MSI_000061580

PIP(18:0/20:4(6Z,8E,10E,14Z)-2OH(5S,12R)) is an oxidized phosphatidylinositol phosphate (PIP). As other PIPs, oxidized phosphatidylinositol phosphates are acidic (anionic) phospholipids that consist of a phosphatidic acid backbone, linked via the phosphate group to a phosphorylated inositol (hexahydroxycyclohexane). Phosphatidylinositol phosphates are generated from phosphatidylinositols, which are phosphorylated by a number of different kinases that place the phosphate moiety on positions 4 and 5 of the inositol ring, although position 3 can also be phosphorylated. Phosphatidylinositol phosphates can have many different combinations of fatty acids of varying lengths and saturation attached at the C-1 and C-2 positions. PIP(18:0/20:4(6Z,8E,10E,14Z)-2OH(5S,12R)), in particular, consists of one chain of octadecanoyl at the C-1 position and one chain of Leukotriene B4 at the C-2 position. The most important phosphatidylinositol phosphate in both quantitative and biological terms is phosphatidylinositol 4-phosphate. Phosphatidylinositol and the phosphatidylinositol phosphates are the main source of diacylglycerols that serve as signaling molecules, via the action of phospholipase C enzymes. Phosphatidylinositol phosphates are usually present at low levels only in tissues, typically at about 1 to 3\\% of the concentration of phosphatidylinositol.