phosphatidylinositol

noun
phos·​phat·​i·​dyl·​ino·​si·​tol | \ ˈfäs-fə-ˌtī-dᵊl-i-ˈnō-sə-ˌtȯl, fäs-ˌfa-tə-dᵊl-, -ī-ˈnō-, -ˌtōl How to pronounce phosphatidylinositol (audio) \

Medical Definition of phosphatidylinositol

: an acidic phospholipid that contains an inositol attached to the phosphate group of phosphatidic acid and is found especially in cell membranes where it is precursor to several substances that mediate cellular activity as second messengers The parent phospholipid, phosphatidylinositol, can modulate the activity of several membrane-bound enzymes, including sodium-potassium adenosine triphosphatase, and mediate transmembrane signaling processes.— Bruce J. Holub, The New England Journal of Medicine, 7 May 1992