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Updated: Jul 28, 2026

Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells
10:10

Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells

Published on: October 27, 2009

Crystal structure of the GpIbalpha-thrombin complex essential for platelet aggregation

John J Dumas1, Ravindra Kumar, Jasbir Seehra

  • 1Department of Chemical and Screening Sciences, Wyeth, 200 Cambridge Park Drive, Cambridge, MA 02140, USA.

Science (New York, N.Y.)
|July 12, 2003
PubMed

Direct interaction between platelet receptor glycoprotein Ibalpha (GpIbalpha) and thrombin is required for platelet aggregation and activation at sites of vascular injury. Abnormal GpIbalpha-thrombin binding is associated with many pathological conditions,including occlusive arterial thrombosis and bleeding disorders. The crystal structure of the GpIbalpha-thrombin complex at 2.6 angstrom resolution reveals simultaneous interactions of GpIbalpha with exosite I of one thrombin molecule,and with exosite II of a second thrombin molecule. In the crystal lattice,the periodic arrangement of GpIbalpha-thrombin complexes mirrors a scaffold that could serve as a driving force for tight platelet adhesion. The details of these interactions reconcile GpIbalpha-thrombin binding modes that are presently controversial,highlighting two distinct interfaces that are potential targets for development of novel antithrombotic drugs.

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