Identification of simian virus 40 tumor and U antigens.

Abstract

The synthesis and identity of the tumor and U antigens of SV-40 were examined during productive infection in African green monkey kidney TC7 cells, abortive infection in mouse cells and in SV-40-transformed mouse [embryo 3T3] cells by using sodium dodecyl sulfate/polyacrylamide slab gel electrophoresis to analyze [35S]methionine-labeled radioimmune precipitates. The tumor and U antigenic sites are on the same 94,000, 89,000 and 84,000 MW species detected during productive infection; a 94,000 species is made during abortive infection; and a 94,000 species is found in transformed cells. The 94,000 species is relatively unstable compared to the relatively stable 89,000 and 84,000 species produced during productive infection. The stable 89,000 and 84,000 MW species are differentially extracted from productively infected cells, which suggests an intracellular compartmentation and/or different affinities of these species for cellular substrates. The 94,000 species synthesized during abortive infection is more stable than the comparable 94,000 species synthesized in transformed cells. Three tsA group mutants overproduce several unstable species of tumor antigen at restrictive temperature.