Molecular identity and cellular distribution of advanced glycation endproduct receptors: relationship of p60 to OST-48 and p90 to 80K-H membrane proteins

Proc Natl Acad Sci U S A. 1996 Oct 1;93(20):11047-52. doi: 10.1073/pnas.93.20.11047.

Abstract

Advanced glycation endproducts (AGEs) are derivatives of nonenzymatic reactions between sugars and protein or lipids, and together with AGE-specific receptors are involved in numerous pathogenic processes associated with aging and hyperglycemia. Two of the known AGE-binding proteins isolated from rat liver membranes, p60 and p90, have been partially sequenced. We now report that the N-terminal sequence of p60 exhibits 95% identity to OST-48, a 48-kDa member of the oligosaccharyltransferase complex found in microsomal membranes, while sequence analysis of p90 revealed 73% and 85% identity to the N-terminal and internal sequences, respectively, of human 80K-H, a 80- to 87-kDa protein substrate for protein kinase C. AGE-ligand and Western analyses of purified oligosaccharyltransferase complex, enriched rough endoplasmic reticulum, smooth endoplasmic reticulum, and plasma membranes from rat liver or RAW 264.7 macrophages yielded a single protein of approximately 50 kDa recognized by both anti-p60 and anti-OST-48 antibodies, and also exhibited AGE-specific binding. Immunoprecipitated OST-48 from rat rough endoplasmic reticulum fractions exhibited both AGE binding and immunoreactivity to an anti-p60 antibody. Immune IgG raised to recombinant OST-48 and 80K-H inhibited binding of AGE-bovine serum albumin to cell membranes in a dose-dependent manner. Immunostaining and flow cytometry demonstrated the surface expression of OST-48 and 80K-H on numerous cell types and tissues, including mononuclear, endothelial, renal, and brain neuronal and glial cells. We conclude that the AGE receptor components p60 and p90 are identical to OST-48, and 80K-H, respectively, and that they together contribute to the processing of AGEs from extra- and intracellular compartments and in the cellular responses associated with these pathogenic substances.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Calcium-Binding Proteins
  • Cell Line
  • Cell Membrane / metabolism
  • Endoplasmic Reticulum, Rough / metabolism
  • Fluorescent Antibody Technique, Indirect
  • Glucosidases
  • Glycation End Products, Advanced / metabolism*
  • Hexosyltransferases*
  • Humans
  • Intracellular Signaling Peptides and Proteins*
  • Male
  • Membrane Proteins / metabolism
  • Mice
  • Molecular Sequence Data
  • Myristoylated Alanine-Rich C Kinase Substrate
  • Phosphoproteins / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Receptor for Advanced Glycation End Products
  • Receptors, Immunologic / metabolism*
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Transferases / metabolism*

Substances

  • Calcium-Binding Proteins
  • Glycation End Products, Advanced
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • Phosphoproteins
  • Prkcsh protein, mouse
  • Prkcsh protein, rat
  • Receptor for Advanced Glycation End Products
  • Receptors, Immunologic
  • Myristoylated Alanine-Rich C Kinase Substrate
  • Transferases
  • Hexosyltransferases
  • dolichyl-diphosphooligosaccharide - protein glycotransferase
  • Glucosidases
  • PRKCSH protein, human