Thromb Haemost 2002; 88(01): 74-82
DOI: 10.1055/s-0037-1613157
Review Article
Schattauer GmbH

Model of a Ternary Complex between Activated Factor VII, Tissue Factor and Factor IX

Shu-wen W. Chen
,
Jean-Luc Pellequer
1   CEA Valrhô – Site de Marcoule. DSV/DIEP/SBTN, Bagnols-sur-Cèze, France
2   The Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA, USA
,
Jean-François Schved
3   Laboratoire d’hématologie, CHU Saint-Eloi, Montpellier, France
,
Muriel Giansily-Blaizot
3   Laboratoire d’hématologie, CHU Saint-Eloi, Montpellier, France
› Author Affiliations
Further Information

Publication History

Received 02 December 2001

Accepted after revision 04 April 2002

Publication Date:
09 December 2017 (online)

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Summary

Upon binding to tissue factor, FVIIa triggers coagulation by activating vitamin K-dependent zymogens, factor IX (FIX) and factor X (FX). To understand recognition mechanisms in the initiation step of the coagulation cascade, we present a three-dimensional model of the ternary complex between FVIIa:TF:FIX. This model was built using a full-space search algorithm in combination with computational graphics. With the known crystallographic complex FVIIa:TF kept fixed, the FIX docking was performed first with FIX Gla-EGF1 domains, followed by the FIX protease/EGF2 domains. Because the FIXa crystal structure lacks electron density for the Gla domain, we constructed a chimeric FIX molecule that contains the Gla-EGF1 domains of FVIIa and the EGF2-protease domains of FIXa. The FVIIa:TF:FIX complex has been extensively challenged against experimental data including site-directed mutagenesis, inhibitory peptide data, haemophilia B database mutations, inhibitor antibodies and a novel exosite binding inhibitor peptide. This FVIIa:TF:FIX complex provides a powerful tool to study the regulation of FVIIa production and presents new avenues for developing therapeutic inhibitory compounds of FVIIa:TF:substrate complex.