Viral Manipulation of Plant Host Membranes

Plant viruses, like animal viruses, induce the formation of novel intracellular membranous structures that provide an optimum environment for coordinating diverse viral processes such as viral RNA synthesis and virus egress. Membrane reshaping is accomplished by the expression of specific membrane- associated viral proteins that interact with host proteins involved in membrane trafficking processes. Plant virus- induced membranous structures are motile, and this intracellular motility is required for the transport of viral RNA from sites of synthesis to plasmodesmata, which are used to move viral RNA from cell to cell. Cellular movement of these virus- induced bodies requires myosin motor activity and is dependent on the secretory pathway. The coupling of membrane- associated replication complexes with virus intra- and intercellular trafficking may explain why viral infection of neighboring cells is established rapidly and efficiently.