title: De-N-glycosylation or G82S mutation of RAGE sensitizes its interaction with advanced glycation endproducts.
abstract: Interactions between advanced glycation endproducts (AGE) and the receptor for AGE (RAGE) have been implicated in the development of diabetic vascular complications. RAGE has two N-glycosylation sites in and near the AGE-binding domain, and G82S mutation in the second N-glycosylation motif was recently reported in human. In this study, we examined whether de-N-glycosylation or G82S of RAGE affect its ability to bind AGE and cellular response to AGE. Recombinant wild-type, de-N-glycosylation and G82S RAGE proteins were produced in COS-7 cells, purified and assayed for ligand-binding abilities. De-N-glycosylation at N81 and G82S mutation decreased Kd for glycolaldehyde-derived AGE to three orders of magnitude lower levels compared with wild-type. AGE-induced upregulation of VEGF mRNA was significantly augmented in endothelial cell-derived ECV304 cells expressing de-N-glycosylated and G82S RAGE when compared with wild-type expressor. Exposure to low glucose resulted in the appearance of RAGE proteins of deglycosylated size in wild-type RAGE-expressing cells and significantly enhanced glycolaldehyde-derived AGE-induced VEGF mRNA expression. De-N-glycosylation or G82S mutation of RAGE increases affinity for AGE ligands, and may sensitize cells or conditions with it to AGE.
authors: Department of Biochemistry and Molecular Vascular Biology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa 920-8640, Japan.
authors: Mari
authors: M
authors: Osawa
authors: Yasuhiko
authors: Y
authors: Yamamoto
authors: Seiichi
authors: S
authors: Munesue
authors: Naho
authors: N
authors: Murakami
authors: Shigeru
authors: S
authors: Sakurai
authors: Takuo
authors: T
authors: Watanabe
authors: Hideto
authors: H
authors: Yonekura
authors: Yasuko
authors: Y
authors: Uchigata
authors: Yasuhiko
authors: Y
authors: Iwamoto
authors: Hiroshi
authors: H
authors: Yamamoto
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020349:Surface Plasmon Resonance; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis
chemical_list: D017127:Glycation End Products, Advanced; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D042461:Vascular Endothelial Growth Factor A