Fibrinstabilisierender Faktor
genetisch codiertes Protein, Enzym, Gerinnungsfaktor
Factor XIII or fibrin stabilizing factor is an enzyme (Vorlage:EC number) of the blood coagulation system that crosslinks fibrin. When thrombin has converted fibrinogen to fibrin, the latter forms a proteinaceous network in which every E-unit is crosslinked to only one D-unit. Factor XIII is activated by thrombin into factor XIIIa; its activation into Factor XIIIa requires calcium as a cofactor.
It is also known as Laki-Lorand factor. It has a long half life, ranging from 5-9 days.
Enzyme
Factor XIII consists of twice two subunits (2 A and 2 B), the genes for which are on different chromosomes:
- A subunit (6p25-p24). The transglutaminase part; this adds an alkyl group to the nitrogen on a glutamine residue, which binds in turn with a lysine on the other chain.
- B subunit (1q31-q32.1). This has no clear enzymatic activity, and may serve as a carrier for the A subunit.
Role in disease
Factor XIII deficiency may occur very rarely, and can cause a severe bleeding tendency.
See also
External links
- Fibrinstabilisierender Faktor. In: Online Mendelian Inheritance in Man. (englisch) (A subunit) and Fibrinstabilisierender Faktor. In: Online Mendelian Inheritance in Man. (englisch) (B subunit)
- Factor XIII deficiency