Methods of detecting mature human Ia-like antigen and their metabolic precursors.
Ia antigens were shown to be present in the cell almost exclusively as mature alpha beta dimers which split into separate alpha and beta chains after boiling in SDS. In contrast metabolically labelling the cells with [35S]methionine resulted in only free alpha and beta chains being labelled. It is concluded that this widely used type of labelling, although useful for studying intermediate synthesis, should not be used for labelling mature cell surface molecules.
D002250:Carbon Radioisotopes; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D007930:Leucine / Q000378:metabolism; D007945:Leukemia, Lymphoid / Q000276:immunology; D046911:Macromolecular Substances; D008715:Methionine / Q000378:metabolism; D008970:Molecular Weight; D011498:Protein Precursors / Q000032:analysis*; D011865:Radioisotope Dilution Technique; D013462:Sulfur Radioisotopes
D002250:Carbon Radioisotopes; D000949:Histocompatibility Antigens Class II; D046911:Macromolecular Substances; D011498:Protein Precursors; D013462:Sulfur Radioisotopes; D008715:Methionine; D007930:Leucine