Effects of Val34Leu and Val35Leu polymorphism on the enzyme activity of the coagulation factor XIII-A.
- Author:
Il Ha LEE
1
;
Soo Il CHUNG
;
Soo Young LEE
Author Information
1. Department of Natural Sciences Chemistry Section, College of Medicine, The Catholic University of Korea, Seoul, Korea. lsyng@catholic.ac.kr
- Publication Type:Original Article
- Keywords:
Factor XIII;
Val34Leu;
Val35Leu;
catalytic efficiency;
site-directed mutagensis
- MeSH:
Blood Coagulation Tests;
Catalysis;
Enzyme Activation/genetics;
Escherichia coli/genetics;
Factor XIII/*genetics/*metabolism;
Fibrin/metabolism;
Human;
Immunoblotting;
Leucine/genetics;
Mutagenesis, Site-Directed;
*Polymorphism (Genetics);
Recombinant Proteins/genetics/metabolism;
Thrombin/metabolism;
Valine/genetics
- From:Experimental & Molecular Medicine
2002;34(5):385-390
- CountryRepublic of Korea
- Language:English
-
Abstract:
Change in fibrin stabilizing activity of factor XIII A subunit (FXIII-A) caused by a specific mutation, Val34Leu, is recently implicated to incidences of pathophysiology of thrombosis. In an effort to understand the effect of Val34Leu on enhanced catalytic role of FXIII-A, wild type human factor XIII A (HFXIII-A) and mutant HFXIII-A: HFXIII-A (V34L), HFXIII-A (V35L) and HFXIII-A (V34L/V35L) cDNA were expressed in E.coli system where the purified recombinant FXIII-A (rFXIII-A) showed a similar specific transglutaminase activity comparable to the human native FXIII-A from platelet. Using these rFXIII-A mutants, the activation kinetics by thrombin and the enzymatic properties of the activated rFXIII-A were characterized. rFXIII-A (V34L) and rFXIII-A (V34L/V35L) mutants were activated by thrombin much faster than those of wild type rFXIII-A and V35L variant. However, the activated rFXIII-A and mutants showed the identical catalytic efficiency as measured by in vitro assay. These results suggest that ready activation caused by a specific mutation of neighboring thrombin cleavage site(s) in the activation peptide of FXIII-A like V34L resulted in the real-time amount of the activated factor XIII-A that could influence the outcome of fibrin stabilization in vivo such as alpha2- plasmin inhibitor crosslinking to fibrin, a reaction known to be dependent on the initial concentration of active factor-XIII-A.
