449 / 2019-02-18 09:30:39

Salicylic Acid-mediated Plasmodesmata Closure by Remorin-dependent Lipid organization

plasmodesmata, lipid raft, virus movement, Remorin genes

全体主题 > Cell Biology

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. Nevertheless, the underlying mechanism is largely elusive. Here, we uncover a novel mechanism by which plants restrict virus spreading through a SA-mediated membrane lipid raft organization and PD permeability. We showed that exogenous SA application regulates the compartmentalization of lipid raft nanodomains through a modulation of the lipid raft-regulatory protein, Remorin (REM). Genetic studies, transcriptome analysis and transmission electron microscopy observations 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 therefore membrane nanodomain compartmentalization through its direct interaction with REM protein. This study unveils a novel molecular mechanism by which the key plant defense hormone, SA triggers plasma membrane lipid raft reorganization, thereby regulating PD closure to limit virus spreading.