Biosynthesis of glycosyl phosphatidylinositol protein anchors

Glycosyl phosphatidylinositols (GPIs) serve as membrane anchors for many plasma membrane proteins in all eukaryotic cells. African trypanosomes provide an ideal system for investigating GPIs, because these parasites produce extremely large quantities to anchor their major surface protein, the variant surface glycoprotein. Through radiolabeling methods and use of a cell-free system, the major features of the trypanosome GPI biosynthetic pathway have been elucidated. It is likely that these techniques, successful in the study of trypanosome GPIs, will be applicable to other eukaryotic cells.