Intracellular factor XIII crosslinks platelet cytoskeletal elements upon platelet activation
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Updated: Sep 29, 2026

Comprehensive Analysis of Procoagulant Platelets Exhibiting Features of Necrosis, Apoptosis and Platelet Activation
Published on: May 23, 2025
Katherine Serrano1, Dana V Devine
1Departments of Biochemistry and Molecular Biology, Canadian Blood Services, UBC-Pathology, 2211 Wesbrook Mall, Vancouver, BC, Canada V6T-2B5.
Abstract:
The platelet cytoplasm contains approximately half of the factor XIII (FXIII) transglutaminase content circulating in blood, yet the function of cytoplasmic FXIII is poorly understood. This study investigated functions of platelet FXIII in internal platelet processes by studying the interactions of FXIII with platelet cytoskeletal proteins. FXIII was present in cytoskeletal fractions of platelet lysate separated by centrifugation. When cytoskeletal fractions were immobilized on nitrocellulose membranes, thrombin-activated rFXIII (rFXIIIa*) or calcium ion-treated rFXIII (rFXIIIa degree) bound to some of these proteins, whereas untreated rFXIII did not. Utilizing fluorescence microscopy, an actin polymerization-dependent transient translocation of FXIII from a diffuse homogeneous distribution throughout the cytoplasm to the platelet periphery was observed upon platelet activation, suggesting an association with cytoskeletal proteins. Transglutaminase activity increased in cytoskeletal fractions of activated versus non-activated platelets. Immunoblotting analysis of platelet cytoskeletal fractions identified filamin and vinculin as being crosslinked upon platelet activation.
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