Short Communication: Sonchus yellow net virus nucleocapsids form on nuclear rings enriched in phosphoprotein

Authors: MEULIA, TEA - The Ohio State University; Stewart, Lucy; GOODIN, MICHAEL - University Of Kentucky

Submitted to: Virus Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/7/2018
Publication Date: 10/15/2018
Citation: Meulia, T., Stewart, L.R., Goddin, M. 2018. Short Communication: Sonchus yellow net virus nucleocapsids form on nuclear rings enriched in phosphoprotein. Virus Research. 258:64-67. https://doi.org/10.1016/j.virusres.2018.10.005.
DOI: https://doi.org/10.1016/j.virusres.2018.10.005

Interpretive Summary: Sonchus yellow net virus (SYNV) is a plant-infecting rhabdovirus that shows unique cytopathlogies in the cells and nuclei of infected plants that are visible by electron microscopy and in fluorescent microscopy experiments. Various SYNV proteins have been studied to identify their subcellular localizations in infected cells and to understand how the virus proteins interact with each other and host plant proteins throughout the course of infection. Microscopy can elucidate the roles and cellular rearrangements induced by virus infection, and can clarify the events that occur within infected cells over the course of infection and the roles of virus-encoded proteins, but studies of SYNV infection over time were lacking. Here, we show electron micrograph studies of the ultrastructure of SYNV-infected cells. Ring structures caused by SYNV P protein are shown by electron microscopy and immunolabeling, confirming previous findings with fluorescent P protein but in the context of infection. Development of complex enveloped capsid structures and modification of plants cells and nuclei for virus replication and assembly of virions is also shown over time. Together, these data provide a framework for models of SYNV infection and P protein role at the cellular level for molecular plant virologists.

Technical Abstract: The phosphoprotein (P) of the nucleorhabdovirus Sonchus yellow net virus has been shown to form rings in virus-infected nuclei. Further examination by live-cell imaging, in combination with structural examination by transmission electron microscopy and immunolocalization demonstrated that P-rings do not from on nucleoli. Furthermore, viral nucleocapsids were shown to condense on the nucleoplasm-contacting surface of the rings. Such nucleocapsids appear to migrate singly to the nuclear envelope where they accumulate en masse in the perinuclear space.