Phosphatidylinositol glycan anchor biosynthesis class W protein (PIGW)

Phosphatidylinositol glycan anchor biosynthesis class W protein (PIGW) is an inositol acyltransferase enzyme localized in the endoplasmic reticulum, crucial for a key step in glycosylphosphatidylinositol (GPI) anchor biosynthesis[1][2][3][4]. PIGW catalyzes the transfer of a fatty acid from an acyl-CoA donor to the inositol ring of the GPI biosynthetic intermediate, glucosaminyl-phosphatidylinositol (GlcN-PI), enabling proper assembly and subsequent remodeling of GPI anchors, which tether many proteins to the cell surface[1][2][3][4]. Defects in PIGW lead to human diseases such as hyperphosphatasia with mental retardation syndrome type 5 (HPMRS5), a congenital disorder characterized by cognitive impairment, seizures, and biochemical abnormalities such as elevated alkaline phosphatase[1][3]. PIGW is essential for the cell surface expression of GPI-anchored proteins, and loss of this activity has broad cellular and clinical consequences[1][4].

Other names

Glucosaminyl-phosphatidylinositol-acyltransferase PIGWPIGWGlcN-PI-acyltransferasePIG-WGwt1FLJ37433HPMRS5GPI-anchored wall protein transfer 1 homolog (S. cerevisiae)