Proteasome subunit beta type-1 (PSMB1) (PSMB1)

The Proteasome subunit beta type-1 (PSMB1) is a critical catalytic component of the 20S core particle of the 26S proteasome, a multi-protein complex responsible for the degradation of ubiquitinated proteins (Source: UniProt P20618). PSMB1 specifically exhibits peptidyl-glutamyl peptide-hydrolyzing (PGPH) or caspase-like activity, cleaving peptide bonds following acidic amino acid residues (Source: NCBI Gene ID: 5689). This subunit plays a vital role in maintaining cellular proteostasis by regulating the levels of proteins involved in the cell cycle, signal transduction, and apoptosis. In many cancers, particularly multiple myeloma and mantle cell lymphoma, proteasome activity is upregulated to cope with high protein synthesis rates and to suppress pro-apoptotic signals. Therapeutic agents such as bortezomib and carfilzomib target the catalytic subunits of the proteasome, including PSMB1, to induce proteotoxic stress and trigger programmed cell death in malignant cells (Source: DrugBank DB00188). While PSMB5 is often the primary target, the inhibition of PSMB1 contributes to the overall efficacy and helps overcome certain resistance mechanisms in proteasome-targeted therapies (Source: PubMed PMID: 22210321).

Other names

PSMB1Macropain subunit C2Multicatalytic endopeptidase complex subunit C2Proteasome component C220S proteasome subunit beta-1Proteasome subunit beta type-1

Inhibition of the peptidyl-glutamyl peptide-hydrolyzing (caspase-like) activity of the 20S proteasome through covalent or non-covalent binding to the catalytic N-terminal threonine residue (Source: PubMed PMID: 22210321).