Wen Lichao, Liu Tao, Deng Zhichao, Zhang Zenglin, Wang Qi, Wang Weifeng, Li Wei, Guo Yongfeng
Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, Shandong, China.
Front Plant Sci. 2022 Aug 15;13:941026. doi: 10.3389/fpls.2022.941026. eCollection 2022.
NAC proteins constitute one of the largest transcription factor families and are involved in regulation of plant development and stress responses. Our previous transcriptome analyses of tobacco revealed a significant increase in the expression of during leaf yellowing. In this study, we found that was rapidly upregulated in response to high salinity, dehydration, and abscisic acid (ABA) stresses, suggesting a vital role of this gene in abiotic stress response. loss-of-function tobacco plants generated CRISPR-Cas9 showed delayed leaf senescence and increased tolerance to drought and salt stresses. Meanwhile overexpression led to precocious leaf senescence and hypersensitivity to abiotic stresses in , indicating that functions as a positive regulator of natural leaf senescence and a negative regulator of stress tolerance. Furthermore, -overexpressing plants showed lower antioxidant enzyme activities, higher reactive oxygen species (ROS), and HO accumulation under high salinity, resulted in more severe oxidative damage after salt stress treatments. On the other hand, mutation in tobacco resulted in upregulated expression of ROS-scavenging and abiotic stress-related genes, higher antioxidant enzyme activities, and enhanced tolerance against abiotic stresses, suggesting that might act as a vital regulator for plant stress response likely by mediating ROS scavenging ability. Collectively, our results indicated that the plays a key regulatory role in leaf senescence and response to multiple abiotic stresses.
NAC蛋白构成了最大的转录因子家族之一，并参与植物发育和胁迫响应的调控。我们之前对烟草的转录组分析显示，在叶片变黄过程中，[具体基因名称缺失]的表达显著增加。在本研究中，我们发现[具体基因名称缺失]在高盐、脱水和脱落酸（ABA）胁迫下迅速上调，表明该基因在非生物胁迫响应中起着至关重要的作用。利用CRISPR-Cas9技术构建的[具体基因名称缺失]功能丧失型烟草植株表现出叶片衰老延迟以及对干旱和盐胁迫的耐受性增加。同时，[具体基因名称缺失]过表达导致[具体植物名称缺失]叶片早衰以及对非生物胁迫超敏，表明[具体基因名称缺失]作为自然叶片衰老的正调控因子和胁迫耐受性的负调控因子发挥作用。此外，[具体植物名称缺失]过表达植株在高盐条件下表现出较低的抗氧化酶活性、较高的活性氧（ROS）和HO积累，在盐胁迫处理后导致更严重的氧化损伤。另一方面，烟草中[具体基因名称缺失]突变导致ROS清除和非生物胁迫相关基因的表达上调、抗氧化酶活性更高以及对非生物胁迫的耐受性增强，表明[具体基因名称缺失]可能通过介导ROS清除能力而成为植物胁迫响应的重要调控因子。总体而言，我们的结果表明[具体基因名称缺失]在叶片衰老和对多种非生物胁迫的响应中起关键调控作用。
