PSMB5 Antibody from MyBioSource.com

Description: The proteasome is a multicatalytic proteinase complex with a highly ordered ring-shaped 20S core structure. The core structure is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. This gene encodes a member of the proteasome B-type family, also known as the T1B family, that is a 20S core beta subunit in the proteasome. This catalytic subunit is not present in the immunoproteasome and is replaced by catalytic subunit 3i (proteasome beta 8 subunit). Multiple transcript variants encoding different isoforms have been found for this gene.
Function: Component of the 20S core proteasome complex involved in the proteolytic degradation of most intracellular proteins. This complex plays numerous essential roles within the cell by associating with different regulatory particles. Associated with two 19S regulatory particles, forms the 26S proteasome and thus participates in the ATP-dependent degradation of ubiquitinated proteins. The 26S proteasome plays a key role in the maintenance of protein homeostasis by removing misfolded or damaged proteins that could impair cellular functions, and by removing proteins whose functions are no longer required. Associated with the PA200 or PA28, the 20S proteasome mediates ubiquitin-independent protein degradation. This type of proteolysis is required in several pathways including spermatogenesis (20S-PA200 complex) or generation of a subset of MHC class I-presented antigenic peptides (20S-PA28 complex). Within the 20S core complex, PSMB5 displays a chymotrypsin-like activity.
Subunit Structure: The 26S proteasome consists of a 20S proteasome core and two 19S regulatory subunits. The 20S proteasome core is a barrel-shaped complex made of 28 subunits that are arranged in four stacked rings. The two outer rings are each formed by seven alpha subunits, and the two inner rings are formed by seven beta subunits. The proteolytic activity is exerted by three beta-subunits PSMB5, PSMB6 and PSMB7. Directly interacts with POMP (PubMed:15944226). Interacts with HIV-1 TAT protein (PubMed:14550573). Interacts with ABCB1 and TAP1 (PubMed:15488952).
Similarity: Belongs to the peptidase T1B family