1. CsbZIP50 binds to the G-box/ABRE motif in CsRD29A promoter to enhance drought tolerance in cucumber.
- Author
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Li, Yafei, Xian, Xuan, Guo, Luqin, Zhang, Jialong, Gan, Chaolin, Wang, Zhirong, Li, Hongfei, Li, Xingsheng, Yuan, Xiaowei, Zhang, Na, and Guo, Yang-Dong
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CUCUMBERS , *DROUGHT tolerance , *LEUCINE zippers , *REACTIVE oxygen species , *ABSCISIC acid , *TRANSCRIPTION factors , *GENE expression - Abstract
Cucumber (Cucumis sativus L.) is a high water-demanding and drought-susceptible vegetable crop. Basic leucine zipper (bZIP) transcription factors (TFs) have been linked to drought stress response in plants. Here we characterized a G subfamily gene in cucumber, CsbZIP50 , which was strongly induced by drought stress and an exogenous abscisic acid (ABA) treatment. Under drought stress, CsbZIP50 -overexpressing plants exhibited enhanced drought tolerance compared with wild-type plants, as indicated by the higher antioxidant enzyme activities but lower reactive oxygen species (ROS) and malondialdehyde contents. In addition, overexpression of CsbZIP50 enhanced cucumber's sensitivity to exogenously applied ABA, and up-regulated the expression of its stress-related genes. Moreover, we found that CsbZIP50 activated CsRD29 expression by directly binding to the G-box/ABRE cis-acting element in its promoter, both in vitro and in vivo. Yeast two-hybrid, luciferase complementation imaging, and pull-down assays showed that CsbZIP50 physically interacted with two IQ domain-containing proteins, CsIQD1 and CsIQD4, both of which promoted the ability of CsbZIP50 to activate the expression of CsRD29. Taken together, our results show that CsbZIP50 enhances drought stress tolerance in cucumber by regulating drought-responsive gene expression and ROS levels. • CsbZIP50 is a G subfamily of the bZIP TF, which was induced by drought stress and exogenous ABA treatment. • Expression of CsbZIP50 positively regulates drought tolerance by improving stomata closure and ROS scavenging. • CsbZIP50 targeted CsRD29A and the expression activation effect was enhanced by interacting with CsIQD1 and CsIQD4. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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