Rice dwarf virus is engulfed into and released via vesicular compartments in cultured insect vector cells

National Agricultural Research Center, 3-1-1 Kannondai, Tsukuba, Ibaraki 305-8666, Japan.
Journal of General Virology (Impact Factor: 3.18). 12/2008; 89(Pt 11):2915-20. DOI: 10.1099/vir.0.2008/002063-0
Source: PubMed


Vector insect cells infected with Rice dwarf virus had vesicular compartments containing viral particles located adjacent to the viroplasm when examined by transmission electron and confocal microscopy. Such compartments were often at the periphery of infected cells. Inhibitors of vesicular transport, brefeldin A and monensin, and an inhibitor of myosin motor activity, butanedione monoxime, abolished the formation of such vesicles and prevented the release of viral particles from infected cells without significant effects on virus multiplication. Furthermore, the actin-depolymerizing drug, cytochalasin D, inhibited the formation of actin filaments without significantly interfering with formation of vesicular compartments and the release of viruses from treated cells. These results together revealed intracellular vesicular compartments as a mode for viral transport in and release from insect vector cells infected with a plant-infecting reovirus.

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    • "In the case of RDV, multiple pathways have been reported for viral egress from infected insect cells without cell lysis. One of the virus-release pathways involves secretory exosomes derived from multi-vesicular bodies (MVBs; Wei et al., 2008b, 2009a). Virus-containing MVBs are frequently observed in the peripheral region of the viroplasms as well as near the cytoplasmic membrane. "
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    • "455 However, it is now well described that many viruses are able to " hijack " cellular secretion pathways and particularly the endosomal multivesicular bodies (MVBs) and the cell membrane lipid rafts. As a consequence, these serve as concentration platforms or delivery vehicles for viral structural elements, facilitating assembly and release of infectious virions (Gould et al., 2003; Wei et al., 2008; Hurley and Hanson, 2010; de 460 Gassart et al., 2009; Izquierdo-Useros et al., 2010; Ono, 2010). Parasitoid VLPs, PDVs or viruses may then act similarly to perform assembly or budding (Thaa et al., 2010) as a "cheap" way to exit the cell, by using components that mediate endosomal sorting. "
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    • "N. Miyazaki and others that are exploited by authentic RDV particles for their transport and release from infected insect-host cells (Wei et al., 2008, 2009a). Our results suggest that assembled VLPs, generated in non-host Sf9 cells, are released from these cells via vesicular compartment-like structures in a manner similar to that of intact viral particles (Wei et al., 2008). "
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