Component of the 20S core proteasome complex involved in theproteolytic degradation of most intracellular proteins. This complexplays numerous essential roles within the cell by associating withdifferent regulatory particles. Associated with two 19S regulatoryparticles, forms the 26S proteasome and thus participates in the ATP-dependent degradation of ubiquitinated proteins. The 26S proteasomeplays a key role in the maintenance of protein homeostasis by removingmisfolded or damaged proteins that could impair cellular functions, andby removing proteins whose functions are no longer required. Associatedwith the PA200 or PA28, the 20S proteasome mediates ubiquitin-independent protein degradation. This type of proteolysis is requiredin several pathways including spermatogenesis (20S-PA200 complex) orgeneration of a subset of MHC class I-presented antigenic peptides (20S-PA28 complex). Inhibits the transactivation function of HIF-1Aunder both normoxic and hypoxia-mimicking conditions. The interactionwith EMAP2 increases the proteasome-mediated HIF-1A degradation underthe hypoxic conditions. Plays a role in hepatitis C virus internalribosome entry site-mediated translation. Mediates nucleartranslocation of the androgen receptor (AR) and thereby enhancesandrogen-mediated transactivation. Promotes MAVS degradation andthereby negatively regulates MAVS-mediated innate immune response. [1-8]

MSYDRAITVFSPDGHLFQVEYAQEAVKKGSTAVGVRGRDIVVLGVEKKSVAKLQDERTVRKICALDDNVCMAFAGLTADARIVINRARVECQSHRLTVEDPVTVEYITRYIASLKQRYTQSNGRRPFGISALIVGFDFDGTPRLYQTDPSGTYHAWKANAIGRGAKSVREFLEKNYTDEAIETDDLTIKLVIKALLEVVQSGGKNIELAVMRRDQSLKILNPEEIEKYVAEIEKEKEENEKKKQKKAS