Abstract 2421 Chain Branching by the NEDD4 Family Ubiquitin Ligases Stimulates Protein Degradation

The NEDD4 family of ubiquitin ligases targets a multitude of protein substrates for ubiquitination and degradation by the proteasome. However, most in vitro studies indicate that the NEDD4 family E3s have a preference for forming K63-linked chains, which typically are not associated with proteasomal degradation in vivo. We aimed to address this discrepancy by examining the architecture of ubiquitin chains formed by the NEDD4 family E3s and evaluating the ability of different chain types to support proteasomal degradation in vitro.