Glycosylation of Specific Notch EGF Repeats by O-Fut1 and Fringe Regulates Notch Signaling in Drosophila

Cell Rep. 2019 Nov 12;29(7):2054-2066.e6. doi: 10.1016/j.celrep.2019.10.027.


Fringe glycosyltransferases differentially modulate the binding of Notch receptors to Delta/DLL versus Serrate/Jagged ligands by adding GlcNAc to O-linked fucose on Notch epidermal growth factor-like (EGF) repeats. Although Notch has 22 O-fucosylation sites, the biologically relevant sites affecting Notch activity during animal development in vivo in the presence or absence of Fringe are not known. Using a variety of assays, we find important roles in Drosophila Notch signaling for GlcNAc-fucose-O glycans on three sites: EGF8, EGF9, and EGF12. O-Fucose monosaccharide on EGF12 (in the absence of Fringe) is essential for Delta-mediated lateral inhibition in embryos. However, wing vein development depends on the addition of GlcNAc to EGF8 and EGF12 by Fringe, with a minor contribution from EGF9. Fringe modifications of EGF8 and EGF12 together prevent Notch from cis-inhibiting Serrate, thereby promoting normal wing margin formation. Our work shows the combinatorial and context-dependent roles of GlcNAc-fucose-O glycans on these sites in Drosophila Notch-ligand interactions.

Keywords: Drosophila; Pofut1; cis-inhibition; fringe; glycosylation; notch signaling.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster
  • Fucosyltransferases / genetics
  • Fucosyltransferases / metabolism*
  • Glycosylation
  • N-Acetylglucosaminyltransferases / genetics
  • N-Acetylglucosaminyltransferases / metabolism*
  • Receptors, Notch / genetics
  • Receptors, Notch / metabolism*
  • Repetitive Sequences, Amino Acid


  • Drosophila Proteins
  • N protein, Drosophila
  • Receptors, Notch
  • Fucosyltransferases
  • N-Acetylglucosaminyltransferases
  • O-fucosyltransferase 1, Drosophila
  • fng protein, Drosophila