[1] GPI is composed of a phosphatidylinositol group linked through a carbohydrate-containing linker (glucosamine and mannose glycosidically bound to the inositol residue) and via an ethanolamine phosphate (EtNP) bridge to the C-terminal amino acid of a mature protein.
[citation needed] Phospholipase C (PLC) is an enzyme known to cleave the phospho-glycerol bond found in GPI-anchored proteins.
The T-cell marker Thy-1 and acetylcholinesterase, as well as both intestinal and placental alkaline phosphatases, are known to be GPI-linked and are released by treatment with PLC.
GPI-linked proteins are thought to be preferentially located in lipid rafts, suggesting a high level of organization within plasma membrane microdomains.
[citation needed] The variable surface glycoproteins from the sleeping sickness protozoan Trypanosoma brucei are attached to the plasma membrane via a GPI anchor.