A WRKY transcription factor, TaWRKY42-B, facilitates initiation of leaf senescence by promoting jasmonic acid biosynthesis

作者：Mingming Zhao, Xiaowen Zhang, Yongwei Liu, Ke Li, Qi Tan, Shuo Zhou, Geng Wang, Chunjiang Zhou · 发表于：BMC Plant Biology · 年份：2020 · DOI：10.1186/s12870-020-02650-7 · 被引用次数：47 · 研究领域：Plant Gene Expression Analysis、Postharvest Quality and Shelf Life Management、Plant Molecular Biology Research

BACKGROUND: Leaf senescence comprises numerous cooperative events, integrates environmental signals with age-dependent developmental cues, and coordinates the multifaceted deterioration and source-to-sink allocation of nutrients. In crops, leaf senescence has long been regarded as an essential developmental stage for productivity and quality, whereas functional characterization of candidate genes involved in the regulation of leaf senescence has, thus far, been limited in wheat. RESULTS: In this study, we analyzed the expression profiles of 97 WRKY transcription factors (TFs) throughout the progression of leaf senescence in wheat and subsequently isolated a potential regulator of leaf senescence, TaWRKY42-B, for further functional investigation. By phenotypic and physiological analyses in TaWRKY42-B-overexpressing Arabidopsis plants and TaWRKY42-B-silenced wheat plants, we confirmed the positive role of TaWRKY42-B in the initiation of developmental and dark-induced leaf senescence. Furthermore, our results revealed that TaWRKY42-B promotes leaf senescence mainly by interacting with a JA biosynthesis gene, AtLOX3, and its ortholog, TaLOX3, which consequently contributes to the accumulation of JA content. In the present study, we also demonstrated that TaWRKY42-B was functionally conserved with AtWRKY53 in the initiation of age-dependent leaf senescence. CONCLUSION: Our results revealed a novel positive regulator of leaf senescence, TaWRKY42-B, which mediates JA-related leaf se...