Proaccelerin
| Proaccelerin | ||
|---|---|---|
|
||
| after 1czs | ||
| Properties of human protein | ||
| Mass / length primary structure | 1360 = 709 + 651 amino acids | |
| Identifier | ||
| Gene names | F5 ; FVL; PCCF; factor V | |
| External IDs | ||
| Occurrence | ||
| Homology family | Factor V | |
| Parent taxon | Euteleostomi | |
| Orthologue | ||
| human | House mouse | |
| Entrez | 2153 | 14067 |
| Ensemble | ENSG00000198734 | ENSMUSG00000026579 |
| UniProt | P12259 | O88783 |
| Refseq (mRNA) | NM_000130 | NM_007976 |
| Refseq (protein) | NP_000121 | NP_032002 |
| Gene locus | Chr 1: 169.51 - 169.59 Mb | Chr 1: 164.15 - 164.22 Mb |
| PubMed search | 2153 |
14067
|
Proaccelerin (also Proaccelerin or Factor V ) is a protein involved in blood clotting . In contrast to the other coagulation factors , it has no enzymatic function, but only serves as a cofactor . The protein has a molecular mass of 251,671 Daltons (Da) and belongs to the group of α-globulins . Its plasma concentration is approx. 10 mg / l, synthesis probably takes place in the liver .
genetics
The gene for proaccelerin is on the first chromosome (1q23).
physiology
Proaccelerin circulates in plasma and has a half-life of about 12 hours. It is activated by thrombin by splitting it into two chains, a “heavy” (molecular weight 110 kDa) and a “light” (molecular weight 73 kDa), which are not covalently bound to each other by calcium .
The activated form of proaccelerin, also called accelerin or factor Va (formerly factor VI), is a cofactor of the Stuart-Prower factor (factor X), which converts prothrombin (factor II) into thrombin .
Factor Va is broken down by the activated protein C through proteolysis and thus rendered ineffective. This is one of the most important natural inhibition mechanisms for blood clotting.
The function of Proaccelerin or its activation for factor Va is shown in the flow chart “The coagulation cascade” , abbreviated as “ V ” there.
Diseases
There are various hereditary diseases that are based on a malfunction of the Proaccelerin. Proaccelerin deficiency causes a rare, mild form of hemophilia called parahemophilia or Owren's syndrome. This occurs with an incidence of 1: 1,000,000 and is inherited as an autosomal recessive trait .
Other mutations in proaccelerin cause venous thrombosis . They are the most common cause of inherited thrombophilia (increased blood clot formation). In the most common factor V Leiden mutation, the amino acid arginine in position 506 has been replaced by glutamine (R506Q). All prothrombotic proaccelerin mutations ( factor V Leiden mutation , factor V Cambridge mutation, factor V Hong Kong mutation) cause the accelerator to be resistant to cleavage by activated protein C (so-called APC resistance ) . Therefore, it remains active and increases the formation of thrombi .
Research history
Proaccelerin was discovered in 1947 by Paul Owren (1905–1990). The complete amino acid sequence was published in 1987 by Jenny et al. released.
Individual evidence
- ^ GA Nicolaes, B. Dahlbäck: Factor V and thrombotic disease: description of a janus-faced protein . In: Arterioscler. Thromb. Vasc. Biol. Vol. 22, No. 4 , April 2002, p. 530-538 , PMID 11950687 (English).
- ↑ K. Segers, B. Dahlbäck, GA Nicolaes: Coagulation factor V and thrombophilia: background and mechanisms . In: Thromb. Haemost. Vol. 98, No. 3 , September 2007, pp. 530-542 , PMID 17849041 (English).
- ↑ RJ Jenny, DD Pittman, JJ Toole, RW Kriz, RA Aldape, RM Hewick, RJ Kaufman, KG man: Complete cDNA and derived amino acid sequence of human factor V . In: Proceedings of the National Academy of Sciences . tape 84 , no. 14 , 1987, pp. 4846-4850 , PMID 3110773 (English, pnas.org [PDF]).
Web links
- Proaccelerin. In: Online Mendelian Inheritance in Man . (English)