拟南芥DIF（DRIP1-Interacting Factor）在胁迫信号应答中的功能分析

项目名称： 拟南芥DIF（DRIP1-Interacting Factor）在胁迫信号应答中的功能分析

项目编号： No.31200202

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 微生物学、植物学

项目作者： 辛海波

作者单位： 中国科学院植物研究所

项目金额： 22万元

中文摘要： 拟南芥DREB2A互作蛋白DRIP1属于RING类单亚基泛素化E3连接酶，它通过泛素化DREB2A这个水分胁迫应答途径中的关键转录因子，负调控植物对水分胁迫的响应。但它是如何感知信号，其E3连接酶活性的调控机理尚不清楚。本研究通过基因芯片数据和酵母双杂交实验筛选到了一个干旱前期表达上调的基因，它编码的蛋白与DRIP1在酵母中有较强的互作，命名为DIF(DRIP1-Interacting Factor)。qPCR实验表明，除干旱外，DIF在ABA、NaCl和冷处理表达量明显上调。本研究通过生物化学、遗传学、细胞生物学方法研究DIF对DRIP1活性的调控，揭示DIF参与的DRIP1 E3泛素化反应调控的水分胁迫应答机制和其对其它胁迫信号的应答过程。本研究将有可能发现逆境信号传递过程中新的信号因子，加深人们对植物逆境信号感知和传递的认识。

中文关键词： 干旱；信号传递；蛋白修饰；基因表达；泛素化

英文摘要： As a single-subunit E3 ligase, DRIP1 (DREB2A-Interacting Protein 1) regulates negatively plant response to water stress through DREB2A, which is a key transcription factor in regulating water stress signaling in Arabidopsis. There are still questions of how DRIP1 senses the signaling and how DIRP1 activity is regulated. In this assay, RNA microarray and yeast two-hybrid system were used for gene screening. One gene was used for further analysis because of both its up-regulated expression in early drought stress and the interaction between its encoded protein and DRIP1, and was designated as DIF (DRIP1-Interacting Factor). Real-time PCR assay displayed that DIF was up-regulated by ABA, NaCl and cold besides drought, which implies that, on one side, DIF may be involved in water stress response by transcriptional DREB2A by its regulation of DRIP1; one the other hand, DIF may also be involved in other stress response besides water stress. In this study, biochemics, genetics and cell biology were applied to analyze the regulation of DIF on DRIP1 E3 activity, explain the mechanism of how DIF is involved in water stress response by ubiquitination and display which additional stress signals DIF responses to. In the course of exploring, new signals should be discovered in the stress signal pathway and a knowledge of stre

英文关键词： Drought；signal transduction；protein modification；gene expression；ubiquitination