Factor V

Title: Factor V
CAS Registry Number: 9001-24-5
CAS Name: Blood-coagulation factor V
Additional Names: proaccelerin; labile factor; accelerator globulin
Trademarks: Ac-globulin
Literature References: Mol wt above 300,000. Participates in the later stages of blood coagulation. Activated by factor X, q.v., and along with Ca2+ and phospholipid forms a complex which converts prothrombin to thrombin, q.q.v. Accelerates the interaction of prothrombin, thromboplastin and Ca2+ ions: Ware, Seegers, Fed. Proc. 7, 131 (1948). Thrombin produces serum Ac-globulin, accelerin, a far more potent accelerator, from plasma Ac-globulin, apparently by catalytic action: Ware et al., Science 106, 618 (1947); Rapaport et al., Blood 21, 221 (1963). Purification: Ware, Seegers, J. Biol. Chem. 172, 699 (1948); Blombäck, Blombäck, Nature 198, 886 (1963). Role in the scheme of blood coagulation: Pavlovsky in Fibrinogen and Fibrin Turnover of Clotting Factors, R. B. Hunter et al., Eds. (Schattauer-Verlag, Stuttgart, 1963) pp 443-454. Proaccelerin deficiency is characterized by prolonged Quick's prothrombin time, and cephalin time, abnormal thromboplastin generation test, abnormal prothrombin consumption, and prolonged whole blood clotting time: Owren in Thrombolytic Activity and Related Phenomena, I. S. Wright et al., Eds. (Schattauer-Verlag, Stuttgart, 1961) pp 387-391. Review: R. W. Colman, Prog. Hemostasis Thromb. 3, 109-143 (1976). Purification, stability, amino acid composition, physical properties of bovine and human factor V: R. W. Colman, R. M. Weinberg, Methods Enzymol. 45B, 107-122 (1976).
Factor VII Factor VIII Factor X Factor XI Factor XII

Coagulation factor V (proaccelerin, labile factor)

PDB rendering based on 1czs.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols F5 (; FVL; PCCF; RPRGL1; THPH2)
External IDs OMIM: 612309 MGI: 88382 HomoloGene: 104 ChEMBL: 3618 GeneCards: F5 Gene
RNA expression pattern
PBB GE F5 204714 s at tn.png
PBB GE F5 204713 s at tn.png
More reference expression data
Species Human Mouse
Entrez 2153 14067
Ensembl ENSG00000198734 ENSMUSG00000026579
UniProt P12259 O88783
RefSeq (mRNA) NM_000130 NM_007976
RefSeq (protein) NP_000121 NP_032002
Location (UCSC) Chr 1:
169.48 – 169.56 Mb
Chr 1:
164.15 – 164.22 Mb
PubMed search [1] [2]

Factor V (pronounced factor five) is a protein of the coagulation system, rarely referred to as proaccelerin or labile factor. In contrast to most other coagulation factors, it is not enzymatically active but functions as a cofactor. Deficiency leads to predisposition for hemorrhage, while some mutations (most notably factor V Leiden) predispose for thrombosis.