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PTGS1

Function

Dual cyclooxygenase and peroxidase in the biosynthesis pathway of prostanoids, a class of C20 oxylipins mainly derived from arachidonate, with a particular role in the inflammatory response. The cyclooxygenase activity oxygenates arachidonate (AA, C20:4(n-6)) to the hydroperoxy endoperoxide prostaglandin G2 (PGG2), and the peroxidase activity reduces PGG2 to the hydroxy endoperoxide PGH2, the precursor of all 2-series prostaglandins and thromboxanes. This complex transformation is initiated by abstraction of hydrogen at carbon 13 (with S-stereochemistry), followed by insertion of molecular O2 to form the endoperoxide bridge between carbon 9 and 11 that defines prostaglandins. The insertion of a second molecule of O2 (bis-oxygenase activity) yields a hydroperoxy group in PGG2 that is then reduced to PGH2 by two electrons (PubMed:7947975). Involved in the constitutive production of prostanoids in particular in the stomach and platelets. In gastric epithelial cells, it is a key step in the generation of prostaglandins, such as prostaglandin E2 (PGE2), which plays an important role in cytoprotection. In platelets, it is involved in the generation of thromboxane A2 (TXA2), which promotes platelet activation and aggregation, vasoconstriction and proliferation of vascular smooth muscle cells (Probable).

Pathway

Lipid metabolism; prostaglandin biosynthesis.

Sequence similarities

Belongs to the prostaglandin G/H synthase family.

Cellular localization

  • Microsome membrane
  • Peripheral membrane protein
  • Endoplasmic reticulum membrane
  • Peripheral membrane protein

Alternative names

  • Prostaglandin G/H synthase 1
  • Cyclooxygenase-1
  • Prostaglandin H2 synthase 1
  • Prostaglandin-endoperoxide synthase 1
  • COX-1
  • PGH synthase 1
  • PGHS-1
  • PHS 1
  • PTGS1
  • COX1

Target type

Proteins

Primary research area

Immunology & Infectious Disease

Other research areas

  • Cardiovascular
  • Immuno-oncology
  • Neuroscience

Molecular weight

68686Da