title: Isolation and amino terminal sequencing of a novel melanoma-associated antigen.
abstract: The biochemical characteristics are described for a melanoma-associated glycoprotein antigen, whose expression depends on stage of tumor progression and melanocytic differentiation. This antigen, identified using a monoclonal antibody which specifically stains melanoma cells in immunoperoxidase assay of fixed tissue sections, is synthesized as a 30,000-Da precursor and then processed to a 30,000- to 60,000-Da sialylated glycoprotein. Two-dimensional gel electrophoresis of the antigen resolved more than 20 forms, heterogeneous in both charge and molecular weight. The kinetics of post-translational processing, the sensitivity of processing to tunicamycin, and the molecular weight of the oligosaccharide chains indicate that the oligosaccharides are N-linked. Amino acid sequencing of the antigen purified by immunoaffinity chromatography and by high-pressure liquid chromatography or polyacrylamide gel electrophoresis allowed the assignment of the first 20 acids.
mesh_terms: D000595:Amino Acid Sequence; D000951:Antigens, Neoplasm; D002460:Cell Line; D006801:Humans; D007457:Iodine Radioisotopes; D008545:Melanoma / Q000276:immunology*; D058950:Melanoma-Specific Antigens; D008970:Molecular Weight; D009363:Neoplasm Proteins / Q000302:isolation & purification*; D011863:Radioimmunoassay
chemical_list: D000951:Antigens, Neoplasm; D007457:Iodine Radioisotopes; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins