DNA sequence and characterization of human class II major histocompatibility complex beta chains from the DR1 haplotype.
Two HLA class II beta-chain clones from a cell line homozygous for the DR1 haplotype have been characterized and sequenced. They represent a DR beta chain (2918.4) and a DQ beta chain (2918.8). Clone 2918.4 has been used to select mRNA from a lymphoblastoid cell line, and this was injected into Xenopus oocytes with mRNA selected with a DR alpha chain. The translation products were immunoprecipitated with a beta-chain-specific monoclonal antibody and electrophoresed on two-dimensional gels. This revealed positive signals in the positions predicted for beta and alpha chains. Sequence comparisons of 2918.4 with previously published DR beta-chain sequences confirm the presence of two regions of variability in the membrane distal domain. Analysis of the sequence of 2918.8 identified it as a DQ beta chain identical to one previously published from a DR3,w6 cell line. We speculate, therefore, that the DQ beta sequence represents the DQ1 specificity shared by the DR1 and DRw6 haplotypes.
D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D005260:Female; D005796:Genes; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D007526:Isoelectric Point; D008285:Major Histocompatibility Complex; D008970:Molecular Weight; D009865:Oocytes / Q000502:physiology; D014982:Xenopus laevis / Q000502:physiology
D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D004247:DNA