The Role of ITAM- and ITIM-coupled Receptors in Platelet Activation by Collagen

Steve P. Watson; Naoki Asazuma; Ben Atkinson; Oscar Berlanga; Denise Best; Regis Bobe; Gavin Jarvis; Stuart Marshall; Daniel Snell; Margaret Stafford; David Tulasne; Jonathan Wilde; Peter Wonerow; Jon Frampton

doi:10.1055/s-0037-1616225

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2001; 86(01): 276-288
DOI: 10.1055/s-0037-1616225

Research Article

Schattauer GmbH

The Role of ITAM- and ITIM-coupled Receptors in Platelet Activation by Collagen

Steve P. Watson

¹Departments of Pharmacology, John Radcliffe Hospital, Oxford, UK

,

Naoki Asazuma²

,

Ben Atkinson

,

Oscar Berlanga

,

Denise Best

,

Regis Bobe

,

Gavin Jarvis

,

Stuart Marshall

,

Daniel Snell

,

Margaret Stafford

⁴Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK

,

David Tulasne

,

Jonathan Wilde

,

Peter Wonerow

,

Jon Frampton

⁴Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, UK

› Author Affiliations

Abstract

Summary

The major activation-inducing collagen receptor glycoprotein VI (GPVI) has been cloned within the last two years. It is a member of the Ig superfamily of proteins and is constitutively associated with the ITAM-bearing Fc receptor γ-chain (FcR γ-chain). GPVI signals through a pathway that involves several of the proteins used by Fc, B- and T-lymphocyte receptors and which takes place in glycolipid-enriched membrane domains in the plasma membrane known as GEMs. Responses to GPVI are regulated by PECAM-1 (CD31) and possibly other ITIM-bearing receptors. Despite a pivotal role for GPVI, there are important differences between signalling events to collagen and GPVI-specific ligands. This may reflect a role for co-receptors in the response to collagen.

Key words

Collagen - GPVI - signal transduction - tyrosine phosphorylation - ITAM - ITIM

Full Text

References

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