Figure 1.

Metabolic pathways and structure of glycosphingolipids, including gangliosides

Cer, ceramide; GalNAc-T, N-acetylgalactosaminyltransferase I (B4galnt1, GA2/GM2/GD2/GT2 synthase); GalT-I, galactosyltransferase I (B4galt6, lactosylceramide synthase); GalT-II, galactosyltransferase II (B3galt4, GA1/GM1/GD1b/GT1c synthase); GalT-III, galactosyltransferase III (Ugt8a, galactosylceramide synthase); GlcT, glucosyltransferase (Ugcg, glucosylceramide synthase); ST-I, sialyltransferase I (St3gal5, GM3/GM4 synthase); ST-II, sialyltransferase II (St8Sia1, GD3 synthase); ST-III, sialyltransferase III (St8Sia3, GT3 synthase); ST-IV, sialyltransferase IV (St3gal2, GM1b/GD1a/GT1b/GQ1c synthase); ST-V, sialyltransferase V (St8sia5, GD1c/GT1a/GQ1b/GP1c synthase); ST-VII, sialyltransferase VII (St6galnac6, GD1aα/GT1aα/GQ1bα/GP1cα synthase). Official symbols of genes are represented in italics in this legend. GM1, GD1a, GD1b, and GT1b are the most abundant ganglioside species in adult mammalian brain and neurons.