Component of the 26S proteasome, a multiprotein complex involved in the ATP-dependent degradation of ubiquitinated proteins (   , ). This complex plays a key role in the maintenance of protein homeostasis by removing misfolded or damaged proteins, which could impair cellular functions, and by removing proteins whose functions are no longer required (   , ). Therefore, the proteasome participates in numerous cellular processes, including cell cycle progression, apoptosis, or DNA damage repair (   , ). Within the complex, functions as a proteasomal ubiquitin receptor . Engages and activates 19S-associated deubiquitinases UCHL5 and PSMD14 during protein degradation ( , ). UCHL5 reversibly associate with the 19S regulatory particle whereas PSMD14 is an intrinsic subunit of the proteasome lid subcomplex ( , ).
Subcellular locations: Cytoplasm, Nucleus