title: Nucleotide sequences and the molecular evolution of the DMA and DMB genes of the bovine major histocompatibility complex.
abstract: cDNA clones encoding the bovine major histocompatibility complex (MHC) class II DM alpha- and beta-chains were isolated and characterized. The BoLA-DMA cDNA clone, MA7, encoded a primary translated product of 260 amino acids, which included a signal peptide of 26 amino acids and a mature polypeptide of 234 amino acids. The BoLA-DMB cDNA clone, MB6, encoded a primary translated product of 262 amino acids, with a signal peptide of 18 amino acids and a mature polypeptide of 244 amino acids. Comparison of the sequences and construction of a phylogenetic tree revealed that both clones are more closely related to human and mouse DM genes than to genes for conventional bovine class II alpha- and beta-chains. Thus, since the bovine DMA and DMB genes are so different from other class II sequences and show evidence of strong conservation (> 70%) among the bovine, mouse and human homologues, it seems likely that each of these cDNA clones encodes a functional product, which might perform an important function, as previously established in studies in mouse and man.
authors.affiliation: Laboratory of Gene Technology and Safety, Tsukuba Life Science Center, Institute of Physical and Chemical Research (RIKEN), Ibaraki, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Niimi
authors.forename: Y
authors.initials: Y
authors.lastname: Nakai
authors.forename: Y
authors.initials: Y
authors.lastname: Aida
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics* / Q000276:immunology; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000235:genetics; D005802:Genes, MHC Class II; D006801:Humans; D008285:Major Histocompatibility Complex; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D017931:DNA Primers; D018076:DNA, Complementary