Host cell protein kinases in nonsegmented negative-strand virus (mononegavirales) infection.
Phosphorylation of one or more viral proteins is probably an essential step in the life cycle of every member of the nonsegmented negative-strand RNA virus (mononegavirales [MNV]) group. Since no virally encoded protein kinases have been discovered in this group, phosphorylation is effected entirely by host cell kinases. The virally encoded P proteins of the MNV are the only ones consistently phosphorylated with a stoichiometry > or =1. The P protein of vesicular stomatitis virus (VSV), and perhaps also of respiratory syncytial virus, are the only ones for which a function of phosphorylation has been established. Phosphorylation by casein kinase 2 at one or more identified sites in the VSV P protein activates transcriptional activity by promoting formation of a homotrimer, which is then capable of binding the RNA polymerase and attaching it to the N protein-RNA template. A second phosphorylation of VSV P protein by a different kinase also occurs, dependent upon prior modification by casein kinase 2, but its function is not definitely known. Phosphorylation of the other MNV P proteins may serve a different purpose. No evidence has been obtained yet for any function for phosphorylation of any other MNV protein.
Lenard
J
J
Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA. lenard@umdnj.edu
D047388:Casein Kinases; D006801:Humans; D018096:Mononegavirales / Q000201:enzymology / Q000378:metabolism; D018701:Mononegavirales Infections / Q000201:enzymology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism / Q000502:physiology*; D014158:Transcription, Genetic; D014721:Vesicular stomatitis Indiana virus / Q000201:enzymology / Q000378:metabolism
D011494:Protein Kinases; D047388:Casein Kinases