The snake venom toxin alboaggregin-A activates glycoprotein VI.
The glycoprotein (GP)-Ib-IX-V receptor complex has recently been reported to signal through a pathway similar to that used by the collagen receptor GPVI, with a critical role described for the Fc receptor gamma-chain. The evidence for this was based in part on studies with the GPIbalpha-selective snake venom toxin, alboaggregin-A. In the present study, it is reported that alboaggregin-A has activity at the collagen receptor GPVI in addition to GPIbalpha, and evidence is provided that this contributes to protein tyrosine phosphorylation, shape change, and GPIIb-IIIa-dependent aggregation. This may explain why responses to alboaggregin-A are distinct from those to von Willebrand factor-ristocetin. (Blood. 2001;97:3989-3991)
Asazuma
N
N
Department of Pharmacology, University of Oxford, Mansfield Rd., Oxford, OX1 3QT, United Kingdom.
Marshall
S J
SJ
Berlanga
O
O
Snell
D
D
Poole
A W
AW
Berndt
M C
MC
Andrews
R K
RK
Watson
S P
SP
D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects; D003435:Crotalid Venoms / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D010766:Phosphorylation / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000494:pharmacology; D010980:Platelet Membrane Glycoproteins / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D014443:Tyrosine / Q000378:metabolism
D003435:Crotalid Venoms; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D010980:Platelet Membrane Glycoproteins; C112003:alboaggregin A; C098341:platelet membrane glycoprotein VI; D014443:Tyrosine