Key Laboratory of Horticulture Science for Southern Mountains Regions of Ministry of Education, College of Horticulture and Landscape Architecture, Southwest University, Beibei, Chongqing 400715, China.
Academy of Agricultural Sciences of Southwest University, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Beibei, Chongqing 400715, China.
Int J Mol Sci. 2021 May 25;22(11):5593. doi: 10.3390/ijms22115593.
The WRKY gene family, which is one of the largest transcription factor (TF) families, plays an important role in numerous aspects of plant growth and development, especially in various stress responses. However, the functional roles of the WRKY gene family in loquat are relatively unknown. In this study, a novel WRKY gene, was characterized from which was significantly upregulated in leaves by melatonin treatment during drought stress. The protein, belonging to group II of the WRKY family, was localized in the nucleus. The results indicated that overexpression of increased cotyledon greening and root elongation in transgenic lines under abscisic acid (ABA) treatment. Meanwhile, overexpression of led to enhanced drought tolerance in transgenic lines, which was supported by the lower water loss, limited electrolyte leakage, and lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Further investigations showed that overexpression of promoted ABA-mediated stomatal closure and remarkably up-regulated ABA biosynthesis and stress-related gene expression in transgenic lines under drought stress. Overall, our findings reveal that EjWRKY17 possibly acts as a positive regulator in ABA-regulated drought tolerance.
WRKY 基因家族是最大的转录因子（TF）家族之一，在植物生长发育的众多方面发挥着重要作用，尤其是在各种胁迫响应中。然而，WRKY 基因家族在枇杷中的功能作用还相对未知。在这项研究中，从枇杷中鉴定出一个新的 WRKY 基因 ，该基因在干旱胁迫下褪黑素处理时在叶片中显著上调。该 蛋白属于 WRKY 家族的 II 组，定位于细胞核中。结果表明，在 ABA 处理下，过表达 增加了转基因 系的子叶变绿和根伸长。同时，过表达 导致转基因系耐旱性增强，这得到了更低的水分损失、有限的电解质泄漏以及更低水平的活性氧（ROS）和丙二醛（MDA）的支持。进一步的研究表明，过表达 促进了 ABA 介导的气孔关闭，并在干旱胁迫下显著上调了转基因系中 ABA 生物合成和应激相关基因的表达。总的来说，我们的研究结果表明 EjWRKY17 可能作为 ABA 调控耐旱性的正调控因子发挥作用。
