Role of the foamy virus Pol cleavage site in viral replication.
Foamy virus Pol precursor protein processing by the viral protease occurs at only one site, releasing a protease-reverse transcriptase and an integrase protein. To examine whether the cleavage of the Pol precursor protein is necessary for enzymatic activities and efficient viral replication, several mutations were generated around the cleavage site. All cleavage site mutants synthesize wild-type levels of Pol precursor protein. Mutants containing more than two amino acid substitutions around the cleavage site exhibit no detectable Pol processing. The Pol cleavage site is not required for the production of infectious particles in a single round of infection, but is important for subsequent rounds of viral infection. Mutations around the cleavage site affected the enzymatic activities of the protease and reverse transcriptase and prevented replication after two rounds of infection. Interestingly, Pol encapsidation is significantly reduced in some of the mutants.
Roy
Jacqueline
J
Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Seattle, WA 98109-1024, USA.
Linial
Maxine L
ML
D019943:Amino Acid Substitution; D015684:Gene Products, pol / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016296:Mutagenesis; D009154:Mutation; D010447:Peptide Hydrolases / Q000378:metabolism; D011498:Protein Precursors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D018741:Replication Origin; D016092:Spumavirus / Q000235:genetics / Q000502:physiology*; D014779:Virus Replication
D015684:Gene Products, pol; D011498:Protein Precursors; D012194:RNA-Directed DNA Polymerase; D010447:Peptide Hydrolases