镉诱导表达的水稻转运蛋白的功能研究

项目名称： 镉诱导表达的水稻转运蛋白的功能研究

项目编号： No.31470443

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 陈彩艳

作者单位： 中国科学院亚热带农业生态研究所

项目金额： 85万元

中文摘要： 日益严重的稻田镉污染威胁着我国生态安全和食品安全，培育低镉积累品种以降低稻米镉含量，或者培育耐镉品种以用于植物修复是防治稻田镉污染的理想手段。阐明水稻对镉的吸收和转运的分子机理是培育低镉品种和耐镉品种的前提，但是已有的分子生物学研究成果还不能全部解释水稻对镉的吸收、转运、外排以及螯合等生物学过程，不能满足低镉、耐镉水稻分子育种的需要。在前期水稻镉胁迫转录组研究中，我们鉴定出了39个镉诱导表达的转运蛋白基因。本项目拟以此为基础，1）筛选能显著改变镉吸收、转运、隔离或外排能力的镉诱导转运蛋白基因；2）研究它们的生理生化功能，阐明其参与镉胁迫响应的分子机理；3）探索多个基因的组合利用来降低稻米镉含量和/或增加水稻镉抗性的可行性。可预期的研究成果能完善人们对水稻镉胁迫响应机制的理解，为水稻低镉或耐镉育种提供基因资源，从提高作物抗镉污染风险的角度探索生态修复土壤镉污染的理论基础。

中文关键词： 镉；水稻；转运蛋白；分子机制

英文摘要： Rice, a staple crop for more than half of the population in the world, is also a promising candidate for Cd phytoremediation. With the Cd pollution increase, it is necessary to lower Cd levels in grain for food safety and raise Cd-resistance for phytoremediation. So far a limited number of genes has been identified to be responsible for Cd uptake, transportation, compartmentation or sequestration, which is a prerequisite for genetic improvement of Cd accumulation and resistance. The research proposed herein aims to isolate genes involved in Cd accumulation and/or resistance from 39 transporters that have been identified to be Cd-responsive. We will first characterize their knockout mutants, RNA interference lines and overexpression plants to identify genes that are required for rice Cd resistance and grain Cd accumulation. Then the subcellular location of candidate genes and their element specificity for transportation will be studied using protoplast transportation assay and yeast metal resistance analysis. After that, double mutants or triple mutants will be developed to study the interaction among these genes in genetic control of Cd accumulation and resistance. The success of this project will benefit both breeding of Cd-pollution safe rice and Cd phytoremediation, thus facilitating the rapid development of rice as a model plant to be adopted in ecological management of soil Cd pollution.

英文关键词： Cadmium;rice;transporter;molecular mechanism