Ubiquitin (Ub) is a highly conserved protein found ubiquitously in eukaryotic organisms. The conjugation of ubiquitin to proteins is an important means to regulate protein activity for many cellular processes by tagging them for degradation. Removal of Ub can rescue proteins from degradation. This is accomplished by the ubiquitin-specific processing protease (UBP) family of enzymes. Ubiquitin specific processing protease 11 (USP11) is a member of this family. USP11 has been found to associate with several proteins and may have functions independent of its deubiquitinating activity. USP11 deubiquitinates and associates with the RanGTP-binding protein, RanBPM. It has also been found to associate with BRCA2 and participate in the BRCA2 DNA damage related pathway; however, it does not appear to be involved in BRCA2 deubiquitination. USP11 also appears to play a role in the regulation of the IKKalpha and p53 signaling pathway by a mechanism independent of it deubiquitination activity.