Title : The influence of N-linked glycosylation on the function of
platelet glycoprotein VI
Abstract :
- Using recombinant human glycoprotein VI ( GPVI ), we evaluated the effect of N-linked glycosylation at the consensus site Asparagine92-Glycine-Serine94 (N92GS94) on binding of this platelet-specific receptor to its ligands, human type I collagen, collagen-related peptide ( CRP ), and the snake venom C-type lectin convulxin ( CVX )
- In COS-7 cells transiently transfected with GPVI , deglycosylation with peptide-N-glycosidase F ( PNGase F; specific for complex N-linked glycans) or tunicamycin decreases the molecular weight of GPVI and reduces transfected COS-7 cell binding to both CRP and CVX
- In stably transfected Dami cells, the substitutions N92A or S94A, but not L95H, resulted in a 30% to 40% decrease in adhesion to CVX , but a 90% or greater decrease in adhesion to CRP and a 65% to 70% decrease in adhesion to type I collagen
- Treatment with PNGase F , but not Endoglycosidase H (Endo H) (specific for high-mannose N-linked glycans), produced an equivalent decrease in molecular weight
- Neither N92A nor S94A affected the expression of GPVI , based on the direct binding of murine anti-human GPVI monoclonal antibody 204-11 to transfected Dami cells
- These findings indicate that N-linked glycosylation at N92 in human GPVI is not required for surface expression, but contributes to maximal adhesion to type I collagen, CRP and, to a lesser extent, CVX
Output (sent_index, trigger,
protein,
sugar,
site):
- 0. glycoprotein, , platelet glycoprotein VI, -, -
- 0. glycosylation, , platelet glycoprotein VI, -, -
- 1. glycoprotein, , glycoprotein VI, -, -
- 1. glycosylation, , receptor, -, -
- 6. glycosylation, , -, -, N92
- 6. glycosylation, , GPVI, -, N92
Output(Part-Of) (sent_index,
protein,
site):
*Output_Site_Fusion* (sent_index,
protein,
sugar,
site):