MG-132 (Ethanol Solution), proteasome inhibitor

Supplementary information

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

Cathepsin B is a cysteine protease playing an important role in protein degradation. It functions within lysosomes and it is also called CTSB. This enzyme has a molecular weight of approximately 28 kDa. Cathepsin B expression is primarily found in various cell types including macrophages and neutrophils. IKB alpha or nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha acts as a regulator of NF-kB signaling pathway preventing NF-kB transcription factor from entering the nucleus. Interferon beta often abbreviated as IFN-beta is a cytokine with a molecular weight about 22 kDa expressed mainly in immune cells. It plays roles in antiviral defense and immune regulation.

Biological function summary

Cathepsin B contributes to cellular remodeling apoptosis and antigen presentation. It is not part of any known stable multi-protein complexes. IKB alpha regulates immune responses by controlling the activation of NF-kB which is part of a larger complex inhibited by proteasome activity. Interferon beta influences the antiviral response through JAK-STAT pathway signaling enhancing the production of other antiviral proteins. The 20S proteasome subunits like C2/HC2 LMP2 LMP7 and alpha subunits (including PSMA5) in combination with C5 6 and 7 build the core particle responsible for degrading ubiquitinated proteins. HLA B7 presents antigens to T-cells forming part of the major histocompatibility complex class I.

Pathways

Cathepsin B motions within lysosomal degradation and apoptosis pathways. It is related to proteins like Bcl-2 in the apoptosis context contributing to autophagic processes. IKB alpha is fundamental within the NF-kB signaling pathway maintaining immune homeostasis by connecting with proteins such as IKK. Proteasome 20S components particularly LMP2 and LMP7 incorporate into the antigen processing pathway impacting antigen recognition related to the immunoproteasome. This framework aids HLA class I molecules like HLA B7 in triggering immune responses.

Cathepsin B is linked with cancer often upregulated in tumor cells aiding metastasis and angiogenesis. It associates with other lysosomal enzymes and matrix metalloproteinases. IKB alpha malfunctions may lead to chronic inflammation and autoimmune diseases connected through overactivated NF-kB pathways. Interferon beta is therapeutically significant for multiple sclerosis modulating immune activity along with proteins like IL-10. Deficiency or dysregulation within the proteasome pathway can contribute to ubiquitin-proteasome related disorders with the immunoproteasome playing roles in diseases such as rheumatoid arthritis by modifying antigenic peptide generation.