Proteasome subunit alpha type-1 (PSMA1)

Proteasome subunit alpha type-1 (PSMA1) is an essential component of the 20S proteasome core complex, playing a structural and regulatory role in cellular protein degradation through the ubiquitin-proteasome pathway. As part of the multicatalytic complex, it contributes to forming the alpha-ring gating system that controls substrate entry into the internal proteolytic chamber. The 20S core, together with regulatory particles (such as 19S, 11S), mediates ATP-dependent and independent cleavage of polyubiquitinated, misfolded, or damaged proteins, thus ensuring cellular protein quality control, regulating cell cycle, apoptosis, and immune functions (particularly antigen presentation via MHC class I). PSMA1 has gained interest as a cancer target due to its overexpression and oncogenic roles in several solid tumors and hematologic malignancies, notably mediating cancer cell proliferation, migration, invasion, and resistance to therapy. Drugs targeting the proteasome, like bortezomib and carfilzomib, are used therapeutically in multiple myeloma and other cancers. However, inhibition of proteasome activity is associated with significant side effects and the emergence of therapeutic resistance. Elevated PSMA1 expression is associated with poor prognosis in cancers such as gastric and colon cancer, and its detection can serve as a biomarker for tumor burden.

Other names

Proteasome 20S subunit alpha 120S proteasome subunit alpha-6HC2NUPROS30PSC2PROS-30alpha-6MGC14542MGC14575MGC14751MGC1667MGC21459MGC22853MGC2391530 kDa prosomal proteinMacropain subunit C2Multicatalytic endopeptidase complex subunit C2Proteasome component C2Proteasome nu chainProteasome subunit alpha-6proteasome subunit α6HEL-S-275epididymis secretory protein Li 275macropain subunit nuprotein P30-33Ktesticular tissue protein Li 150

Inhibition of proteasomal protein degradation; Disruption of ubiquitin-proteasome pathway; Stabilization/accumulation of regulatory proteins (e.g., pro-apoptotic proteins, cell cycle proteins)