Enzymes Involved in the Biosynthesis of GPI-Anchored Proteins

Abstract

Glycosylphosphatidylinositol (GPI) is a glycolipid utilized for post-translational modification of proteins in eukaryotes and plays a role in anchoring modified proteins to the cell membrane. In yeast, there are over 60 kinds, and in humans, more than 150 kinds of diverse GPI-anchored proteins (GPI-APs) exist. GPI is biosynthesized from phosphatidylinositol (PI) on the endoplasmic reticulum membrane, and after being attached to a protein, the GPI-APs are transported to the cell surface via the Golgi apparatus. In mammalian cells, the biosynthesis of GPI-APs requires more than 20 steps, and it has been revealed that over 30 genes are involved. This review outlines the biosynthesis of mammalian GPI-APs and the enzymes involved, and introduces recent findings.

graphical abstract