The proteasome is a multicatalytic proteinase complex which is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. The proteasome has an ATP-dependent proteolytic activity. The 26S proteasome consists of a 20S proteasome core and two 19S regulatory subunits. The 20S proteasome core is composed of 28 subunits that are arranged in four stacked rings, resulting in a barrel-shaped structure. The two end rings are each formed by seven alpha subunits, and the two central rings are each formed by seven beta subunits. The catalytic chamber with the active sites is on the inside of the barrel. Belongs to the peptidase T1A family. Note: This description may include information from UniProtKB.
Protein type: Proteasome complex; Protease; EC 18.104.22.168
Biological Process: positive regulation of ubiquitin-protein ligase activity during mitotic cell cycle; negative regulation of ubiquitin-protein ligase activity during mitotic cell cycle; protein polyubiquitination; viral reproduction; apoptosis; antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent; DNA damage response, signal transduction by p53 class mediator resulting in cell cycle arrest; activation of NF-kappaB transcription factor; regulation of apoptosis; antigen processing and presentation of peptide antigen via MHC class I; regulation of ubiquitin-protein ligase activity during mitotic cell cycle; proteolysis involved in cellular protein catabolic process; anaphase-promoting complex-dependent proteasomal ubiquitin-dependent protein catabolic process; regulation of inflammatory response; antigen processing and presentation of exogenous peptide antigen via MHC class I; gene expression; mitotic cell cycle; regulation of amino acid metabolic process; G1/S transition of mitotic cell cycle; negative regulation of apoptosis
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.