In contrast to the prevailing model for the internalization of ubiquitinated proteins, Hawryluk et al. (1) and Barriere et al. (2) demonstrate that high affinity interactions between polymeric or oligomeric ubiquitin and tandemly arranged UIM (ubiquitin-interacting motifs) of endocytic adaptors, which are localized to clathrin coated pits, function to mediate the internalization of ubiquitinated cargo. These two studies argue against monoubiquitinated cargo being internalized via caveolae. An accompanying commentary discusses how these results relate to the existing literature (3).
Journal
Traffic