanding the molecular bases of H2O2 induced [Ca2+]i increase.

英文关键词： calcium ion；aequorin；active oxygen species；salt；amino acid