PMID: 20089867 , Related PDB ids: 3HNB, 3HNY, 3HOB

Authors:

Liu Z, Lin L, Yuan C, Nicolaes GA, Chen L, Meehan EJ, Furie B, Furie B, Huang M

Title:

Trp2313-His2315 of factor VIII C2 domain is involved in membrane binding: structure of a complex between the C2 domain and an inhibitor of membrane binding.

Journal:

J Biol Chem. 2010 Mar 19;285(12):8824-9. Epub 2010 Jan 20.

Abstract:

Factor VIII (FVIII) plays a critical role in blood coagulation by forming the tenase complex with factor IXa and calcium ions on a membrane surface containing negatively charged phospholipids. The tenase complex activates factor X during blood coagulation. The carboxyl-terminal C2 domain of FVIII is the main membrane-binding and von Willebrand factor-binding region of the protein. Mutations of FVIII cause hemophilia A, whereas elevation of FVIII activity is a risk factor for thromboembolic diseases. The C2 domain-membrane interaction has been proposed as a target of intervention for regulation of blood coagulation. A number of molecules that interrupt FVIII or factor V (FV) binding to cell membranes have been identified through high throughput screening or structure-based design. We report crystal structures of the FVIII C2 domain under three new crystallization conditions, and a high resolution (1.15 A) crystal structure of the FVIII C2 domain bound to a small molecular inhibitor. The latter structure shows that the inhibitor binds to the surface of an exposed beta-strand of the C2 domain, Trp(2313)-His(2315). This result indicates that the Trp(2313)-His(2315) segment is an important constituent of the membrane-binding motif and provides a model to understand the molecular mechanism of the C2 domain membrane interaction.