Ceramide glucosyltransferase (UGCG, CGT, GCS) catalyzes the first glycosylation step in glycosphingolipid biosynthesis by transferring glucose to ceramide (Ichikawa et al. 1996). UGCG is localized on the cytosolic part of the cis-Golgi membrane. The cytosolic PLEKHA8 (FAPP2) will transport the product GlcCer to the plasma membrane. GlcCer is also transported to the inside of the Golgi membrane by MDR1 ("flipping"; Fabiana de Rosa et al., 2004; Eckford & Sharom, 2005; reviewed by Liu & Li, 2013).