TBXAS1
Function
Catalyzes the conversion of prostaglandin H2 (PGH2) to thromboxane A2 (TXA2), a potent inducer of blood vessel constriction and platelet aggregation (PubMed:11097184, PubMed:11297515, PubMed:22735388, PubMed:24009185, PubMed:8436233, PubMed:9873013). Cleaves also PGH2 to 12-hydroxy-heptadecatrienoicacid (12-HHT) and malondialdehyde, which is known to act as a mediator of DNA damage. 12-HHT and malondialdehyde are formed stoichiometrically in the same amounts as TXA2 (PubMed:11297515, PubMed:22735388, PubMed:9873013). Additionally, displays dehydratase activity, toward (15S)-hydroperoxy-(5Z,8Z,11Z,13E)-eicosatetraenoate (15(S)-HPETE) producing 15-KETE and 15-HETE (PubMed:17459323).
Involvement in disease
Ghosal hematodiaphyseal dysplasia
GHDD
Rare autosomal recessive disorder characterized by increased bone density with predominant diaphyseal involvement and aregenerative corticosteroid-sensitive anemia. Aregenerative anemia is characterized by bone marrow failure, so that functional marrow cells are regenerated slowly or not at all.
None
The disease is caused by variants affecting the gene represented in this entry.
Thromboxane synthetase deficiency has been detected in some patients with a bleeding disorder due to platelet dysfunction.
Pathway
Lipid metabolism; fatty acid metabolism.
Sequence Similarities
Belongs to the cytochrome P450 family.
Tissue Specificity
Platelets, lung, kidney, spleen, macrophages and lung fibroblasts.
Cellular localization
- Endoplasmic reticulum membrane
- Multi-pass membrane protein
Alternative names
CYP5, CYP5A1, TXAS, TBXAS1, Thromboxane-A synthase, TXA synthase, TXS, Cytochrome P450 5A1, Hydroperoxy icosatetraenoate dehydratase