Glycosylphosphatidylinositol (GPI) Anchors: Biochemistry and Cell Biology: Introduction to a Thematic Review Series

Glycosylphosphatidylinositol (GPI) is a lipid anchor for many cell-surface proteins. The GPI anchor represents a posttranslational modification of proteins with a glycolipid and is used ubiquitously in eukaryotes and most likely in some Archaea, but not in Eubacteria. GPI-anchored proteins are the major form of cell-surface proteins in protozoa. In fungi, many GPI-anchored proteins are ultimately incorporated into the cell wall. In humans, there are at least 150 GPI-anchored proteins, and they may function in a variety of roles serving as receptors, adhesion molecules, enzymes, transcytotic receptors and transporters, and protease inhibitors.