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Updated: Jul 24, 2026
03:53
Extracellular Vesicle Tissue Factor Activity Assay
Published on: December 29, 2023
Modification of tissue factor by peroxynitrite influences its procoagulant activity
J M Adam1, C Ettelaie, K M Naseem
1Department of Biochemistry and Molecular Biology, Royal Free Hospital School of Medicine, London, UK.
FEBS Letters
|July 14, 1998
Summary
Peroxynitrite modifies tissue factor (TF), a key protein in blood clotting, by nitrating tyrosine residues. This modification reduces TF
Area of Science:
- Biochemistry
- Molecular Biology
- Physiology
Background:
- Peroxynitrite is a reactive nitrogen species formed from nitric oxide and superoxide.
- Protein nitration, particularly of tyrosine residues, is a known modification by peroxynitrite.
- Tissue factor (TF) is a transmembrane protein initiating the coagulation cascade, crucial in hemostasis and thrombosis.
Purpose of the Study:
- To investigate the effect of peroxynitrite on the function of tissue factor (TF).
- To determine if peroxynitrite-mediated modification of TF impacts its procoagulant activity.
Main Methods:
- Exposure of recombinant and cellular TF to peroxynitrite.
- Assay of TF procoagulant activity.
- Quantification of nitrotyrosine residues in TF using biochemical methods.
Main Results:
- Peroxynitrite exposure reduced the procoagulant activity of both recombinant and cellular TF.
- Increased levels of nitrotyrosine residues were observed in TF following peroxynitrite treatment.
- A correlation was found between nitrotyrosine formation and reduced TF activity.
Conclusions:
- Peroxynitrite modifies TF, leading to decreased procoagulant function.
- This suggests a potential protective role for peroxynitrite in attenuating TF-driven thrombosis.
- Nitration of tyrosine residues on TF is the likely mechanism for functional impairment.
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