A RAF-SnRK2 kinase cascade mediates early osmotic stress signaling in higher plants

作者：Zhen Lin, Yuan Li, Zhengjing Zhang, Xiaolei Liu, Chuan‐Chih Hsu, Yanyan Du, Tian Sang, Chen Zhu, Yubei Wang, Viswanathan Satheesh, Pritu Pratibha, Yang Zhao, Chun‐Peng Song, W. Andy Tao, Jian‐Kang Zhu, Pengcheng Wang · 发表于：Nature Communications · 年份：2020 · DOI：10.1038/s41467-020-14477-9 · 被引用次数：291 · 研究领域：Plant Stress Responses and Tolerance、Plant responses to water stress、Plant Molecular Biology Research

Osmoregulation is important for plant growth, development and response to environmental changes. SNF1-related protein kinase 2s (SnRK2s) are quickly activated by osmotic stress and are central components in osmotic stress and abscisic acid (ABA) signaling pathways; however, the upstream components required for SnRK2 activation and early osmotic stress signaling are still unknown. Here, we report a critical role for B2, B3 and B4 subfamilies of Raf-like kinases (RAFs) in early osmotic stress as well as ABA signaling in Arabidopsis thaliana. B2, B3 and B4 RAFs are quickly activated by osmotic stress and are required for phosphorylation and activation of SnRK2s. Analyses of high-order mutants of RAFs reveal critical roles of the RAFs in osmotic stress tolerance and ABA responses as well as in growth and development. Our findings uncover a kinase cascade mediating osmoregulation in higher plants.