The Discovery of Novel Experimental Therapies for Inflammatory Arthritis

Figure 5

The Proteasome Signaling Pathway. Normally produced (left) or misfolded (right) proteins that are destined for 28S proteasome-mediated degradation are targeted for degradation either by phosphorylation (P) or after tagging with ubiquitin (Ub), via ubiquitin ligase [133]. In this pathway, a polyubiquitin protein chain becomes bound to the 28S proteasome providing a mechanism required for protein degradation. Nonphosphorylated or non-Ub-tagged proteins (i.e., “activated proteins”) can bypass the proteasome pathway and be transported to the nucleus.