Two canonical subunits of the 26S proteasome, Rpn10 and Rpn13 (AT2G26590) , function as ubiquitin (Ub) receptors. Drosophila 26S proteasome subunit Rpn10 Plays a major role in both the direct and indirect recognition of ubiquitinated substrates of ubiquitin/26S proteasome-mediated proteolysis (UPP) .
