Information AboutFactor V |
| CATEGORIES ABOUT FACTOR V | |
| coagulation system | |
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GENETICS The Gene for factor V is located on the first Chromosome (1q23). It is genomically related to the family of multicopper oxidases, and is homologous to coagulation factor VIII. The gene spans 70, consists of 25 exons, and the resulting protein has a relative molecular mass of approximately 330000. PHYSIOLOGY Factor V circulates in plasma as a single-chain molecule with a plasma half-life of about 12 hours. Half-lifes up to 36 hours have been reported, though. Factor V is able to bind to activated Platelet s and is activated by Thrombin . On activation, factor V is spliced in two chains (heavy and light chain with molecular masses of 110000 and 73000, respectively) which are nonconvalently bound to each other by Calcium . Factor Va, the activated form, is a Cofactor for Factor X in its reciprocal activation of prothrombin (factor II) into thrombin. Factor Va is degraded by Activated Protein C , one of the principal physiological inhibitors of coagulation. ROLE IN DISEASE Various hereditary disorders of factor V are known. Deficiency is associated with a rare mild form of fashion. Other Mutation s of factor V are associated with Venous Thrombosis . They are the most common hereditary causes for Thrombophilia (a tendency to form Blood Clot s). The most common one of these, Factor V Leiden , is due to the replacement of an Arginine residue with Glutamine at amino acid position 506 (R506Q). All prothrombotic factor V mutations (factor V Leiden, factor V Cambridge, factor V Hong Kong) make it resistant to cleavage by activated protein C ("APC resistance"). It therefore remains active and increases the rate of thrombin generation. HISTORY It was discovered in 1947 by Dr Paul Owren (1905-1990). The complete amino acid sequence of the protein was published in 1987 by Jenny ''et al''. REFERENCE
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