title: Two tumor antigens and their polypeptides in adenovirus type 12-infected and transformed cells.
abstract: A tumor (T) antigen, designated T antigen g, was visualized as fine fluorescent granules in nuclei of adenovirus type 12 (Ad12)-infected cells by immunofluorescence with sera from rats bearing HY cell tumors (H sera). HY cells are rat cells incompletely transformed by the Acc I-H endonuclease fragment (0-4.7 map units) of Ad12 DNA. The antigen is different from the usually described T antigen, designated T antigen f, which is visualized as fluorescent flecks or filaments in both nucleus and cytoplasm of Ad12-infected cells when tested with narrowly reacting T sera. Extracts of [(35)S]methioninelabeled infected cells were immunoprecipitated with H sera, and the resultant precipitate was analyzed by the two-dimensional gel electrophoresis technique of O'Farrell. The autoradiogram showed the presence of a cluster of several polypeptides (M(r) 35,000-40,000, pI 5.0-5.5) that was absent in extracts of mock-infected cells. A similar autoradiogram of infected cells analyzed with narrowly reacting T sera showed the presence of a small polypeptide (M(r) 10,000, pI 6.4), that was absent in extracts of mock-infected cells. The results show that M(r) 35,000-40,000 polypeptides are components of T antigen g and a M(r) 10,000 polypeptide is a component of T antigen f. Ad12-transformed cells showed a similar result. T antigen g was present and T antigen f was absent in HY cells. Both T antigen g and T antigen f were present in CY cells, which are rat cells completely transformed by the EcoRI-C endonuclease fragment (0-16 map units) of Ad12 DNA. The possible functions of these proteins are discussed.
mesh_terms: D000257:Adenoviridae Infections / Q000276:immunology*; D000258:Adenovirus Infections, Human / Q000276:immunology*; D000260:Adenoviruses, Human / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000032:analysis*; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D006801:Humans; D008970:Molecular Weight; D009374:Neoplasms, Experimental / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology / Q000302:isolation & purification
chemical_list: D000951:Antigens, Neoplasm; D014764:Viral Proteins