Characterisation of the N-linked oligosaccharides of the light chain of human glycoprotein IIb by f.a.b.-m.s.
The glycosylation of the light chain (GPIIbL) of glycoprotein IIb, one of the glycoproteins constituting the receptor for fibrinogen, fibronectin, and the von Willebrand factor on platelet cell surfaces, was investigated using fast-atom-bombardment mass spectrometry (f.a.b.-m.s.). Complex-type N-glycans were observed, attached to Asn-60. The most abundant oligosaccharide is a disialylated biantennary structure substituted with fucose on the chitobiose core. Mono-sialylated biantennary, and di- and tri-sialylated triantennary structures were found as minor constituents of the N-glycan population. The amino acid sequence of GPIIbL was fully mapped by f.a.b.-m.s., thereby providing the first direct evidence for the absence of O-glycosylation.
Reason
A J
AJ
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, Great Britain.
Dell
A
A
Morris
H R
HR
Rogers
M E
ME
Calvete
J J
JJ
González-Rodríguez
J
J
D000595:Amino Acid Sequence; D002240:Carbohydrate Sequence; D002918:Chymotrypsin / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000737:chemistry*; D008745:Methylation; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D010980:Platelet Membrane Glycoproteins / Q000737:chemistry*; D011946:Receptors, Antigen / Q000737:chemistry; D011956:Receptors, Cell Surface / Q000737:chemistry*; D017469:Receptors, Fibronectin; D011971:Receptors, Immunologic / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014357:Trypsin / Q000378:metabolism
D016023:Integrins; D009844:Oligosaccharides; D010446:Peptide Fragments; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D010980:Platelet Membrane Glycoproteins; D011946:Receptors, Antigen; D011956:Receptors, Cell Surface; D017469:Receptors, Fibronectin; D011971:Receptors, Immunologic; C028254:von Willebrand factor receptor; D002918:Chymotrypsin; D014357:Trypsin