Institute of Integrative Genome Biology, Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA.
Institute of Integrative Genome Biology, Department of Botany and Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA; FAFU-UCR Joint Center for Horticultural Biology and Metabolomics Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
Curr Biol. 2022 Feb 7;32(3):497-507.e4. doi: 10.1016/j.cub.2021.11.030. Epub 2021 Dec 6.
Sensing and signaling of cell wall status and dynamics regulate many processes in plants, such as cell growth and morphogenesis, but the underpinning mechanisms remain largely unknown. Here, we demonstrate that the CrRLK1L receptor kinase FERONIA (FER) binds the cell wall pectin, directly leading to the activation of the ROP6 guanosine triphosphatase (GTPase) signaling pathway that regulates the formation of the puzzle piece shape of pavement cells in Arabidopsis. The extracellular malectin domain of FER binds demethylesterified pectin in vivo and in vitro. Both loss-of-FER mutations and defects in pectin demethylesterification caused similar changes in pavement cell shape and ROP6 GTPase signaling. FER is required for the activation of ROP6 by demethylesterified pectin and physically and genetically interacts with the ROP6 activator, RopGEF14. Thus, our findings elucidate a signaling pathway that directly connects the cell wall pectin to cellular morphogenesis via the cell surface receptor FER.
细胞壁状态和动态的感应和信号转导调节植物中的许多过程，例如细胞生长和形态发生，但基础机制在很大程度上仍不清楚。在这里，我们证明了 CrRLK1L 受体激酶 FERONIA（FER）结合细胞壁果胶，直接导致调控拟南芥铺砖细胞拼图形状形成的 ROP6 鸟苷三磷酸酶（GTPase）信号通路的激活。FER 的细胞外甘露糖凝集素结构域在体内和体外结合去甲酯化的果胶。FER 的缺失突变和果胶去甲酯化缺陷都导致了铺砖细胞形状和 ROP6 GTPase 信号的相似变化。FER 对于去甲酯化果胶激活 ROP6 是必需的，并且在物理和遗传上与 ROP6 激活因子 RopGEF14 相互作用。因此，我们的研究结果阐明了一条信号通路，该通路通过细胞表面受体 FER 将细胞壁果胶直接连接到细胞形态发生。
