Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
Sci Rep. 2019 Jan 24;9(1):724. doi: 10.1038/s41598-018-37035-2.
As the important source of natural fibers in the textile industry, cotton fiber quality and yield are often restricted to drought conditions because most of cotton plants in the world grow in the regions with water shortage. WRKY transcription factors regulate multiple plant physiological processes, including drought stress response. However, little is known of how the WRKY genes respond to drought stress in cotton. Our previous study revealed GhWRKY33 is leaf-specific and induced by drought stress. In this study, our data showed GhWRKY33 protein localizes to the cell nucleus and is able to bind to "W-box" cis-acting elements of the target promoters. Under drought stress, GhWRKY33 overexpressing transgenic Arabidopsis was withered much more quickly than wild type due to faster water loss. Moreover, GhWRKY33 transgenic plants displayed more tolerance to abscisic acid (ABA), relative to wild type. Expression of some drought stress-related genes and ABA-responsive genes were changed in the GhWRKY33 transgenic Arabidopsis with drought or ABA treatment. Collectively, our findings indicate that GhWRKY33 may act as a negative regulator to mediate plant response to drought stress and to participate in the ABA signaling pathway.
作为纺织工业中天然纤维的重要来源，棉花的纤维质量和产量经常受到干旱条件的限制，因为世界上大多数棉花植物生长在缺水的地区。WRKY 转录因子调节多种植物生理过程，包括干旱胁迫响应。然而，对于棉花中的 WRKY 基因如何响应干旱胁迫知之甚少。我们之前的研究表明 GhWRKY33 是叶特异性的，并受干旱胁迫诱导。在这项研究中，我们的数据表明 GhWRKY33 蛋白定位于细胞核，并能够与靶启动子的“W-box”顺式作用元件结合。在干旱胁迫下，由于失水更快，GhWRKY33 过表达的转基因拟南芥比野生型更快枯萎。此外，GhWRKY33 转基因植物对脱落酸（ABA）的耐受性相对野生型更强。在 GhWRKY33 转基因拟南芥中，一些与干旱胁迫相关基因和 ABA 响应基因的表达在干旱或 ABA 处理时发生了变化。总之，我们的研究结果表明，GhWRKY33 可能作为一个负调控因子，介导植物对干旱胁迫的响应，并参与 ABA 信号通路。
