Fig. 2

Biosynthetic pathways of mucin-type O-glycans. Glycosyltransferases involved in the synthesis are indicated. Additional modifications exist (not shown). B3GALT5 β1,3-galactosyltransferase 5, B3GNT β1,3-N-acetylglucosaminyltransferase; B4GALTs, β1,4-galactosyltransferases, C1GALT1, core 1 β1,3-galactosyltransferase, Fuc-T fucosyltransferase, GCNT β1,6-N-acetylglucosaminyltransferase, ST3Gal Gal: α2,3-sialyltransferase, ST6Gal-I Gal: α2,6-sialyltransferase-I, ST6GalNAc GalNAc: α2,6-sialyltransferase, ST6GlcNAc-I GlcNAc: α2,6-sialyltransferase-I, ppGALNTs UDPGalNAc-polypeptide N-acetylgalactosaminyltransferases, GalNAc N-acetylgalactosamine, GlcNAc N-acetylglucosamine, Gal galactose, NeuAc N-acetylneuraminic acid, Fuc fucose. Glycosyltransferases shown in Table 1 are highlighted, except B4GALNT3