title: Molecular cloning and primary structure of Kell blood group protein.
abstract: The Kell blood group is a major antigenic system in human erythrocytes. Kell antigens reside on a 93-kDa membrane glycoprotein that is surface-exposed and associated with the underlying cytoskeleton. We isolated tryptic peptides and, based on the amino acid sequence of one of the peptides and by using the PCR, prepared a specific oligonucleotide to screen a lambda gt10 human bone-marrow cDNA library. Four clones were isolated, one containing cDNA with an open reading frame for an 83-kDa protein. All known Kell amino acid sequences were present in the deduced sequence; moreover, rabbit antibody to a 30-amino acid peptide, prepared from this sequence, reacted on an immunoblot with authentic Kell protein. The Kell cDNA sequence predicts a 732-amino acid protein. Hydropathy analysis indicates a single membrane-spanning region, suggesting that Kell protein is oriented with 47 of its N-terminal amino acids in the cell cytoplasm, and a 665-amino acid segment, which contains six possible N-glycosylation sites, is located extracellularly. Computer-based search showed that Kell has structural and sequence homology to a family of zinc metalloglycoproteins with neutral endopeptidase activity.
authors.affiliation: Lindsley F. Kimball Research Institute of the New York Blood Center, NY 10021.
authors.forename: S
authors.initials: S
authors.lastname: Lee
authors.forename: E D
authors.initials: ED
authors.lastname: Zambas
authors.forename: W L
authors.initials: WL
authors.lastname: Marsh
authors.forename: C M
authors.initials: CM
authors.lastname: Redman
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000235:genetics; D000943:Antigens, Differentiation / Q000235:genetics; D000951:Antigens, Neoplasm / Q000235:genetics; D001483:Base Sequence; D015152:Blotting, Northern; D001853:Bone Marrow / Q000276:immunology; D003001:Cloning, Molecular; D015723:Gene Library; D006801:Humans; D007626:Kell Blood-Group System / Q000235:genetics*; D008969:Molecular Sequence Data; D015260:Neprilysin; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction / Q000379:methods; D012313:RNA / Q000235:genetics / Q000302:isolation & purification
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm; D007626:Kell Blood-Group System; D015345:Oligonucleotide Probes; D012313:RNA; D015260:Neprilysin