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PubMed · 9438374

Factor V.

J Rosing·G Tans
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Abstract

Factor V is a single chain glycoprotein that plays an essential role in the regulation of blood coagulation. After initiation of coagulation, factor V is converted into factor Va through limited proteolysis. Factor Va acts as protein cofactor in the prothrombin-activating complex, which is comprised of the serine protease factor Xa, Ca2+ ions and a procoagulant membrane surface. Factor Va accelerates factor Xa-catalysed conversion of prothrombin into thrombin more than 10(4)-fold. The cofactor activity of factor Va in prothrombin activation is down-regulated by activated protein C (APC). The physiological importance of this regulatory pathway is demonstrated by the occurrence of hereditary thrombophilia in individuals with a genetic defect that makes factor Va less sensitive to proteolytic inactivation by APC (APC resistance).

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Blood CoagulationFactor VFactor VaHumansProthrombinThrombinJournal ArticleReview

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BibTeXRIS

J Rosing, G Tans. 1997. Factor V.. https://doi.org/10.1016/s1357-2725(97)00040-x

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