title: Molecular characterization of the human red cell Rho(D) antigen.
abstract: Human red cells of Rh blood groups -D-/-D- ('super-D'), -/- (Rhnull) and normal Rho(D)+ cells were radioactively surface-labeled using the lactoperoxidase 125I method. Polyacrylamide gel electrophoresis in the presence of SDS followed by fluorography showed a strong enrichment of a polypeptide with an apparent mol. wt. of 28,0000-33,000 in the 125I-labeled -D-/-D- membranes. This polypeptide was specifically immune precipitated with anti-Rho(D) antiserum. Treatment of intact cells with trypsin or Pronase did not digest the protein. The Rho polypeptide migrated identically on polyacrylamide gel electrophoresis under reducing and non-reducing conditions. It was not phosphorylated after in vitro incubation of red cells with 32P. When whole labeled membranes were solubilized in neutral detergent and applied to lectin-Sepharose columns the Rho(D) polypeptide adsorbed to Ricinus communis lectin but not to wheat germ lectin or Lens culinaris lectin. The purified molecule did not adsorb to R. communis lectin-Sepharose. Treatment of the Rho(D) antigen with endo-N-acetyl glucosaminidase H, endo-beta-galactosidase or mild alkali did not lower its apparent mol. wt.
authors.affiliation: Department of Biochemistry, University of Helsinki, Finland.
authors.forename: C G
authors.initials: CG
authors.lastname: Gahmberg
mesh_terms: D000468:Alkalies; D002241:Carbohydrates; D002462:Cell Membrane / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004912:Erythrocytes / Q000378:metabolism*; D006026:Glycoside Hydrolases; D006801:Humans; D007457:Iodine Radioisotopes; D007553:Isotope Labeling; D007784:Lactoperoxidase / Q000378:metabolism; D037102:Lectins / Q000378:metabolism; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D010084:Oxidation-Reduction; D010766:Phosphorylation; D011402:Pronase; D011506:Proteins / Q000378:metabolism; D012204:Rh-Hr Blood-Group System / Q000378:metabolism*; D014357:Trypsin; D001616:beta-Galactosidase
chemical_list: D000468:Alkalies; D002241:Carbohydrates; D007457:Iodine Radioisotopes; D037102:Lectins; D011506:Proteins; D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen; D007784:Lactoperoxidase; D006026:Glycoside Hydrolases; C026093:keratan-sulfate endo-1,4-beta-galactosidase; D001616:beta-Galactosidase; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D014357:Trypsin; D011402:Pronase