Transformation of a continuous rat embryo fibroblast cell line requires three separate domains of simian virus 40 large T antigen. Journal   Journal of virology. Citation   J Virol. 66(5):2780-91 Publication date   1992 May Authors   Zhu J Rice PW Gorsch L Abate M Cole CN Investigators   Jiyue Zhu Grant agencies   National Cancer Institute Grants   NCI CA08835 NCI CA23018 NCI CA39259 MeSH headings   Antigens, Viral Cell Transformation, Viral Fibroblasts Simian virus 40 Tumor Virus Infections MeSH qualifiers   genetics pathology Abstract   Mouse C3H 10T1/2 cells and the established rat embryo fibroblast cell line REF-52 are two cell lines widely used in studies of viral transformation. Studies have shown that transformation of 10T1/2 cells requires only the amino-terminal 121 amino acids of simian virus 40 (SV40) large T antigen, while transformation of REF-52 cells requires considerably more of large T antigen, extending from near the N terminus to beyond residue 600. The ability of a large set of linker insertion, small deletion, and point mutants of SV40 T antigen to transform these two cell lines and to bind p105Rb was determined. Transformation of 10T1/2 cells was greatly reduced by mutations within the first exon of the gene for large T antigen but was only modestly affected by mutations affecting the p105Rb binding site or the p53 binding region. All mutants defective for transformation of 10T1/2 cells were also defective for transformation of REF-52 cells. In addition, mutants whose T antigens had alterations in the Rb binding site showed a substantial reduction in transformation of REF-52 cells, and the degree of this reduction could be correlated with the ability of the mutant T antigens to bind p105Rb. There was a tight correlation between the ability of mutants to transform REF-52 cells and the ability of their T antigens to bind p53. These results demonstrate that multiple regions of large T antigen are required for full transformation by SV40. Medline ID   92219362