This entry includes proteasome subunit beta type-8 (PSMB8), also known as subunit beta-5i, a component found only in the immunoproteasome, a specialist version of the proteasome that generates antigenic peptides for display on the major histocompatibility complex. The three catalytically active beta subunits of the normal proteasome are replaced by three gamma interferon-induced subunits, all of which are also catalytically active. PSMB8 replaces subunit PSMB5 []. A mutation in this subunit is the cause of autoinflammation and lipodystrophy [].