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Activated protein C cleaves factor Va to factor Vi intermediate form

Stable Identifier
Homo sapiens
factor Va -> factor Vi
Locations in the PathwayBrowser

Activated protein C cleaves peptide bonds in activated factor V (factor Va), converting it to an inactive form (factor Vi). APC proteolysis involves cleavage of the factor Va heavy chain at Arg-334 (306 if signal peptide is not included) and Arg-534 (506 with no signal peptide) (Nicolaes et al. 1985). Most factor Va molecules are initially cleaved at Arg-534, yielding a partially active intermediate, followed by complete inactivation through cleavage at Arg-334 (Kalafatis et al. 1994). Factor Xa inhibits Arg-534 cleavage but this effect is mitigated by Protein S (Norstrom et al. 2006). A mutation of the APC cleavage sites in Fv at Arg-534Gln a.k.a. FVLeiden is the most common identifiable hereditary risk factor for venous thrombosis among Caucasians (Camire 2011).

Literature References
PubMed ID Title Journal Year
2538457 The roles of protein C and thrombomodulin in the regulation of blood coagulation J Biol Chem 1989
Participant Of
Catalyst Activity
Catalyst Activity
serine-type endopeptidase activity of Activated protein C:Protein S [plasma membrane]
Physical Entity
Orthologous Events