National Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, Jiangsu Province, China.
Guangdong Key Laboratory of Tea Plant Resources Innovation & Utilization, Tea Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, 510640, Guangdong Province, China.
Plant Mol Biol. 2022 Aug;109(6):741-759. doi: 10.1007/s11103-022-01272-x. Epub 2022 May 12.
WRKY transcription factors play important roles in abiotic stress by directly regulating stress-related genes. However, the molecular mechanism of its involvement in salt stress in pak-choi is still poorly understood. In this study, we elucidated the function of BcWRKY1 from pak-choi (Brassica rapa ssp. chinensis) in salt stress. The expression level of BcWRKY1 showed the highest in rosette leaves among different tissues and was induced by salt and ABA treatment in pak-choi. Subcellular localization showed that BcWRKY1 was located in nucleus. The transgenic Arabidopsis overexpressing BcWRKY1 exhibited enhanced salt sensitivity and higher HO contents, which were further confirmed by silencing BcWRKY1 in pak-choi. In addition, the expression of ZAT12 was negatively regulated with BcWRKY1 under salt stress both in pak-choi and Arabidopsis. Yeast one-hybrid and dual luciferase reporter assay showed that BcWRKY1 could bind to the promoter of BcZAT12, and BcsAPX expression was activated by BcZAT12. To sum up, we propose a BcWRKY1-BcZAT12-BcsAPX regulatory model that involves in pak-choi salt stress response.
WRKY 转录因子通过直接调控与胁迫相关的基因在非生物胁迫中发挥重要作用。然而，其在白菜中参与盐胁迫的分子机制仍知之甚少。在本研究中，我们阐明了来自白菜（ Brassica rapa ssp. chinensis ）的 BcWRKY1 在盐胁迫中的功能。BcWRKY1 的表达水平在不同组织的莲座叶中最高，并受到盐和 ABA 处理的诱导。亚细胞定位表明 BcWRKY1 位于细胞核内。过表达 BcWRKY1 的转基因拟南芥表现出增强的盐敏感性和更高的 HO 含量，这在白菜中沉默 BcWRKY1 后得到了进一步证实。此外，在盐胁迫下，BcWRKY1 在白菜和拟南芥中均负调控 ZAT12 的表达。酵母单杂交和双荧光素酶报告基因检测表明，BcWRKY1 可以结合 BcZAT12 的启动子，并且 BcsAPX 的表达被 BcZAT12 激活。总之，我们提出了一个涉及白菜盐胁迫反应的 BcWRKY1-BcZAT12-BcsAPX 调控模型。
