Phosphatidylinositol-glycan biosynthesis class O protein (PIGO)

Phosphatidylinositol-glycan biosynthesis class O protein (PIGO) is an enzyme required for the biosynthesis of glycosylphosphatidylinositol (GPI) anchors, specifically catalyzing the transfer of ethanolamine phosphate to the third mannose residue in the GPI anchor’s glycan core[1][2][3][4]. This step is crucial for the subsequent attachment of proteins to the cell membrane via the GPI anchor, which is essential for the membrane localization and function of numerous proteins, including enzymes, adhesion molecules, and receptors[1][4][5]. PIGO is expressed in various tissues, and biallelic pathogenic variants result in a congenital disorder of glycosylation, commonly referred to as Mabry syndrome or hyperphosphatasia with impaired intellectual development syndrome 2. Clinical features include intellectual disability, elevated serum alkaline phosphatase, distinctive facial features, global developmental delay, seizures, congenital malformations, and, in some cases, gastrointestinal and bone abnormalities[2][3][4]. PIGO itself is not a direct therapeutic target for any approved drugs, but its deficiency is clinically relevant for diagnosis and genetic counseling.

Other names

GPI ethanolamine phosphate transferase 3, catalytic subunitGPI ethanolamine phosphate transferase 3Phosphatidylinositol glycan anchor biosynthesis, class OPIG-OHPMRS2Mabry syndrome geneFLJ00135DKFZp434M222PIGO_HUMAN