title: Immunochemical evidence in two haplotypes for at least three D region-encoded molecules, D, L, and R.
abstract: Sequential immunoprecipitation analyses have defined a new transplantation antigen, designated R, which in addition to the 2 previously isolated D and L molecules is encoded in the D region. All 3 of these gene products are 45,000 m.w. glycoprotein, and each bears a unique combination of specificities as recognized by monoclonal and/or conventional anti-H-2 sera. Three D region products, D, L, and R, have now been isolated from soluble antigens of both the H-2d and H-2q haplotypes. The resulted reported here also indicate that the loss-mutant BALB/c-H-2dm2 fails to express both Ld and Rd antigens. Further chemical comparisons of the primary structure of R molecules with D and L molecules will now be necessary to determine whether R antigens are the products of a unique gene, as opposed to a glycosylation or conformational variant of D and/or L molecules. In either case, the discovery of 3 D region-encoded gene products in certain haplotypes raises new questions about the evolution and regulation of expression of H-2 loci.
mesh_terms: D000818:Animals; D011232:Chemical Precipitation; D002874:Chromosome Mapping; D002999:Clone Cells / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D005815:Genetic Code; D006238:Haploidy; D006649:Histocompatibility Antigens / Q000235:genetics*; D007106:Immune Sera / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D014176:Protein Biosynthesis
chemical_list: D006649:Histocompatibility Antigens; D007106:Immune Sera