AUTHOR=Kan Chengcheng , Zhang Yi , Wang Hou-Ling , Shen Yingbai , Xia Xinli , Guo Hongwei , Li Zhonghai 

TITLE=Transcription Factor NAC075 Delays Leaf Senescence by Deterring Reactive Oxygen Species Accumulation in Arabidopsis

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.634040

DOI=10.3389/fpls.2021.634040

ISSN=1664-462X

ABSTRACT=<p>Leaf senescence is a highly complex genetic process that is finely tuned by multiple layers of regulation. Among them, transcriptional regulation plays a critical role in controlling the initiation and progression of leaf senescence. Here, we found that the NAC transcription factor NAC075 functions as a novel negative regulator of leaf senescence. Loss of function of NAC075 promotes leaf senescence in an age-dependent manner, whereas constitutive overexpression of <italic>NAC075</italic> delays senescence in <italic>Arabidopsis</italic>. Transcriptome analysis revealed that transcript levels of antioxidant enzymes such as catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) are significantly suppressed in <italic>nac075</italic> mutants compared with wild-type plants. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) analyses revealed that NAC075 directly binds the promoter of <italic>catalase 2</italic> (<italic>CAT2</italic>). Moreover, genetic analysis showed that overexpression of <italic>CAT2</italic> suppresses the overproduction of reactive oxygen species (ROS) and the early senescence phenotypes of <italic>nac075</italic> mutants, suggesting that CAT2 acts downstream of NAC075 to delay leaf senescence by repressing ROS accumulation. Collectively, our findings provide a new regulatory module involving NAC075-CAT2-ROS in controlling leaf senescence in <italic>Arabidopsis</italic>.</p>