Anti-proteasome 20S subunit beta 4 antibodies are used for the immunodetection of the protein encoded by the PSMB4 gene. In humans, the canonical protein has a reported length of 264 amino acid residues and a mass of 29.2 kDa. Its subcellular localization is in the nucleus and cytoplasm. A member of the Peptidase T1B protein family, it is reported to be a non-catalytic component of the 20S core proteasome complex involved in the proteolytic degradation of most intracellular proteins. The gene encoding this protein is implicated in Proteasome-associated autoinflammatory syndrome. Other names for this target antigen include HsN3, PRAAS3, PROS-26, PROS26, proteasome subunit beta type-4, 26 kDa prosomal protein, hsBPROS26, and HN3. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.