PSMD11 (D1T1R) Rabbit mAb #14303

The 26S proteasome is a highly abundant proteolytic complex involved in the degradation of ubiquitinated substrate proteins. It consists largely of two sub-complexes, the 20S catalytic core particle (CP) and the 19S/PA700 regulatory particle (RP) that can cap either end of the CP. The CP consists of two stacked heteroheptameric β-rings (β_1-7) that contain three catalytic β-subunits and are flanked on either side by two heteroheptameric α-rings (α_1-7). The RP includes a base and a lid, each having multiple subunits. The base, in part, is composed of a heterohexameric ring of ATPase subunits belonging to the AAA (ATPases Associated with diverse cellular Activities) family. The ATPase subunits function to unfold the substrate and open the gate formed by the α-subunits, thus exposing the unfolded substrate to the catalytic β-subunits. The lid consists of ubiquitin receptors and DUBs that function in recruitment of ubiquitinated substrates and modification of ubiquitin chain topology (1,2). Other modulators of proteasome activity, such as PA28/11S REG, can also bind to the end of the 20S CP and activate it (1,2).
Proteasome 26S subunit, non-ATPase, 11 (PSMD11, RPN6) is a non-ATPase subunit of the 19S/PA700 RP lid subcomplex. Research studies have shown that PSMD11 expression is regulated by FOXO4 in human embryonic stem cells (hESCs). Increased PSMD11 expression in hESCs correlates with high levels of proteasome activity, which may be required for protection from proteotoxic stress and senescence (3).