Zhang Junkang, Wang Lei, Zhao Han, Gong Longfeng, Xu Jichen
State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
Int J Biol Macromol. 2025 Jan;284(Pt 1):138077. doi: 10.1016/j.ijbiomac.2024.138077. Epub 2024 Nov 26.
WRKY transcription factors play key roles in plant responses to abiotic stress. In this study, we cloned and characterized the drought-induced WRKY gene SmWRKY12 from Salix matsudana Koidz. Following drought treatment, SmWRKY12 was significantly upregulated in the roots of the drought-tolerant willow variety 9901. Overexpressing SmWRKY12 in willow calli significantly increased drought tolerance. The results of yeast one-hybrid and dual-luciferase reporter assays showed that SmWRKY12 can bind to the promoter of the expansin gene SmEXPA13 and activate its expression. The results of yeast two-hybrid and split luciferase complementation assays showed that SmWRKY12 can interact with SmRAP2-7. The results of dual-luciferase and transgenic experiments showed that the combination of SmWRKY12 and SmRAP2-7 significantly increased the transcriptional regulation of SmWRKY12 on SmEXPA13. SmEXPA13 was introduced into willow calli and tobacco plants. Overexpressing SmEXPA13 significantly improved their performance under drought conditions. The results revealed a novel mechanism to tolerate drought stress through the SmWRKY12-SmRAP2-7-SmEXPA13 module in willow. This study also provided a new strategy for the molecular design and breeding of drought-tolerant plants.
WRKY转录因子在植物对非生物胁迫的响应中起关键作用。在本研究中，我们从旱柳中克隆并鉴定了干旱诱导的WRKY基因SmWRKY12。干旱处理后，耐旱柳树品种9901的根中SmWRKY12显著上调。在柳树愈伤组织中过表达SmWRKY12显著提高了耐旱性。酵母单杂交和双荧光素酶报告基因检测结果表明，SmWRKY12能与扩张蛋白基因SmEXPA13的启动子结合并激活其表达。酵母双杂交和分裂荧光素酶互补检测结果表明，SmWRKY12能与SmRAP2-7相互作用。双荧光素酶和转基因实验结果表明，SmWRKY12和SmRAP2-7的组合显著增强了SmWRKY12对SmEXPA13的转录调控。将SmEXPA13导入柳树愈伤组织和烟草植株中。过表达SmEXPA13显著改善了它们在干旱条件下的表现。结果揭示了柳树通过SmWRKY12-SmRAP2-7-SmEXPA13模块耐受干旱胁迫的新机制。本研究还为耐旱植物的分子设计和育种提供了新策略。
