Glc,Gal-GlcNAc-Fuc-Pre-NOTCH Glc,Sia-Gal-GlcNAc-Fuc-Pre-NOTCH Sialylation of Pre-NOTCH Authored: Egan, SE, Orlic-Milacic, M, 2011-11-14 EC Number: 2.4.99.4 Edited: D'Eustachio, P, 2012-02-06 Edited: Orlic-Milacic, M, 2012-02-10 Mature fringe-modified NOTCH usually has a tetrasaccharide attached to conserved fucosylated serine and threonine residues in EGF repeats. The chemical structure of these tetrasaccharides is Sia-alpha2,3-Gal-beta1,4-GlcNAc-beta1,3-fucitol (Moloney et al. 2000). The identity of sialyltransferase(s) that add sialic acid to galactose remains unknown in this context. Based on the type of chemical bonds in the tetrasaccharide, there are three known Golgi membrane sialyltransferases that could perform this function: ST3GAL3, ST3GAL4, ST3GAL6 (Harduin-Lepers et al. 2001). Pubmed10935626 Pubmed11530204 Reactome Database ID Release 431912378 Reactome, http://www.reactome.org ReactomeREACT_118739 Reviewed: Haw, R, 2012-02-06