Coagulation, the process of clot formation, involves platelet and blood clotting factors. In humans, the coagulation mechanism is comprised of two processes, i.e. the primary hemostasis and the secondary hemostasis. The latter entails two pathways: (1) intrinsic pathway (contact activation pathway) and (2) extrinsic pathway (tissue factor pathway). Both pathways lead to the formation of fibrin.
Factor X (also called Stuart-Prower factor) is a serine endopeptidase. It is produced in the liver. In humans, it is coded by the factor X gene located on chromosome 13 (particularly 13q34).
Factor X is activated by factor IX (Christmas factor) and factor VIII (anti-hemoplytic factor) through hydrolysis. The activated form, i.e. factor Xa, converts clotting factor II (prothrombin) into clotting factor IIa (thrombin). It does so when it forms a complex with the activated form of clotting factor V (proaccelerin). It cleaves prothrombin at arg-thr bond and arg-ile bond.
Genetic disorder associated with factor X is called congenital Factor X deficiency, a rare disorder characterized by nosebleeds, hemarthrosis, and gastrointestinal blood loss due to a lack in the production of factor X.
- Stuart factor
- Stuart-Prower factor
- (blood) clotting factor X
- (blood) coagulation factor X