26S proteasome non-ATPase regulatory subunit 12 (PSMD12)

26S proteasome non-ATPase regulatory subunit 12 (PSMD12) is a non-ATPase component of the 19S regulator (lid subcomplex) of the 26S proteasome, a large multisubunit protease complex essential for ATP-dependent degradation of ubiquitinated proteins in eukaryotic cells. PSMD12 is required for proper assembly and function of the proteasome, facilitating recognition, deubiquitination, and delivery of target proteins into the 20S catalytic core for proteolysis. It plays a vital role in protein homeostasis, cell cycle, apoptosis, and the generation of antigenic peptides for immune surveillance. Disruption of PSMD12 function (e.g., by haploinsufficient mutations) is linked to intellectual disability, autism spectrum disorder, and related neurodevelopmental syndromes. There are currently no drugs that selectively target PSMD12; most proteasome inhibitors act on the core particle rather than regulatory subunits.

Other names

p55Rpn5STISS26S proteasome regulatory subunit RPN526S proteasome regulatory subunit p55proteasome (prosome, macropain) 26S subunit, non-ATPase, 12

(not directly targeted by current drugs; most proteasome inhibitors act on the catalytic 20S core, not on PSMD12 or other non-ATPase regulatory subunits)