A single amino acid insertion in the WRKY domain of the Arabidopsis TIR-NBS-LRR-WRKY-type disease resistance protein SLH1 (sensitive to low humidity 1) causes activation of defense responses and hypersensitive cell death
A single amino acid insertion in the WRKY domain of the Arabidopsis TIR-NBS-LRR-WRKY-type disease resistance protein SLH1 (sensitive to low humidity 1) causes activation of defense responses and hypersensitive cell death
复制标题
DOI：
10.1111/j.1365-313x.2005.02500.x
复制
发表时间：
2005-09-01
期刊：
影响因子：
7.2
通讯作者：
Shinozaki, K
中科院分区：
文献类型：
--
作者：
Noutoshi, Y;Ito, T;Shinozaki, K
在这项研究中，我们的特点是敏感的低湿度1（slh 1）突变体的拟南芥生态型No-0表现出正常的生长在琼脂平板培养基上，但在转移到土壤中显示生长停滞和发展的坏死病变。cDNA微阵列杂交和RNA凝胶印迹分析表明，与抗病性的激活相关的基因上调slh 1突变体在响应低湿度的条件。此外，slh 1突变体积累胼胝质，自发荧光化合物和水杨酸（SA）。我们证明SA是slh 1表型所需的，但不是PAD 4或NPR 1。SLH 1基因是通过图位克隆获得的，它编码一种抗性（R）样蛋白，由Toll和白细胞介素1受体同源结构域（TIR）、核苷酸结合结构域（NB）、富含亮氨酸重复序列（LRR）和羧基端WRKY结构域组成。SLH 1与拟南芥属生态型Nd-1的R基因RRS 1-R相同，该基因赋予对细菌病原体青枯雷尔氏菌GMI 1000的抗性，并且在No-0中也作为对该病原体的R基因起作用。我们确定了一个3 bp的插入突变slh 1的结果在WRKY结构域中添加一个氨基酸，从而削弱其DNA结合活性。我们的数据表明，SLH 1抗病信号可能是负调控其WRKY结构域的R蛋白和组成型防御激活赋予的slh 1突变的高湿度条件下抑制。
In this study we characterized the sensitive to low humidity 1 (slh1) mutant of Arabidopsis ecotype No-0 which exhibits normal growth on agar plate medium but which on transfer to soil shows growth arrest and development of necrotic lesions. cDNA microarray hybridization and RNA gel blot analysis revealed that genes associated with activation of disease resistance were upregulated in the slh1 mutants in response to conditions of low humidity. Furthermore, the slh1 mutants accumulate callose, autofluorescent compounds and salicylic acid (SA). We demonstrate that SA is required for the slh1 phenotype but not PAD4 or NPR1. SLH1 was isolated by map-based cloning and it encodes a resistance (R)-like protein consisting of a domain with Toll and interleukin-1 receptor homology (TIR), a nucleotide-binding domain (NB), leucine-rich repeats (LRR) and a carboxy-terminal WRKY domain. SLH1 is identical to the R gene RRS1-R of the Arabidopsis ecotype Nd-1, a gene which confers resistance to the bacterial pathogen Ralstonia solanacearum GMI1000 and also functions as an R gene to this pathogen in No-0. We identified a 3 bp insertion mutation in slh1 that results in the addition of a single amino acid in the WRKY domain; thereby impairing its DNA-binding activity. Our data suggest that SLH1 disease resistance signaling may be negatively regulated by its WRKY domain in the R protein and that the constitutive defense activation conferred by the slh1 mutation is inhibited by conditions of high humidity.