Additional info: |
Prostaglandin E Synthase (PGE Synthase) catalyzes the isomerization of PGH2 to PGE2. Cytosolic and microsomal PGE synthase enzymes have been cloned and characterized. Cytosolic PGE synthase (cPGE synthase) is a glutathione-dependent enzyme with a predicted size of 18.6 kDa (23 kDa on SDS-PAGE). The enzyme is expressed in a wide variety of tissues and cells, the levels of which are unaffected by treatment with IL-1.beta. and TNF.alpha.. However, enzyme expression increases approximately 3-fold in rat brain following LPS treatment. Microsomal PGE synthase is a 16 kDa protein expressed in a variety of tissues including prostate, testes, and small intestine, as well as in A549 and HeLa cells. In contrast to cPGE synthase, mPGE synthase protein expression is increased in A549 cells following treatment with IL-1.beta.. The two enzymes show <10% homology at the amino acid level. |