Structure of hRpn13 Pru with the 14-residue intrinsically disordered region at the extreme C-terminal end of hRpn2 that is used to recruit Rpn13 to the proteasome. The classic pleckstrin homology fold of hRpn13 Pru (periwinkle blue) is displayed as both a ribbon and surface diagram with hRpn2 (940-953) (light orange) as a stick model with nitrogen and oxygen atoms displayed in blue and red, respectively. The ubiquitin binding regions on hRpn13 Pru are colored yellow. (X. Lu et al. Nat Commun. 2017 8, 15540.)