Recombinant Human PSME2 protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

PSME2 also known as PA28β or Proteasome Activator Subunit 2 is a regulatory protein with a molecular mass of approximately 28 kDa. It forms a part of the 11S regulator complex which modulates proteasome activities specifically the 20S proteasome. PSME2 is important in facilitating the degradation of endogenous proteins by opening the gate on the 20S proteasome core. It consistently expresses in various tissues with notable expression in immune-related tissues such as the spleen and thymus indicating its significant role in immune system functions.

Biological function summary

PSME2 participates in immunoproteasome formation impacting antigen processing and presentation. It binds to the 20S proteasome core facilitating a switch in proteolytic activities that enable the generation of peptide fragments suited for MHC class I molecule presentation. The biological function of PSME2 is critical in adaptive immune responses where it increases the efficiency and specificity of antigen processing. As part of the PA28 protein complex PSME2 partners with other subunits like PSME1 to enhance the degradation of oxidized proteins contributing to cellular homeostasis.

Pathways

Studies highlight PSME2’s involvement in the ubiquitin-proteasome pathway an important process for intracellular protein degradation. This pathway handles the removal of misfolded or damaged proteins and PSME2’s interaction with the 20S proteasome reflects its necessity for effective proteostasis. Additionally PSME2 acts in coordination with other proteasome subunits and cofactors such as PSME3 to modulate activity rates in response to cellular signals therefore integrating cellular responses to stress and damage repairs.

Researchers often link PSME2 to autoimmune diseases and cancer. In autoimmune conditions improper processing of antigens due to altered PSME2 function can lead to inappropriate immune responses with PSME2's altered expression observed in diseases like rheumatoid arthritis. With respect to cancer PSME2’s impact on antigen presentation affects tumor immune surveillance where reduced activity might allow immune evasion by cancer cells. Its relationship with the proteasome suggests connections with pathways involving proteins like β-catenin which play roles in disease progression and immune system evasion strategies.