Factor XII

Title: Factor XII
CAS Registry Number: 9001-30-3
CAS Name: Blood-coagulation factor XII
Additional Names: Hageman factor; HF
Literature References: Mol wt about 82,000. An enzyme which circulates in zymogen form in blood and when activated initiates the first of a series of events in coagulation of blood plasma. Enzymatic nature of blood coagulation is described by the "cascade" theory in which clotting factors interact with one another in a stepwise manner, one acting as an enzyme, the other as substrate, in a sequence of reactions leading to the formation of thrombin, q.v.: Davie, Ratnoff, Science 145, 1310 (1964); MacFarlane, Nature 202, 498 (1964). Factor XII initiates clotting when blood or plasma comes into contact with glass, collagen, or surface-active agents. Once activated, it interacts with factor XI, q.v., to convert it to an enzyme. Factor XII is a sialoglycoprotein with esterase activity. Its activation by glass may be viewed as a dynamic alteration of the tertiary structure of the protein moiety: Schoenmakers et al., Biochim. Biophys. Acta 101, 166 (1965). Isoln of human and rabbit factor XII in zymogen form: C. G. Cochrane, K. D. Wuepper, J. Exp. Med. 134, 986 (1971); H. Saito et al., Circ. Res. 34, 641 (1974). Highly purified Hageman factor undergoes a change in physical properties during activation: Donaldson, Ratnoff, Science 150, 754 (1965). Factor XII deficiency is termed the Hageman trait. Unlike deficiencies in all other clotting factors, persons with Hageman trait do not show significant bleeding tendencies. Reviews: Ratnoff in New Blood Clotting Factors, I. S. Wright et al., Eds. (Schattauer-Verlag, Stuttgart, 1960) pp 116-122; Ratnoff et al., in Thrombolytic Activity and Related Phenomena, I. S. Wright et al., Eds. (Schattauer-Verlag, Stuttgart, 1961) pp 364-378; several authors in Recent Advances in Blood Coagulation, L. Poller, Ed. (J. & A. Churchill, London, 1969); J. Spragg, K. F. Austen, Compr. Immunol. 3, 125-143 (1977); J. H. Griffin, C. G. Cochrane, Methods Enzymol. 45B, 56-65 (1976).
Properties: Sedimentation coefficient, s°20,w = 7.08. Diffusion constant, D°20,w = 7.14 ´ 10-7 cm2/sec. uv max at pH 7: 280 nm (E1%1cm 12.0). Isoelectric pt pH 8.0.
Absorption maximum: uv max at pH 7: 280 nm (E1%1cm 12.0)
Factor XIII Fadrozole Fagarine Famoxadone Famphur

Coagulation factor XII (Hageman factor)
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols F12 (; HAE3; HAEX; HAF)
External IDs OMIM: 610619 MGI: 1891012 HomoloGene: 425 ChEMBL: 2821 GeneCards: F12 Gene
EC number
RNA expression pattern
PBB GE F12 205774 at tn.png
More reference expression data
Species Human Mouse
Entrez 2161 58992
Ensembl ENSG00000131187 ENSMUSG00000021492
UniProt P00748 Q80YC5
RefSeq (mRNA) NM_000505 NM_021489
RefSeq (protein) NP_000496 NP_067464
Location (UCSC) Chr 5:
176.83 – 176.84 Mb
Chr 13:
55.42 – 55.43 Mb
PubMed search [1] [2]

Coagulation factor XII, also known as Hageman factor, is a plasma protein. It is the zymogen form of factor XIIa, an enzyme (EC of the serine protease (or serine endopeptidase) class. In humans, factor XII is encoded by the F12 gene.[1]