Platelet glycoprotein VI: its structure and function

Thromb Res. 2004;114(4):221-33. doi: 10.1016/j.thromres.2004.06.046.


Glycoprotein (GP) VI is a platelet membrane protein with a molecular weight of 62 kDa that was identified as a physiological collagen receptor from studies of patients deficient in this protein. GPVI-deficient platelets lacked specifically collagen-induced aggregation and the ability to form thrombi on a collagen surface under flow conditions, suggesting that GPVI makes an indispensable contribution to collagen-induced platelet activation. On the platelet surface, GPVI is present as a complex with the Fc receptor (FcR) gamma-chain, probably composed of two GPVI molecules and one FcR gamma-chain dimer. GPVI must form such a dimeric complex to exhibit high affinity binding to collagen. The GPVI-induced activation mechanism is initiated by tyrosine phosphorylation of the immunoreceptor tyrosine-based activation motif (ITAM) of the FcR gamma-chain, and then this signal is transduced to many related proteins, mainly by tyrosine phosphorylation. GPVI is widely recognized as a requisite factor for the formation of platelet aggregates on a collagen surface under blood flow. However, individuals with GPVI-deficient or null platelets do not exhibit any strong bleeding tendency. Analyzing this apparent dichotomy should provide us with a more precise understanding of the mechanism of thrombus formation.

Publication types

  • Review

MeSH terms

  • Animals
  • Collagen / metabolism
  • Hemorrhage / etiology
  • Humans
  • Platelet Activation
  • Platelet Membrane Glycoproteins / chemistry*
  • Platelet Membrane Glycoproteins / deficiency
  • Platelet Membrane Glycoproteins / metabolism
  • Platelet Membrane Glycoproteins / physiology*
  • Signal Transduction


  • Platelet Membrane Glycoproteins
  • platelet membrane glycoprotein VI
  • Collagen