籼粳稻间硝态氮吸收利用差异的分子机制研究

项目名称： 籼粳稻间硝态氮吸收利用差异的分子机制研究

项目编号： No.31500975

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 生物科学

项目作者： 胡斌

作者单位： 中国科学院遗传与发育生物学研究所

项目金额： 20万元

中文摘要： 籼稻与粳稻是现代栽培稻的两个主要亚群。相比粳稻，籼稻通常表现出更高的氮肥利用效率，分离鉴定控制品种间氮利用差异的基因位点对提高粳稻氮肥利用效率具有重要意义。我们基于176份水稻品种基因组重测序数据及氯酸盐（硝酸盐毒性类似物）敏感性测定，通过基因组关联分析（GWAS）鉴定到多个可能的氮高效吸收利用候选位点, 并对其中一个重要位点，CHR1，进行了初步研究。CHR1在籼粳亚群间呈现规律性分化，且与氯酸盐敏感性呈极高的关联性。研究表明，CHR1受硝酸盐诱导并表现出硝酸盐转运蛋白活性，且籼稻型活性高于粳稻型，暗示CHR1基因的变异可能是导致籼粳稻间硝态氮利用差异的重要原因之一。本项申请拟在此基础上，进一步深入研究CHR1在硝态氮利用中的功能及导致籼稻型CHR1活性升高的原因，揭示籼粳稻间硝态氮利用效率差异的分子机制，并探索CHR1对于提高水稻氮肥利用效率的应用价值。

中文关键词： 作物；基因克隆；突变体；基因表达调控

英文摘要： Japonica and Indica are two major subpopulation of Asian cultivated rice and the Indica variety usually shows higher nitrogen use efficiency (NUE). Isolation of the related gene loci will hold great promise to improve the NUE in rice breeding; however, due to the difficulty in phenotyping, it is still a challenging task. By re-sequencing 176 rice cultivars and performing chlorate (the toxic analog of nitrate) sensitivity investigation, we carried out genome-wide association study (GWAS) and several potential high NUE loci were identified, one of which, named CHR1, was preliminarily studied. CHR1 diverges between Indica and Japonica and the chlorate sensitivity also highly associated with allelic variation of CHR1. CHR1 is nitrate inducible and displays nitrate transport activity. Moreover, CHR1-Indica type exhibited higher nitrate transport activity than CHR1-Japonica type, suggesting the mutation of CHR1 is probably responsible for nitrate usage differentiation between Japonica and Indica. Based on these results, this project attempts to study the detailed function of CHR1 in nitrate uptake/transport and the molecular basis for the inceeased nitrate transport activity of CHR1-Indica, illustrate the molecular mechanism of nitrate use efficiency differentiation between Japonica and Indica, and investigate the possible application of CHR1 in NUE improvemt of rice.

英文关键词： crops;gene cloning;mutant;gene expression regulation