Stoichiometry of cellular and viral components in the polyomavirus middle-T antigen-tyrosine kinase complex.
Our results indicate that only one type of tyrosine kinase is present within each middle-T antigen-tyrosine kinase complex, suggesting that middle-T antigen forms separate complexes with different tyrosine kinases. Furthermore, we determined that there is only one molecule of middle-T antigen within any one of these complexes. We interpret this to mean that in any given cell, polyomavirus transformation involves, at least in part, the simultaneous deregulation of a number of separate pathways controlling cellular proliferation. Finally, we also demonstrate that the separate middle-T:pp60c-src and middle-T:pp59c-fyn complexes are each able to interact with the same cellular p81/85-kDa phosphoprotein, a possible component of the phosphatidylinositol kinase.
Cheng
S H
SH
Laboratory of Cellular Regulation, Genzyme Corporation, Framingham, Massachusetts 01701.
Espino
P C
PC
Marshall
J
J
Harvey
R
R
Smith
A E
AE
D019870:1-Phosphatidylinositol 4-Kinase; D000818:Animals; D000957:Antigens, Viral, Tumor / Q000378:metabolism*; D046911:Macromolecular Substances; D051379:Mice; D008970:Molecular Weight; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism; D011233:Precipitin Tests; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051076:Proto-Oncogene Proteins c-fyn; D016392:Proto-Oncogene Proteins pp60(c-src)
D000957:Antigens, Viral, Tumor; D046911:Macromolecular Substances; D011518:Proto-Oncogene Proteins; D010770:Phosphotransferases; D019870:1-Phosphatidylinositol 4-Kinase; D011505:Protein-Tyrosine Kinases; C494960:Fyn protein, mouse; D051076:Proto-Oncogene Proteins c-fyn; D016392:Proto-Oncogene Proteins pp60(c-src)