The Fuction Of Endoplasmic Reticulum In The Movement Of Spotted Wilt Tospovirus

Plant viruses need to move within and between cells to establish infection.To accomplish this task,Plant viruses not only utilize viral-encoded MPs or other viral components for viral intra-and intercellular movement,but also co-opt different host cell transport machineries for their movement,in the study,We used Tomato spotted wilt tospovirus(TSWV),the type member of Tospovirus as a model to understand the involvement of host cell transport systems ER for intercellular movement of the NSm MP and TSWV,which is important to understand the contribution of host cell transport systems to the intercellular movement of multipartite negative-strand RNA plant viruses including tospoviruses.In the study,we find an RHD3 mutant that is defectivein the generation of the tubular ER network.This mutant with nonbranched ER gives a clean background and consistent outcome and provides us a powerful genetic system to investigatethe contribution of the ER membrane network to the intercellular movement of TSWV.By using this system,we were able to identify that virus infection was strongly delayed in the rhd3 mutant.The protoplast assay further revealed that the reduced viral infection was not due to defective replication.Thus,we established that the ER membrane transport system is important for TSWV to establish infection of the plant.As many MPs of other plant virus,NSm also can induce the formation of surface tubules in Arabidopsis thaliana leaf mesophyll protoplasts,we find that ER may participate the formation of the tubules.however,the formation of tubules has no significant differences between the rhd3 mutant,and WT.Thus,Tospovirus NSm may represent a new subcategory of movement protein with a distinct membrane association property in 30K superfamly.