Protein kinase C stimulation increases the transforming ability of the polyoma virus middle T antigen.
Exposure of dexamethasone-treated cells of the mT-1 line of F111 rat cells bearing a dexamethasone-inducible polyoma virus middle T (mT) antigen gene to very low concentrations of the protein kinase C-stimulating phorbol ester TPA increased the association of mT antigen with the cellular pp60c-src tyrosine protein kinase, as indicated by an increased phosphorylation of tyrosine residues of mT in mT:pp60c-src complexes precipitated from extracts of the TPA-treated cells by anti-mT antibodies. This TPA (hence probably protein kinase C)-enhanced association of mT with pp60c-src was accompanied by a large increase in the transforming ability of mT as indicated by a much enhanced ability of TPA-treated mT-1 cells producing submaximal levels of mT to proliferate while suspended in semi-solid medium and to form foci on confluent monolayers of normal F111 cells. NRCC NO: 26558.
D000952:Antigens, Polyomavirus Transforming; D000957:Antigens, Viral, Tumor / Q000378:metabolism*; D002460:Cell Line; D002472:Cell Transformation, Viral; D004789:Enzyme Activation / Q000187:drug effects; D009856:Oncogene Proteins, Viral / Q000378:metabolism*; D011120:Polyomavirus / Q000276:immunology*; D011493:Protein Kinase C / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D016392:Proto-Oncogene Proteins pp60(c-src); D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000952:Antigens, Polyomavirus Transforming; D000957:Antigens, Viral, Tumor; D009856:Oncogene Proteins, Viral; D011518:Proto-Oncogene Proteins; D016392:Proto-Oncogene Proteins pp60(c-src); D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate