title: Structure and biosynthesis of histocompatibility antigens (H-2, HLA).
abstract: Histocompatibility antigens (H-2K, D and L, and HLA-A, B and C) are highly polymorphic cell surface proteins. Their primary structure has been determined by sequencing the protein, complementary DNAs (cDNAs) or genes in several laboratories. H-2Ld and Kd antigens are encoded by eight separate exons: one encodes the signal sequence, three encode the external domains, one encodes the membrane spanning segment and three encode the cytoplasmic domain. A similar structural organization has been found for an HLA gene. H-2 and HLA antigens are synthesized on membrane-bound ribosomes and are co-translationally inserted into the membrane of the endoplasmic reticulum. Here they assemble with beta 2-microglobulin, a small secretory protein. We describe the structure, the membrane insertion in vitro and in vivo, the intracellular transport and the surface expression of these antigens.
mesh_terms: D000818:Animals; D001692:Biological Transport; D006023:Glycoproteins / Q000096:biosynthesis*; D006183:H-2 Antigens; D006680:HLA Antigens; D006801:Humans; D046911:Macromolecular Substances; D008565:Membrane Proteins / Q000096:biosynthesis*; D051379:Mice; D011487:Protein Conformation; D001613:beta 2-Microglobulin / Q000378:metabolism
chemical_list: D006023:Glycoproteins; D006183:H-2 Antigens; D006680:HLA Antigens; D046911:Macromolecular Substances; D008565:Membrane Proteins; D001613:beta 2-Microglobulin