title: Cloning of cDNAs and the molecular evolution of a bovine MHC class II DRA gene.
abstract: Two overlapping cDNA clones coding for bovine major histocompatibility complex (MHC) class II antigen DRA chain were isolated and characterized. The full-length cDNA clone, MR1, encoded a primary translated product of 253 amino acids, 24 of which were deduced to be a signal peptide and 229 which formed a mature polypeptide. The amino acid sequences deduced from this clone resembled those of class II A molecules from other species in both size and structure, but no potential consensus site of N-linked glycosylation comparable to those in the human, mouse, rat and swine proteins was found in the alpha 2 domain, as well as ovine and equine DRA molecules. Comparison of amino acid sequences encoded by class II A genes among several species and a dendrogram constructed from these data places the DRA gene and the DQA/DYA genes on two distinct branches of a phylogenetic tree, with bovine DRA and ovine DRA being most similar on the DRA branch.
authors.affiliation: Laboratory of Gene Technology and Safety, Institute of Physical and Chemical Research (RIKEN), Ibaraki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Aida
authors.forename: C
authors.initials: C
authors.lastname: Kohda
authors.forename: A
authors.initials: A
authors.lastname: Morooka
authors.forename: Y
authors.initials: Y
authors.lastname: Nakai
authors.forename: K
authors.initials: K
authors.lastname: Ogimoto
authors.forename: T
authors.initials: T
authors.lastname: Urao
authors.forename: M
authors.initials: M
authors.lastname: Asahina
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D002417:Cattle / Q000235:genetics*; D002460:Cell Line; D003001:Cloning, Molecular; D015723:Gene Library; D005802:Genes, MHC Class II; D006684:HLA-DR Antigens / Q000235:genetics*; D059805:HLA-DR alpha-Chains; D006801:Humans; D008221:Lymphoid Tissue / Q000276:immunology; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid
chemical_list: D006684:HLA-DR Antigens; D059805:HLA-DR alpha-Chains