Prothrombin (Coagulation factor II) (F2)

Prothrombin (Coagulation factor II) is the inactive zymogen precursor of thrombin, the primary effector of blood coagulation [1]. Pro-exosite I is a discrete binding domain on the prothrombin molecule that serves as the precursor to the anion-binding exosite I found on active thrombin [2]. This site plays a pivotal role in the assembly of the prothrombinase complex, specifically by mediating the interaction between prothrombin and its cofactor, Factor Va [2]. By facilitating this interaction, pro-exosite I ensures the rapid and localized conversion of prothrombin to thrombin at the site of vascular injury [1, 2]. Therapeutic targeting of pro-exosite I, such as with specific DNA aptamers like HD1, aims to inhibit thrombin generation at its source [3, 4]. This approach potentially offers a clinical advantage over direct thrombin inhibitors by providing a more nuanced modulation of the coagulation cascade, potentially reducing the risk of systemic bleeding while maintaining effective antithrombotic activity [2, 3].

Other names

Factor IICoagulation factor IIPro-exosite 1Anion-binding exosite 1 precursor

Inhibition of the prothrombinase complex assembly by blocking the interaction between prothrombin's pro-exosite I and Factor Va, thereby preventing the conversion of prothrombin to thrombin [2, 3].