Asymmetric lipid distribution is a fundamental characteristic of biological lipid bilayers, one such axample is the translocation of the Man5GlcNAc2-PP-Dol intermediate from the cytosolic side of the ER membrane to the lumen before the completion of the biosynthesis of Glc3Man9GlcNAc2-PP-Dol []. RFT1 encodes an evolutionarily conserved protein required for this translocation.
