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Updated: Jun 23, 2026
12:24
Helical Organization of Blood Coagulation Factor VIII on Lipid Nanotubes
Published on: June 3, 2014
Coagulation factor XIII serves as protein disulfide isomerase
Judith Lahav1, Eli Karniel, Zsuzsa Bagoly
1Thrombosis and Hemostasis Unit, Beilinson Hospital, Rabin Medical Center, Petah Tikva, Israel.
Thrombosis and Haemostasis
|May 1, 2009
Summary
Coagulation factor XIII (FXIII), a plasma transglutaminase, exhibits protein disulfide isomerase (PDI) activity, similar to tissue transglutaminase. This FXIII-PDI function, independent of its transglutaminase role, may influence platelet function.
Area of Science:
- Biochemistry
- Hematology
- Enzymology
Background:
- Tissue transglutaminase (TG) possesses protein disulfide isomerase (PDI) activity.
- The enzymatic function of coagulation factor XIII (FXIII), a plasma TG, in relation to PDI activity is unexplored.
Purpose of the Study:
- To investigate whether plasma FXIII exhibits PDI activity.
- To characterize the nature and potential function of FXIII's PDI activity.
Main Methods:
- Assessed PDI activity by measuring the renaturation of reduced-denatured RNase (rdRNase).
- Evaluated the effect of bacitracin on FXIII's PDI activity.
- Determined the subunit responsible for PDI activity.
Main Results:
- FXIII demonstrated significant PDI activity, comparable to commercial PDI.
- This activity was inhibited by bacitracin.
- FXIII's PDI activity is independent of its transglutaminase function and resides on the A subunit.
Conclusions:
- Plasma FXIII possesses intrinsic PDI activity.
- This FXIII-PDI activity may play a role in platelet function, potentially through disulfide bond rearrangement.
- Findings suggest a novel function for FXIII beyond coagulation.
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