Glycosyl phosphatidylinositol phospholipase

There are also membrane proteins with extended P-chains through the bilayer, and channel proteins with their hydrophilic inner opening must also contain polar amino acid residues within the lipid bilayer. There is also a group of membrane proteins that are covalently bonded to bilayer lipids, including the glycosyl-phosphatidylinositol anchor [6]. These proteins are exposed on the membrane surface via a spacer arm consisting of an oligoglycan, and specific phospholipases can release the protein. 

Fig. 6.1 Scheme representing the structure and hydrolysis of glycosyl-phosphatidylinositol (GPI) (adapted from Refs. [1] and [7]). Free GPI and GPI-anchored proteins are represented, showing their similarity in structure. The points for phospholipase C (PLC) and phospholipase D (PLD) hydrolysis are indicated. The glycan component of free GPI is... 

G. Muller, E.A. Dearey, A. Korndor-EER, and W. Bandlow, Stimulation of a glycosyl-phosphatidylinositol-specific phospholipase by insulin and the sulfonylurea, glimepiride, in rat adipocytes depends on increased glucose transport, J. Cell. Biol., 1994, 126, 1267-1276. 

S. Movahedi and N. Hooper, Insulin stimulates the release of the glycosyl phosphatidylinositol-anchored membrane dipeptidase from 3T3-L1 adipocytes through the action of a phospholipase C, Biochem. J., 1997, 326, 531-537. 

Wong, YW, Low, MG. Phospholipase resistance of the glycosyl-phosphatidylinositol membrane anchor on human alkaline phosphatase. Clin Chem 1992 38 2517-2525. 

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