@article{mbs:/content/journal/jgv/10.1099/0022-1317-65-9-1449, author = "Fenwick, M. L. and McMenamin, Mary", title = "Synthesis of α (Immediate-Early) Proteins in Vero Cells Infected with Pseudorabies Virus", journal= "Journal of General Virology", year = "1984", volume = "65", number = "9", pages = "1449-1456", doi = "https://doi.org/10.1099/0022-1317-65-9-1449", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-65-9-1449", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", keywords = "pseudorabies virus", keywords = "IE proteins", keywords = "protein synthesis", abstract = "SUMMARY The synthesis of α (immediate-early) polypeptides in Vero cells infected with pseudorabies virus was studied. Cycloheximide was added at the beginning of infection and removed several hours later. The accumulated α mRNA was translated either in vivo in the presence of actinomycin D to prevent further mRNA synthesis, or in vitro. In intact cells three electrophoretically distinct virus-specific proteins were synthesized, with apparent molecular weights of approximately 180000 (A), 190000 (B) and 200000 (C). The accumulation of B and C was prevented by the proline analogue azetidine. Only protein A was detected in vitro. Proteins B and C were not detected in normally infected cells. All three were associated with the nuclear fraction of cell homogenates and A and B were phosphorylated. The radioactivity of B and C declined during a chase period while that of A increased. This change was prevented by adding cycloheximide during the chase. The pattern of chymotrypsin digestion products suggested that A and B at least were similar proteins. It is presumed that protein A is the single immediate-early protein previously described and analogous to ICP 4 of herpes simplex virus. The significance and function, if any, of proteins B and C is not known but it is possible that they represent stages in the formation or transport of A within the cell and that the progression depends on an unstable protein which is depleted in cells treated with cycloheximide.", }