PMID: 20739285

Authors:

Riedinger C, Boehringer J, Trempe JF, Lowe ED, Brown NR, Gehring K, Noble ME, Gordon C, Endicott JA

Title:

The structure of RPN10 and its interactions with polyubiquitin chains and the proteasome subunit RPN12.

Journal:

J Biol Chem. 2010 Aug 24.

Abstract:

Schizosaccharomyces pombe Rpn10 (SpRpn10) is a proteasomal ubiquitin (Ub) receptor located within the 19S regulatory particle where it binds to subunits of both the base and lid sub-particles. We have solved the structure of full-length SpRpn10 by determining the crystal structure of the VWA domain and characterising the full-length protein by NMR. We demonstrate that the single Ub interacting motif (UIM) of SpRpn10 forms a 1:1 complex with K48-linked diUb, which it binds selectively over monoUb and K63-linked diUb. We further show that the SpRpn10 UIM binds to SpRpn12, a subunit of the lid sub-particle, with an affinity comparable to Lys48-linked diUb. This is the first observation of a UIM binding other than a Ub fold and suggests that SpRpn12 could modulate the activity of SpRpn10 as a proteasomal Ub receptor.