Glycophosphatidylinositol anchor

Overbaugh, J., Miller, A. and Eiden, M. (2001) Receptors and entry cofactors for retroviruses include single and multiple transmembrane-spanning proteins as well as newly described glycophosphatidylinositol-anchored and secreted proteins. Microbio. Mol. Biol. Reviews55, 371-389. 

Kim J, Surewicz K, Gambetti P et al (2009) The role of glycophosphatidylinositol anchor in the amplification of the scrapie isoform of prion protein in vitro. FEBS Lett 583 3671-3675... 

The mannose-rich glycophosphatidylinositol anchor compound of Trypanosoma brucei (18) has been prepared bonded to appropriate phospholipids. ... 

R. Chen, E. I. Walter, G. Parker, J. P. Lapurga, J. L. Millan, Y. Ikehara, S. Udenfriend M. E. Medof. Mammalian glycophosphatidylinositol anchor transfer to proteins and posttransfer deacylation. Proc Natl Acad Sci USA, 1998, 95, 9512-9517. 

A. Puoti A. Conzelmann. Structural characterization of free glycolipids which are potential precursors for glycophosphatidylinositol anchors in mouse thymoma cell lines. J Biol Chem, 1992, 267, 22673-22680. 

Figure 6 Structure of a GPI anchor. Glycophosphatidylinositol (GPI) anchors are important functional structures on the cell surface. The fatty add phosphatidylinositol is embedded in the exterior leaflet plasma membrane and features a tether consisting of a specific series of monosaccharides and phosphoethanolamine linked to the C-terminus of a protein.

The discovery that phospholipase C could release alkahne phosphatase from lipid-linked structures on cellular surfaces (39) led to the identification of the glycophosphatidylinositol (GPI) membrane component (40). GPI structures are a synthetic tour de force of nature, combining lipids, carbohydrates, and proteins into a single macromolecule. Certain proteins require GPI anchoring to be functional for example, Ly-6A/E-mediated T-cell activation is critically dependent on its GPI anchor (41), and folate uptake functions efficiently only when its receptors are GPI anchored (42). 

Roberts, C, Madsen, R, Fraser-Reid, B, Studies related to synthesis of glycophosphatidylinositol membrane-bound protein anchors. 5. n-Pentenyl ortho esters for mannan components, J. Am. Chem. Soc., 117, 1546-1553, 1995. 

FIG. 2. Common features of glycophosphatidylinositol (GPIs) anchors of glycoproteins. Characteristic sites of chemical and enzymatic reactions of GPIs are shown. EtN, 2-aminoethanol (ethanolamine). 

Redman, C. A., Green, B. N., Thomas-Oates, J. E. and Reinhold, V. N. (1994) Analysis of glycophosphatidylinositol membrane anchors by electrospray ionisation-mass spectrometry and collision induced dissociation. Glycoconjugate J.,, 187-93. 

P. Moran I. W. Caras. Fusion of sequence elements from non-anchored proteins to generate a fully functional signal for glycophosphatidylinositol membrane anchor attachment. J Cell Biol, 1991, 115, 1595-1600. 

---