Characterization of NAC transcription factor NtNAC028 as a regulator of leaf senescence and stress responses

作者：Lichao Wen, Tao Liu, Zhichao Deng, Zenglin Zhang, Qi Wang, Weifeng Wang, Wei Li, Yongfeng Guo · 发表于：Frontiers in Plant Science · 年份：2022 · DOI：10.3389/fpls.2022.941026 · 被引用次数：22 · 研究领域：Plant Stress Responses and Tolerance、Plant Gene Expression Analysis、Photosynthetic Processes and Mechanisms

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 NtNAC028 during leaf yellowing. In this study, we found that NtNAC028 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. NtNAC028 loss-of-function tobacco plants generated via CRISPR-Cas9 showed delayed leaf senescence and increased tolerance to drought and salt stresses. Meanwhile NtNAC028 overexpression led to precocious leaf senescence and hypersensitivity to abiotic stresses in Arabidopsis , indicating that NtNAC028 functions as a positive regulator of natural leaf senescence and a negative regulator of stress tolerance. Furthermore, NtNAC028 -overexpressing Arabidopsis plants showed lower antioxidant enzyme activities, higher reactive oxygen species (ROS), and H 2 O 2 accumulation under high salinity, resulted in more severe oxidative damage after salt stress treatments. On the other hand, NtNAC028 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 NtNAC028 might act as a vital regulator for plant stress response likely by mediating ROS scavenging ability. Col...