Melatonin activates the OsbZIP79–OsABI5 module that orchestrates nitrogen and ROS homeostasis to alleviate nitrogen-limitation stress in rice

作者：Meng Jiang, Yue Song, Ruifang Yang, Chenfan Zheng, Yunchao Zheng, Huali Zhang, Shan Li, Yuanyuan Tan, Jianzhong Huang, Qingyao Shu, Ruiqing Li · 发表于：Plant Communications · 年份：2023 · DOI：10.1016/j.xplc.2023.100674 · 被引用次数：29 · 研究领域：Plant nutrient uptake and metabolism、Plant Molecular Biology Research、Plant Stress Responses and Tolerance

Melatonin (Mel) has previously been reported to effectively alleviate nitrogen-limitation (N-L) stress and thus increase nitrogen-use efficiency (NUE) in several plants, but the underlying mechanism remains obscure. Here, we revealed that OsbZIP79 (BASIC LEUCINE ZIPPER 79) is transcriptionally activated under N-L conditions, and its expression is further enhanced by exogenous Mel. By the combined use of omics, genetics, and biological techniques, we revealed that the OsbZIP79-OsABI5 (ABSCISIC ACID INSENSITIVE 5) module stimulated regulation of reactive oxygen species (ROS) homeostasis and the uptake and metabolism of nitrogen under conditions of indoor nitrogen limitation (1/16 normal level). OsbZIP79 activated the transcription of OsABI5, and OsABI5 then bound to the promoters of target genes, including genes involved in ROS homeostasis and nitrogen metabolism, activating their transcription. This module was also indispensable for upregulation of several other genes involved in abscisic acid catabolism, nitrogen uptake, and assimilation under N-L and Mel treatment, although these genes were not directly transactivated by OsABI5. Field experiments demonstrated that Mel significantly improved rice growth under low nitrogen (L-N, half the normal level) by the same mechanism revealed in the nitrogen-limitation study. Mel application produced a 28.6% yield increase under L-N and thus similar increases in NUE. Also, two OsbZIP79-overexpression lines grown in L-N field plots had si...