1p9d
High-resolution structure of the complex of HHR23A ubiquitin-like domain and the C-terminal ubiquitin-interacting motif of proteasome subunit S5a
OverviewOverview
HHR23A, a protein implicated in nucleotide excision repair, belongs to a class of proteins containing both a ubiquitin-like (Ubl) domain and one or more ubiquitin-associated (UBA) domains, suggesting a role in the ubiquitin-proteasome pathway as well. The Ubl domain binds with high affinity to the second ubiquitin-interacting motif (UIM) of the S5a subunit of the proteasome. Here we present the solution structures of the HHR23A Ubl domain, the second UIM of S5a (UIM-2), and the Ubl:S5a-UIM-2 complex. The HHR23A Ubl domain is structurally similar to ubiquitin. The S5a UIM forms an alpha-helix with an unexpected hairpin loop that contributes to the binding interface with Ubl. The molecular determinants of the Ubl-proteasome interaction are revealed by analysis of the structures, chemical shift mapping, mutant binding studies and sequence conservation.
About this StructureAbout this Structure
1P9D is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
Structural determinants for the binding of ubiquitin-like domains to the proteasome., Mueller TD, Feigon J, EMBO J. 2003 Sep 15;22(18):4634-45. PMID:12970176 Page seeded by OCA on Sat May 3 04:50:53 2008