The Structure of Rpn10 and its Interactions with Polyubiquitin Chains and the Proteasome Subunit Rpn12.
Riedinger, C., Boehringer, J., Trempe, J.F., Lowe, E.D., Brown, N.R., Gehring, K., Noble, M.E., Gordon, C., Endicott, J.A.(2010) J Biol Chem 285: 33992
- PubMed: 20739285 
- DOI: https://doi.org/10.1074/jbc.M110.134510
- Primary Citation of Related Structures:  
2X5N - PubMed Abstract: 
Schizosaccharomyces pombe Rpn10 (SpRpn10) is a proteasomal ubiquitin (Ub) receptor located within the 19 S regulatory particle where it binds to subunits of both the base and lid subparticles. We have solved the structure of full-length SpRpn10 by determining the crystal structure of the von Willebrand factor type A domain and characterizing the full-length protein by NMR. We demonstrate that the single Ub-interacting motif (UIM) of SpRpn10 forms a 1:1 complex with Lys(48)-linked diUb, which it binds selectively over monoUb and Lys(63)-linked diUb. We further show that the SpRpn10 UIM binds to SpRpn12, a subunit of the lid subparticle, with an affinity comparable with Lys(48)-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.
Organizational Affiliation: 
Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.