The glycosphingolipids (GSL) form part of eukaryotic cell membranes. They consist of a hydrophilic carbohydrate moiety linked to a hydrophobic ceramide tail embedded within the lipid bilayer of the membrane. Lactosylceramide, Gal1,4Glc1Cer (LacCer), is the common synthetic precursor to the majority of GSL found in vertebrates. Alpha 1.4-glycosyltransferases utilize UDP donors and transfer the sugar to a beta-linked acceptor. This region appears to be confined to higher eukaryotes. No function has been yet assigned to this region.