ⓘ F13B

                                     

ⓘ F13B

Coagulation factor XIII B chain is a protein that in humans is encoded by the F13B gene.

This gene encodes the coagulation factor XIII subunit. Coagulation factor XIII is the last zymogen activating in the blood coagulation cascade. Plasma factor XIII is a heterotetramer composed of 2 A subunits and 2 B subunits. A subunits have catalytic function, and the B subunits do not have enzymatic activity and may serve as the molecules of the plasma of the carrier. Platelet factor XIII is composed of just 2 a subunits, which are identical to the plasma origin. After activation, the cleavage of the activation peptide by thrombin in the presence of calcium ions in the plasma factor XIII dissociates its subunits and yields the same active enzyme, factor XIIIa, as platelet factor XIII. This enzyme acts as an enzyme transglutaminase to catalyze the formation of gamma-glutamyl-Epsilon-lysine crosslinking between fibrin molecules that stabilize a clot of fibrin. Deficiency of factor XIII is divided into two categories: type I deficiency, characterized by the absence of both subunits a I, and type II deficiency, characterized by the absence of a single Department. These defects can result in a bleeding tendency in the course of a lifetime, defective wound healing, and habitual abortion.