State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China; State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, Harbin, 150040, China.
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China.
Plant Physiol Biochem. 2021 Jun;163:27-35. doi: 10.1016/j.plaphy.2021.03.042. Epub 2021 Mar 23.
NAC (NAM, ATAF1/2 and CUC2) transcription factors play critical roles in plant development and abiotic stress responses, and aquaporins have diverse functions in environmental stress responses. In this study, we described the salt-induced transcriptional responses of ThNAC12 and ThPIP2;5 in Tamarix hispida, and their regulatory mechanisms in response to salt stress. Using yeast one-hybrid (Y1H), chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays, we identified that ThNAC12 directly binds to the NAC recognition sequence (NACRS) of the ThPIP2;5 promoter and then activates the ThPIP2;5 expression. Subcellular localization and transcriptional activation assays demonstrated that ThNAC12 was a nuclear protein with a C-terminal transactivation domain. Compared with the corresponding control plants, transgenic plants overexpressing ThNAC12 exhibited enhanced salt tolerance and displayed increased reactive oxygen species (ROS) scavenging capability and antioxidant enzyme activity levels under salt stress. All results suggested that overexpression of ThNAC12 in plants enhanced salt tolerance through modulation of ROS scavenging via direct regulation of ThPIP2;5 expression in T. hispida.
NAC（NAM、ATAF1/2 和 CUC2）转录因子在植物发育和非生物胁迫响应中发挥着关键作用，而水通道蛋白在环境胁迫响应中具有多种功能。在这项研究中，我们描述了柽柳中的 ThNAC12 和 ThPIP2;5 的盐诱导转录反应，以及它们对盐胁迫的调节机制。通过酵母单杂交（Y1H）、染色质免疫沉淀（ChIP）和双荧光素酶报告基因 assays，我们鉴定出 ThNAC12 直接结合到 ThPIP2;5 启动子的 NAC 识别序列（NACRS）上，然后激活 ThPIP2;5 的表达。亚细胞定位和转录激活 assays 表明，ThNAC12 是一种具有 C 端转录激活结构域的核蛋白。与相应的对照植物相比，过表达 ThNAC12 的转基因植物在盐胁迫下表现出增强的耐盐性，并且显示出增强的活性氧（ROS）清除能力和抗氧化酶活性水平。所有结果表明，在柽柳中过表达 ThNAC12 通过直接调节 ThPIP2;5 的表达来增强植物的耐盐性，从而调节 ROS 的清除。
