title: Mouse heparin binding protein-44 (HBP-44) associates with brushin, a high-molecular-weight glycoprotein antigen common to the kidney and teratocarcinomas.
abstract: Heparin binding protein-44 (HBP-44) is a heparin binding protein of 44 kDa, found by cDNA cloning using antibodies against teratocarcinoma glycoproteins [Furukawa, T. et al. (1990) J. Biochem. 108, 297-302]. The N-terminal sequence analysis reported in this publication establishes the structure of its mature form. Immunohistochemical staining revealed that HBP-44 was located in the tubular brush border of the kidney. HBP-44 formed a complex with brushin, a high molecular weight (450 kDa) glycoprotein antigen common to the kidney and teratocarcinoma, but not with OR8 antigen, another antigen (350 kDa) of the same category. Brushin was shown to be the mouse counterpart of rat Heymann nephritis antigen, called gp330. The association between HBP-44 and brushin was revealed not only by co-precipitation upon indirect immunoprecipitation, but also by ligand blotting with HBP-44-maltose binding protein fusion protein. Calcium ion stabilized the association. Disulfide bonds in brushin seemed to be necessary for the complex formation, since reductive cleavage of the bonds resulted in failure of the protein to associate with HBP-44 in a ligand blotting experiment. Association of HBP-44 with brushin occurred both in teratocarcinoma cells, in which these molecules are mainly located in extraembryonic endoderm cells, and in the kidney, suggesting that the complex has an unknown common function in the renal tubular brush border and the extraembryonic endoderm.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Kagoshima University.
authors.forename: M
authors.initials: M
authors.lastname: Nakamoto
authors.forename: M
authors.initials: M
authors.lastname: Ozawa
authors.forename: S D
authors.initials: SD
authors.lastname: Jacinto
authors.forename: T
authors.initials: T
authors.lastname: Furukawa
authors.forename: Y
authors.initials: Y
authors.lastname: Natori
authors.forename: H
authors.initials: H
authors.lastname: Shirahama
authors.forename: S
authors.initials: S
authors.lastname: Yonezawa
authors.forename: T
authors.initials: T
authors.lastname: Nakayama
authors.forename: T
authors.initials: T
authors.lastname: Muramatsu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000941:Antigens / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology*; D001483:Base Sequence; D002118:Calcium / Q000494:pharmacology; D002352:Carrier Proteins / Q000276:immunology*; D002460:Cell Line; D004533:Egtazic Acid; D026541:Heymann Nephritis Antigenic Complex; D007668:Kidney / Q000276:immunology*; D026563:LDL-Receptor Related Protein-Associated Protein; D026561:Low Density Lipoprotein Receptor-Related Protein-2; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010980:Platelet Membrane Glycoproteins / Q000276:immunology*; D018243:Teratocarcinoma / Q000276:immunology*; D014407:Tumor Cells, Cultured
chemical_list: D000941:Antigens; D000951:Antigens, Neoplasm; D002352:Carrier Proteins; D026541:Heymann Nephritis Antigenic Complex; D026563:LDL-Receptor Related Protein-Associated Protein; D026561:Low Density Lipoprotein Receptor-Related Protein-2; C055127:Lrp2 protein, mouse; D008562:Membrane Glycoproteins; D010980:Platelet Membrane Glycoproteins; D004533:Egtazic Acid; D002118:Calcium