"Numerous plant viruses that seriously damage agricultural crops are transmitted by insects. However, the mechanisms enabling virus transmission by vector insects have been poorly understood, in part, due to the lack of useful tools. A persistent-propagative plant virus replicates and encodes nonstructural proteins to form various cytopathological structures in their two types of hosts: plants and vector insects. Here, we took advantage of unique biological tools, including insect vector cell culture and RNA interference (RNAi) induced by synthesized dsRNA, to investigate the molecular mechanisms facilitating the efficient spread of Rice dwarf virus (RDV), a persistent-propagative plant virus, among cells and organs of leafhopper vector. Our experimental evidence shows that RDV exploited virus-containing tubules composed of nonstructural viral protein Pns10 to traffic along actin-based cellular machinery, allowing efficient cell-to-cell spread of the virus in leafhopper vector. Consistently, and in support of a function of Pns10 tubules as a determinant for viral spread in vector insect, the introduction of dsRNA from Pns10 gene into cultured insect vector cells or intact insect strongly inhibited such tubule formation, preventing efficient viral intercellular spread in the leafhopper in vitro and in vivo and subsequent transmission by the vector, without significant effect on viral multiplication in leafhopper cells."
This paper has some of what HAVE to be some of the nicest confocal pics I have ever seen illustrating structures to do with viruses in cells - and explains an old mystery, which is - why do many plant-infecting viruses induce the formation of tubular structures? In this case, to spread the virus between cells of the vector. Nice!