Journal Article

Salicylic acid-mediated plasmodesmal closure via Remorin-dependent lipid organization

Ma, Zhiming, Huang, Dingquan, Ke, Meiyu, Lam, Sin Man, Friml, Jiří, Yang, Liang, Chen, Xu, Ji, Changyang, Chen, Zichen, Chen, Chaofan, Tran, Tuan Minh, Han, Yanhong, Sun, Yanbiao, Cui, Yong, Shu, Guanghou, Jiang, Liwen, Miao, Yansong

2019

Overview

Plasmodesmata (PD) are plant-specific membrane-lined channels that create cytoplasmic and membrane continuities between adjacent cells, thereby facilitating cell–cell communication and virus movement. Plant cells have evolved diverse mechanisms to regulate PD plasticity in response to numerous environmental stimuli. In particular, during defense against plant pathogens, the defense hormone, salicylic acid (SA), plays a crucial role in the regulation of PD permeability in a callose-dependent manner. Here,we uncover a mechanism by which plants restrict the spreading of virus and PD cargoes using SA signaling by increasing lipid order and closure of PD. We showed that exogenous SA application triggered the compartmentalization of lipid raft nanodomains through a modulation of the lipid raft-regulatory protein, Remorin (REM). Genetic studies, superresolution imaging, and transmission electron microscopy observation together demonstrated that Arabidopsis REM1.2 and REM1.3 are crucial for plasma membrane nanodomain assembly to control PD aperture and functionality. In addition, we also found that a 14-3-3 epsilon protein modulates REM clustering and membrane nanodomain compartmentalization through its direct interaction with REM proteins. This study unveils a molecular mechanism by which the key plant defense hormone, SA, triggers membrane lipid nanodomain reorganization, thereby regulating PD closure to impede virus spreading.

• Publisher: National Academy of Sciences
• Subject: 14-3-3 protein / Apertures / Arabidopsis - metabolism / Arabidopsis Proteins - metabolism / Biological Sciences / Cell Communication - physiology / Cell interactions / Cell Membrane - metabolism / Clustering / Environmental effects / Glucans - metabolism / Lipids / Membrane Lipids - metabolism / Membrane Microdomains - metabolism / Membranes / Menopause / Permeability / Plant Biology / Plant cells / Plant Cells - metabolism / Plant Growth Regulators - metabolism / Plant Proteins - metabolism / Plant viruses / Plasmodesmata / Plasmodesmata - metabolism / Proteins / Salicylic acid / Salicylic Acid - metabolism / Signal Transduction - physiology / Spreading / Transmission electron microscopy / Viruses