The melon resistant gene cmv1 encodes a Vacuolar Protein Sorting 41, involved in intracellular trafficking to the vacuole. In the melon lines carrying cmv1 CMV strains of subgroup II are restricted to the bundle sheath cells and do not enter the phloem, whereas those of subgroup I overcome this restriction. The viral virulence factor that communicates with cmv1 is the Movement Protein (MP). We have studied the cellular localization of CmVPS41 from PS (susceptible) and SC (resistant) genotypes. They show significant differences in their localization pattern, with structures such as nuclear speckles, membrane dots and transvacuolar bridges that are numerous in CmVPS41PS, but in CmVPS41SC there are much fewer. These CmVPS41 characteristic structures co-localize with the late endosome. Moreover, CmVPS41 from exotic resistant melon accessions are similar to those of SC and the structure that most correlates with susceptibility is the presence of trans-vacuolar strands. Those patterns do not change in the presence of overexpressed MP. However, during a real infection those patterns change dramatically, with transvacuolar strands disappearing. This suggests that those structures are involved in susceptibility to CMV. We have also searched for interactors of CMV MP by Y2H and found one specific domain of a Niemann’s Peak protein C1 (NPC1), a protein that, in animals, is the receptor of Ebolavirus and other Flaviviruses. NPC1 is a transmembrane cholesterol transporter related to VPS41 and to local changes in membrane composition. CRISPR experiments are being carried out to impair both VPS41 and NPC1 in melon.

Esta reunión ha sido organizada gracias a la financiación recibida, con referencia: RED2018-102703-T. Esta ayuda corresponde a las acciones de dinamización «Redes de Investigación», del Programa Estatal de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I+D+I, Subprograma Estatal de Generación de Conocimiento, en el marco del Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020.

Resumen del trabajo presentado en la III Reunión de la Red Nacional de Virología de Plantas, RENAVIPLANT, celebrada en Murcia entre el 25 y el 27 de mayo de 2022.

Peer reviewed