Arabidopsis DREB2C functions as a transcriptional activator of HsfA3 during the heat stress response
Arabidopsis DREB2C functions as a transcriptional activator of HsfA3 during the heat stress response
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DOI：
10.1016/j.bbrc.2010.09.038
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发表时间：
2010-10-15
影响因子：
3.1
通讯作者：
Lim, Chae Oh
中科院分区：
文献类型：
--
作者：
Chen, Huan;Hwang, Jung Eun;Lim, Chae Oh
脱水响应元件结合蛋白（DREB）家族在调节植物对非生物胁迫的反应中起重要作用。DREB2C是拟南芥2类dreb之一，由热胁迫（HS）诱导。在这里，我们提供了关于在HS信号转导级联中DREB2C与热休克因子A3 （HsfA3）相互作用的数据。RT-PCR结果显示，在过表达DREB2C的转基因植株中，21个拟南芥Hsfs中，HsfA3是上调最多的基因。DREB2C和HsfA3对HS的响应表现出相似的转录模式，DREB2C特异性地反激活了拟南芥叶肉原生质体中HsfA3依赖于re的转录。酵母单杂交实验和体外电泳迁移率转移实验进一步表明，DREB2C与位于HsfA3启动子中的两个DREs相互作用，并优先结合远端DRE2。DREB2C的缺失突变体表明，反激活活性位于c端区域。此外，双激活子-报告子实验表明，转基因植物中热休克蛋白（Hsp）基因的诱导可能归因于HsfA3的转录活性。综上所述，DREB2C和HsfA3是调控拟南芥耐热性的关键基因。(C) 2010爱思唯尔公司版权所有。
The dehydration-responsive element binding protein (DREB) family is important in regulating plant responses to abiotic stresses. DREB2C is one of the Arabidopsis class 2 DREBs and is induced by heat stress (HS). Here, we present data concerning the interaction of DREB2C with heat shock factor A3 (HsfA3) in the HS signal transduction cascade. RT-PCR showed that HsfA3 is the most up-regulated gene among the 21 Arabidopsis Hsfs in transgenic plants over-expressing DREB2C. DREB2C and HsfA3 displayed similar transcription patterns in response to HS and DREB2C specifically transactivated the DRE-dependent transcription of HsfA3 in Arabidopsis mesophyll protoplasts. Yeast one-hybrid assays and in vitro electrophoretic mobility shift assays further showed that DREB2C interacts with two DREs located in the HsfA3 promoter with a binding preference for the distal DRE2. Deletion mutants of DREB2C indicated that transactivation activity was located in the C-terminal region. In addition, dual activator-reporter assays showed that the induction of heat shock protein (Hsp) genes in transgenic plants could be attributed to the transcriptional activity of HsfA3. Taken together, these results indicate that DREB2C and HsfA3 are key players in regulating the heat tolerance of Arabidopsis. (C) 2010 Elsevier Inc. All rights reserved.