title: Characterization of the immunoglobulin A heavy chain gene of the Atlantic bottlenose dolphin (Tursiops truncatus).
abstract: Immunoglobulin constant region heavy chain genes of the dolphin (Tursiops truncatus) have been described for IgM and IgG but not for IgA. Here, the heavy chain sequence of dolphin IgA has been cloned and sequenced as cDNA. RT-PCR amplification from blood peripheral lymphocytes was carried out using degenerate primers and a single sequence was detected. The inferred heavy chain structure shows conserved features typical of mammalian IgA heavy chains, including three constant (C) regions, a hinge region between constant region domain 1 (C1) and constant region domain 2 (C2), and conserved residues for interaction with the Fc alpha R1 and N-glycosylation sites. Comparisons of the deduced amino acid sequences of the IgA heavy chain for the dolphin and the evolutionarily related artiodactyl species showed high similarity. In cattle and sheep, as in dolphins, a single IgA subclass has been identified. Southern blot analysis as well as genomic PCR confirmed the presence of multiple IGHA sequences suggesting that IGHA pseudogenes may be present in the dolphin genome.
authors.affiliation: Marine Biomedicine and Environmental Science Center, Medical University of South Carolina, Charleston, SC 29412, USA. mancia@musc.edu
authors.forename: Annalaura
authors.initials: A
authors.lastname: Mancia
authors.forename: Tracy A
authors.initials: TA
authors.lastname: Romano
authors.forename: Holly A
authors.initials: HA
authors.lastname: Gefroh
authors.forename: Robert W
authors.initials: RW
authors.lastname: Chapman
authors.forename: Darlene L
authors.initials: DL
authors.lastname: Middleton
authors.forename: Gregory W
authors.initials: GW
authors.lastname: Warr
authors.forename: Mats L
authors.initials: ML
authors.lastname: Lundqvist
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D050681:Bottle-Nosed Dolphin / Q000235:genetics* / Q000276:immunology; D003001:Cloning, Molecular; D007070:Immunoglobulin A / Q000737:chemistry / Q000235:genetics*; D007127:Immunoglobulin Constant Regions / Q000737:chemistry / Q000235:genetics; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D007070:Immunoglobulin A; D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains