Abstract
Notch is a key signaling protein mediating cell-fate decisions during development. In this issue, Acar et al. (2008) describe a new gene called rumi that is required for Notch signaling in Drosophila. This gene encodes an O-glucosyltransferase that attaches glucose sugars to serine residues in the multiple EGF domains of the extracellular region of Notch. This modification by Rumi likely influences Notch folding and trafficking.
