Figure 2.

An overview of Notch signaling. The steps requiring ubiquitination are highlighted. In the absence of activation, Notch is internalized and degraded in the lysosomes. DSL ligands activity depends on trafficking and ubiquitination. Upon ligand binding, Notch extracellular domain is transendocytosed into the ligand-expressing cell, and the remaining receptor undergoes proteolytic cleavages as well as ubiquitination and deubiquitination to become a transcription factor.