The Arabidopsis NPR1 disease resistance protein is a novel cofactor that confers redox regulation of DNA binding activity to the basic domain/leucine zipper transcription factor TGA1
The Arabidopsis NPR1 disease resistance protein is a novel cofactor that confers redox regulation of DNA binding activity to the basic domain/leucine zipper transcription factor TGA1
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DOI：
10.1105/tpc.012849
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发表时间：
2003-09-01
期刊：
影响因子：
11.6
通讯作者：
Fobert, PR
中科院分区：
文献类型：
--
作者：
Després, C;Chubak, C;Fobert, PR
拟南芥NPR 1蛋白在系统获得抗性过程中对调节水杨酸依赖性基因表达至关重要。NPR 1与TGA类基本结构域/Leu拉链转录因子的成员差异地相互作用，并调节其DNA结合活性。在这里，我们报告说，虽然TGA 1不与NPR 1在酵母双杂交试验，水杨酸处理诱导这些蛋白质之间的相互作用在拟南芥叶片。这种现象与TGA 1 Cys残基的减少有关。此外，TGA 1 Cys-260和Cys-266的定点突变使得能够在酵母和拟南芥中与NPR 1相互作用。总之，这些结果表明，TGA 1依赖于Cys残基的氧化态来介导与NPR 1的相互作用。TGA 1中的分子内二硫键排除了与NPR 1的相互作用，并且NPR 1只能刺激还原形式的TGA 1的DNA结合活性。与其动物和酵母对应物不同，TGA 1的DNA结合活性不受氧化还原调节;然而，这种性质是通过与NPR 1辅因子相互作用而赋予的。
The Arabidopsis NPR1 protein is essential for regulating salicylic acid-dependent gene expression during systemic acquired resistance. NPR1 interacts differentially with members of the TGA class of basic domain/Leu zipper transcription factors and regulates their DNA binding activity. Here, we report that although TGA1 does not interact with NPR1 in yeast two-hybrid assays, treatment with salicylic acid induces the interaction between these proteins in Arabidopsis leaves. This phenomenon is correlated with a reduction of TGA1 Cys residues. Furthermore, site-directed mutagenesis of TGA1 Cys-260 and Cys-266 enables the interaction with NPR1 in yeast and Arabidopsis. Together, these results indicate that TGA1 relies on the oxidation state of Cys residues to mediate the interaction with NPR1. An intramolecular disulfide bridge in TGA1 precludes interaction with NPR1, and NPR1 can only stimulate the DNA binding activity of the reduced form of TGA1. Unlike its animal and yeast counterparts, the DNA binding activity of TGA1 is not redox regulated; however, this property is conferred by interaction with the NPR1 cofactor.