|Redinbaugh, Margaret - Peg|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 6/12/2008
Publication Date: 6/28/2008
Citation: Fiorella, C., Chi-Wei, T., Redinbaugh, M.G., Hogenhout, S. 2008. Nuclear import of Maize fine streak virus proteins in Drosophila S2 cells. Phytopathology. 98:539.
Technical Abstract: Maize fine streak virus (MFSV) is a member of the genus Nucleorhabdovirus, family Rhabdoviridae and is transmitted by the leafhopper Graminella nigrifons. The virus replicates in both its plant host and in its insect vector. Nucleorhabdoviruses replicate in the nucleus and assemble at the inner nuclear membrane of their plant and insect hosts, so the nuclear import of viral proteins is critical to complete viral morphogenesis. Nuclear import of proteins is mediated by a highly conserved machinery in eukaryotes that depend on Importin alpha and beta. These two components are the key to the recognition and transport of proteins carrying nuclear localization signals. The molecular mechanisms involved in nuclear import of rhabdoviral proteins remain unclear. We used in situ assays to demonstrate the role for importin alpha in nuclear import of viral proteins. Fluorescent-protein fusions of the MFSV N and P proteins were transfected into Drosophila S2 cells in which the synthesis of importin alpha was knocked down by RNA interference. In importin alpha-depleted cells the MFSV N protein was distributed throughout the cells, whereas the MFSV N protein was found only in nuclei of control cells. When MFSV N and P genes were co-expressed in importin alpha-depleted cells, both N and P proteins were found throughout cells in contrast to the nuclear localization observed in control cells. These results indicated that importin alpha is involved in nuclear import of MFSV N protein and N and P protein complex into insect cells.