title: Association of protein phosphatase 2A with polyoma virus medium tumor antigen.
abstract: The polyoma virus medium and small tumor antigens, as well as simian virus 40 small tumor antigen, form specific complexes with two cellular proteins designated 61- and 37-kDa proteins. In this report, we demonstrate that the 61- and 37-kDa proteins correspond to the A and C subunits, respectively, of the serine- and threonine-specific protein phosphatase 2A (PP2A). On the one hand, antibodies raised against the 61-kDa protein reacted specifically with the purified A subunit of PP2A. Furthermore, the amino acid sequences of seven tryptic peptides from the A subunit were almost identical to sequences of the 61-kDa protein as deduced from the corresponding cDNA sequence. On the other hand, antibodies against the purified C subunit (catalytic subunit) of PP2A reacted specifically with the medium tumor antigen-associated 37-kDa protein. These data suggest a role of PP2A in cell transformation by polyoma virus and simian virus 40.
authors.affiliation: Department of Pathology, University of California, San Diego, La Jolla 92093.
authors.forename: G
authors.initials: G
authors.lastname: Walter
authors.forename: R
authors.initials: R
authors.lastname: Ruediger
authors.forename: C
authors.initials: C
authors.lastname: Slaughter
authors.forename: M
authors.initials: M
authors.lastname: Mumby
mesh_terms: D000260:Adenoviruses, Human / Q000201:enzymology / Q000235:genetics* / Q000276:immunology; D000595:Amino Acid Sequence; D000952:Antigens, Polyomavirus Transforming / Q000032:analysis* / Q000276:immunology; D002460:Cell Line; D006801:Humans; D015151:Immunoblotting; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010749:Phosphoprotein Phosphatases / Q000032:analysis / Q000235:genetics* / Q000276:immunology; D054648:Protein Phosphatase 2; D012689:Sequence Homology, Nucleic Acid
chemical_list: D000952:Antigens, Polyomavirus Transforming; D046911:Macromolecular Substances; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2