InterPro domain: IPR033308

This entry includes mammalian PGAP5 protein (also known as MPPE1) and budding yeast Ted1 and Cdc1 proteins. PGAP5 is involved in transport of GPI-anchored proteins from the ER to the Golgi [ 1 ]. Ted1 is a GPI-glycan remodelase that acts together with Emp24 and Erv25 in cargo exit from the endoplasmic reticulum [ 2 , 3 ]. Ted1 functions as the yeast orthologue of mammalian PGAP5 by removing a specific EtNP on GPI-glycan. By contrast, the other yeast PGAP5 homologue, Cdc1, seems not to be involved in GPI-AP trafficking [ 4 ]. Instead, removes specifically the side-chain EtNP placed at the first mannose of the GPI-glycan, which is not important for trafficking but facilitates the integration of GPI-APs into the yeast cell wall [ 4 ].

1. GPI glycan remodeling by PGAP5 regulates transport of GPI-anchored proteins from the ER to the Golgi. Cell 139, 352-65
2. COPII coat composition is actively regulated by luminal cargo maturation. Curr. Biol. 25, 152-62
3. Identification of yeast proteins necessary for cell-surface function of a potassium channel. Proc. Natl. Acad. Sci. U.S.A. 104, 18079-84
4. Cdc1 removes the ethanolamine phosphate of the first mannose of GPI anchors and thereby facilitates the integration of GPI proteins into the yeast cell wall. Mol. Biol. Cell 25, 3375-88