Native Human Factor XIIIa protein (Active)

Supplementary info

This supplementary information is collated from multiple sources and compiled automatically.

Activity summary

Factor XIIIa also known as Factor 13a Factor XIII or Factor 13 is an enzyme that plays an important role in blood coagulation. Its mass is approximately 83 kDa. This enzyme is part of the transglutaminase family and is predominantly found in plasma and platelets. Factor XIIIa becomes active when thrombin and calcium ions cleave its A subunits converting it from an inactive zymogen known simply as Factor XIII or Factor 13 to its active form. The best assays for Factor XIIIa often measure its transglutaminase activity which facilitates the cross-linking of fibrin stabilizing blood clots.

Biological function summary

Factor XIIIa is important for hemostasis facilitating the final stages of blood clot formation by cross-linking fibrin polymers. This enzyme does not function in isolation; it forms a tetrameric complex with two A subunits and two B subunits. The active form Factor XIIIa catalyzes the formation of covalent bonds between glutamine and lysine residues in fibrin chains. This enhances the mechanical strength and resistance of the clot preventing premature degradation.

Pathways

Factor XIIIa is part of the coagulation pathway specifically involved in the stabilization of fibrin in the final steps of the cascade. It interacts closely with proteins like fibrinogen and thrombin as these proteins are essential in the conversion of Factor XIII to Factor XIIIa and in clot formation. Factor XIIIa also plays a role in the wound healing process by stabilizing the ECM (extracellular matrix) through cross-linking fibrin fibronectin and collagen.

Associated diseases and disorders

Factor XIIIa deficiency can lead to bleeding diathesis a condition characterized by poor clot stability and prolonged bleeding. This deficiency is often congenital and involves reduced levels or activity of Factor XIII. Conversely overactivity or dysregulation of Factor XIIIa may contribute to thrombotic disorders where abnormal clot formation can lead to conditions like deep vein thrombosis. Clinically understanding Factor XIIIa interactions especially its functional relationships with fibrinogen and thrombin is critical in managing these bleeding and thrombotic disorders.