Glc,GlcNAc-Fuc-Pre-NOTCH Glc,Fuc-Pre-NOTCH Glycosylation of Pre-NOTCH by FRINGE Authored: Egan, SE, Orlic-Milacic, M, 2011-11-14 EC Number: 2.4.1.222 Edited: D'Eustachio, P, 2012-02-06 Edited: Orlic-Milacic, M, 2012-02-10 Pubmed10935626 Pubmed10935637 Pubmed21097675 Pubmed9187150 Pubmed9207795 Reactome Database ID Release 431912355 Reactome, http://www.reactome.org ReactomeREACT_118594 Reviewed: Haw, R, 2012-02-06 The Fringe family of glycosyl transferases in mammals includes LFNG (lunatic fringe), MFNG (manic fringe) and RFNG (radical fringe). Fringe enzymes function in the Golgi apparatus where they initiate the elongation of O linked fucose on fucosylated peptides by the addition of a beta 1,3 N acetylglucosaminyl group (Moloney et al. 2000). Fringe enzymes (LFNG, MNFG and RFNG) elongate conserved O fucosyl residues conjugated to EGF repeats of NOTCH, resulting in formation of disaccharide chains on NOTCH (GlcNAc beta1,3 fucitol). Fringe enzymes modulate NOTCH activity (Cohen et al. 1997, Johnston et al. 1997) by decreasing the affinity of NOTCH extracellular domain for JAG ligands (Brückner et al. 2000). In developing mouse thymocytes, Lfng enhances Notch1 activation by Dll4, resulting in prolonged Notch1 signaling that promotes self-renewal of TCR-beta-expressing progenitors (Yuan et al. 2011). Since the exact preference, if any, of fringe enzymes for NOTCH O fucose sites is not known, the extension of an O fucosyl residue at an unknown position is shown.