Replication of simian virus 40 in permissive cells: assembly of virus components.

Abstract

SUMMARY Incubation in medium lacking arginine of monkey kidney cells infected with simian virus 40 resulted in a marked inhibition of production of both infectious virus and empty capsids. Virus DNA synthesis and formation of a virus DNA-protein complex were unaffected. All the virus structural polypeptides were made, although in reduced amounts (42%) when compared with infected cells incubated in medium containing arginine. Protein synthesis was inhibited in uninfected cells deprived of arginine. All the newly synthesized virus proteins were found in the nuclei of arginine-deprived cells. Addition of arginine to arginine-deprived cells resulted in the assembly of pre-synthesized virus components into infectious virus and empty capsids, as well as the production of virus from virus proteins and DNA synthesized after the addition of arginine. Studies with inhibitors of protein and DNA synthesis suggested that two late virus functions were affected in the absence of arginine: the assembly of capsids and the encapsidation of DNA by capsids to form infectious virus.