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Updated: Aug 13, 2026
12:24
Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes
Published on: June 3, 2014
Proposed structural models of the prothrombinase (FXa-FVa) complex
Ludovic Autin1, Mårten Steen, Björn Dahlbäck
1INSERM U648, University Paris V, Paris, France.
Proteins
|January 27, 2006
Summary
Researchers modeled the activated coagulation factor V (FVa) and factor Xa (FXa) complex using computational docking. One model accurately reflects experimental data, aiding future studies on this crucial blood clotting interaction.
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- Activated coagulation factor V (FVa) acts as a cofactor for factor Xa (FXa) in prothrombin (PT) to thrombin conversion.
- The precise structural and functional mechanisms of the FXa-FVa complex remain incompletely understood despite extensive research.
Purpose of the Study:
- To elucidate the three-dimensional structure of the human factor Xa-factor Va complex.
- To develop a reliable computational model of the FXa-FVa interaction.
Main Methods:
- Protein:protein (Pr:Pr) docking simulations were performed using the ICM package and the PPD program.
- A novel model of full-length human FVa was utilized alongside the X-ray structure of human FXa.
- A hybrid approach combining theoretical docking with experimental data was employed.
Main Results:
- Five representative models of the FXa-FVa complex were generated.
- One model demonstrated strong consistency with a comprehensive set of existing experimental findings.
- The results highlight the importance of integrating theoretical and experimental methods for large macromolecular complexes.
Conclusions:
- A validated structural model of the FXa-FVa complex has been successfully created.
- This model serves as a critical tool for future investigations into the coagulation cascade.
- The model will guide subsequent site-directed mutagenesis experiments to further probe protein interactions.
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