Proteasome subunit beta type-3 (PSMB3)

Proteasome subunit beta type-3 (PSMB3) is a non-catalytic subunit of the 20S core proteasome complex, an essential multi-protein structure responsible for ATP/ubiquitin-dependent proteolysis of intracellular proteins and thus maintaining protein homeostasis[1][2][3][4]. The proteasome complex consists of four stacked rings, with PSMB3 located within one of the seven-membered beta rings. It is broadly expressed in eukaryotic cells and plays a key role in removing misfolded, damaged, or regulatory proteins, antigen processing for MHC class I molecules, and is implicated in spermatogenesis and several regulatory pathways. Dysregulation of PSMB3, or mutations affecting proteasome function, are associated with cancer, neurodegenerative diseases, and potentially hereditary disorders involving protein aggregation or defective proteolysis[1][2][3][4]. In certain cancer contexts, PSMB3 expression or splicing patterns may have diagnostic or prognostic value[3]. No direct small-molecule inhibitors specifically targeting PSMB3 alone have been validated in clinical use. Most clinically relevant inhibitors target the 20S proteasome core as a whole, not individual beta subunits[2][3].

Other names

Proteasome 20S subunit beta 3Proteasome subunit beta-3Proteasome chain 13Proteasome component C10-IIProteasome theta chainHC10-IIMGC4147Epididymis secretory sperm binding proteinProteasome (prosome, macropain) subunit beta type 3

Proteasome inhibition (blocks proteolytic degradation; accumulation of ubiquitinated proteins; induces apoptosis, especially in rapidly dividing cancer cells)