InterPro domain: IPR023352

This domain is found in a widespread superfamily known as MAPEG (Membrane Associated Proteins in Eicosanoid and Glutathione metabolism) [ 1 ]. Included in this superfamily are:

• 5-lipoxygenase activating protein (gene FLAP), which seems to be required for the activation of 5-lipoxygenase.
• Leukotriene C4 synthase ( 2.5.1.37 ), which catalyses the production of LTC4 from LTA4.
• Microsomal glutathione S-transferase II ( 2.5.1.18 ) (GST-II), which also produces LTC4 from LTA4.
• Prostaglandin E synthase, which catalyses the synthesis of PGE2 from PGH2 (produced by cyclooxygenase from arachidonic acid).

The structure of this domain consists of four transmembrane helices [ 2 ].

1. Common structural features of MAPEG -- a widespread superfamily of membrane associated proteins with highly divergent functions in eicosanoid and glutathione metabolism. Protein Sci. 8, 689-92
2. Crystal structure of inhibitor-bound human 5-lipoxygenase-activating protein. Science 317, 510-2