Involved in glycosylphosphatidylinositol-anchor biosynthesis. Transfers ethanolamine phosphate to the GPI third mannose which links the GPI-anchor to the C-terminus of the proteins by an amide bond. Involved in cell wall biosynthesis. Glycolipid biosynthesis; glycosylphosphatidylinositol-anchor biosynthesis. Glycosylated. Present with 300 molecules/cell in log phase SD medium. Belongs to the PIGG/PIGN/PIGO family. PIGO subfamily.