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Related Experiment Video

Updated: Jun 16, 2026

Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

Published on: June 3, 2014

Structure and function of factor XI.

Jonas Emsley¹, Paul A McEwan, David Gailani

¹School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK.

|January 30, 2010

Summary

This summary is machine-generated.

Factor XI (FXI) is an unusual protease involved in blood clotting. New structural insights reveal its role in thrombosis, aiding the development of new therapies for blood disorders.

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Last Updated: Jun 16, 2026

Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes

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Published on: June 3, 2014

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

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Published on: September 9, 2012

Extracellular Vesicle Tissue Factor Activity Assay

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Published on: December 29, 2023

Area of Science:

Biochemistry
Molecular Biology
Hematology

Background:

Factor XI (FXI) is a key enzyme in hemostasis, activating factor IX.
FXI deficiency causes mild bleeding, but FXI also contributes to thrombosis and dysregulated coagulation.
FXI is a unique dimeric protease distinct from other vitamin K-dependent coagulation proteases.

Purpose of the Study:

To elucidate the structure-function relationships of Factor XI.
To understand the mechanism of FXI activation and its interactions.
To explore FXI's role in thrombotic disorders.

Main Methods:

Analysis of crystal structures of zymogen FXI and the FXIa catalytic domain.
Characterization of the FXI apple disk structure and its relation to the catalytic domain.
Analysis of missense mutations associated with FXI deficiency.

Main Results:

Detailed structural features of FXI, including its 4 apple domains forming a disk structure.
New insights into FXI activation mechanism, FXIa-factor IX interaction, and FXI-platelet binding.
Identification of potential ligand-binding sites on the FXI protein surface.

Conclusions:

Structural data enhances understanding of FXI physiology and pathology.
Findings facilitate the development of therapeutics for thrombotic disorders.
FXI's role in thrombosis warrants further investigation for therapeutic targeting.