Description
Product Usage Information
Western Blotting: 1:1000
Storage
Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/mL BSA, 50% glycerol, and less than 0.02% sodium azide. Store at -20°C. Do not aliquot the antibody.
Protocol
Available protocols: Western Blotting
Specificity / Sensitivity
PSMB9/LMP2 (E7J1L) Rabbit Monoclonal Antibody recognizes endogenous levels of total PSMB9/LMP2 protein. This antibody does not cross-react with PSMB6/Y protein.
Species Reactivity: Human, Mouse, Rat
Source / Purification
Monoclonal antibody is produced by immunizing animals with a synthetic peptide corresponding to residues near the carboxy terminus of human PSMB9/LMP2 protein.
Background
The 20S proteasome is the major proteolytic enzyme complex involved in intracellular protein degradation. It consists of four stacked rings, each with seven distinct subunits. The two outer layers are identical rings composed of α subunits (called PSMAs), and the two inner layers are identical rings composed of β subunits. While the catalytic sites are located on the β rings (1-3), the α subunits are important for assembly and as binding sites for regulatory proteins (4). Seven different α and ten different β proteasome genes have been identified in mammals (5). PA700, PA28, and PA200 are three major protein complexes that function as activators of the 20S proteasome. PA700 binds polyubiquitin with high affinity and associates with the 20S proteasome to form the 26S proteasome, which preferentially degrades polyubiquitinated proteins (1-3). The proteasome has a broad substrate spectrum that includes cell cycle regulators, signaling molecules, tumor suppressors, and transcription factors. By controlling the degradation of these intracellular proteins, the proteasome functions in cell cycle regulation, cancer development, immune responses, protein folding, and disease progression (6-9).~Proteasome subunit β type-9 (PSMB9, LMP2) is expressed as a proenzyme that is autocleaved to form a mature immunoproteasome core particle subunit (10). Like other immunoproteasome subunits, PSMB9/LMP2 expression is induced by IFN-γ and subsequent replacement of constitutively expressed PSMB6/Y within the 20S proteasome proteolytic core particle facilitates processing and presentation of MHC class I-restricted peptide antigens on the cell surface (11-13). Research studies have shown that immunoproteasome subunits, including PSMB9/LMP2, are overexpressed in some types of human cancers and expression levels correlate with survival and improved response to immune-checkpoint blockade (14).
Alternate Names
beta1i; large multifunctional peptidase 2; LMP2; Low molecular mass protein 2; Macropain chain 7; MGC70470; Multicatalytic endopeptidase complex chain 7; PRAAS3; proteasome (prosome, macropain) subunit, beta type, 9 (large multifunctional peptidase 2); proteasome 20S subunit beta 9; proteasome catalytic subunit 1i; Proteasome chain 7; proteasome subunit beta 6i; proteasome subunit beta 9; Proteasome subunit beta type-9; Proteasome subunit beta-1i; proteasome subunit beta1i; proteasome-related gene 2; PSB9; PSMB6i; PSMB9; Really interesting new gene 12 protein; RING12
