Regulator of Notch signaling, a signaling pathway involved in cell-cell communications that regulates a broad spectrum of cell-fate determinations. Mainly acts as a positive regulator of Notch, but it may also act as a negative regulator, depending on the developmental and cell context. Mediates the antineural activity of Notch. May function as a ubiquitin ligase protein in the Notch pathway. S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)-ubiquitinyl-[acceptor protein]-L-lysine. Protein modification; protein ubiquitination. Homomultimer; the oligomerization is required for its function. Interacts with the ankyrin repeats of Notch. Ubiquitous. Expressed at low levels throughout embryogenesis and in larvae. The WWE domains are thought to mediate some protein-protein interaction, and are frequently found in ubiquitin ligases. Belongs to the Deltex family.