Arabidopsis Di19 Functions as a Transcription Factor and Modulates PR1, PR2, and PR5 Expression in Response to Drought Stress
Arabidopsis Di19 Functions as a Transcription Factor and Modulates PR1, PR2, and PR5 Expression in Response to Drought Stress
复制标题
DOI：
10.1093/mp/sst031
复制
发表时间：
2013-09-01
期刊：
影响因子：
27.5
通讯作者：
Chen, Yi-Fang
中科院分区：
文献类型：
--
作者：
Liu, Wen-Xin;Zhang, Fei-Cui;Chen, Yi-Fang
拟南芥Di 19编码Cys 2/His 2型锌指蛋白，是一种新型的转录因子。Di 19通过上调PR 1、PR 2和PR 5基因的表达参与拟南芥对干旱胁迫的应答，拟南芥Di 19（Drought-induced）基因家族编码7个Cys 2/His 2型锌指蛋白，其中大部分功能未知。在这里，我们报告说，Di 19作为一个转录调节因子，并参与拟南芥响应干旱胁迫通过上调病程相关的PR 1，PR 2和PR 5基因的表达。Di 19 T-DNA插入突变体di 19对干旱胁迫更敏感，而Di 19过表达株系比野生型植株更耐受干旱胁迫。Di 19在我们的酵母试验中表现出反式激活活性，并且其反式激活活性在体内得到进一步证实。DNA结合分析显示Di 19可以与TACA（A/G）T元件结合，染色质免疫沉淀（ChIP）分析表明Di 19可以与PR 1、PR 2和PR 5启动子内的TACA（A/G）T元件结合。qRTPCR结果显示，Di 19促进了PR 1、PR 2和PR 5的表达，而CPK 11在细胞核中与Di 19相互作用后，促进了PR 1、PR 2和PR 5的表达。与Di 19-过表达系类似，PR 1-、PR 2-和PR 5-过表达系也表现出耐旱表型。水杨酸类似物INA预处理可提高植物的耐旱性。综上所述，这些数据表明，Di 19，一种新型的转录因子，直接上调表达的PR 1，PR 2和PR 5响应干旱胁迫，其反式激活活性增强CPK 11。
Arabidopsis Di19 encodes a Cys2/His2-type zinc-finger protein and functions as a new type of transcription factor. Di19 is involved in Arabidopsis responses to drought stress through up-regulation of PR1, PR2, and PR5 gene expression.The Arabidopsis Di19 (Drought-induced) gene family encodes seven Cys2/His2-type zinc-finger proteins, most with unknown functions. Here, we report that Di19 functioned as a transcriptional regulator and was involved in Arabidopsis responses to drought stress through up-regulation of pathogenesis-related PR1, PR2, and PR5 gene expressions. The Di19 T-DNA insertion mutant di19 was much more sensitive to drought stress, whereas the Di19-overexpressing lines were much more tolerant to drought stress compared with wild-type plants. Di19 exhibited transactivation activity in our yeast assay, and its transactivation activity was further confirmed in vivo. DNA-binding analysis revealed that Di19 could bind to the TACA(A/G)T element and chromatin immunoprecipitation (ChIP) assays demonstrated that Di19 could bind to the TACA(A/G)T element within the PR1, PR2, and PR5 promoters. qRTPCR results showed that Di19 promoted the expressions of PR1, PR2, and PR5, and these heightened expressions were enhanced by CPK11, which interacted with Di19 in the nucleus. Similarly to the Di19-overexpressing line, PR1-, PR2-, and PR5-overexpressing lines also showed the drought-tolerant phenotype. The pre-treatment with salicylic acid analogs INA can enhance plants drought tolerance. Taken together, these data demonstrate that Di19, a new type of transcription factor, directly up-regulates the expressions of PR1, PR2, and PR5 in response to drought stress, and its transactivation activity is enhanced by CPK11.