Predicted to enable enzyme regulator activity. Predicted to be involved in proteasome-mediated ubiquitin-dependent protein catabolic process. Predicted to be located in membrane. Predicted to be part of proteasome regulatory particle, base subcomplex. Predicted to be active in nucleus and proteasome storage granule. Is expressed in head. Orthologous to human PSMD1 (proteasome 26S subunit, non-ATPase 1).