3NS8

Crystal structure of an open conformation of Lys48-linked diubiquitin at pH 7.5


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.707 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.186 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural and biochemical studies of the open state of Lys48-linked diubiquitin.

Lai, M.Y.Zhang, D.Laronde-Leblanc, N.Fushman, D.

(2012) Biochim.Biophys.Acta 1823: 2046-2056

  • DOI: 10.1016/j.bbamcr.2012.04.003

  • PubMed Abstract: 
  • Ubiquitin (Ub) is a small protein highly conserved among eukaryotes and involved in practically all aspects of eukaryotic cell biology. Polymeric chains assembled from covalently-linked Ub monomers function as molecular signals in the regulation of a ...

    Ubiquitin (Ub) is a small protein highly conserved among eukaryotes and involved in practically all aspects of eukaryotic cell biology. Polymeric chains assembled from covalently-linked Ub monomers function as molecular signals in the regulation of a host of cellular processes. Our previous studies have shown that the predominant state of Lys48-linked di- and tetra-Ub chains at near-physiological conditions is a closed conformation, in which the Ub-Ub interface is formed by the hydrophobic surface residues of the adjacent Ub units. Because these very residues are involved in (poly)Ub interactions with the majority of Ub-binding proteins, their sequestration at the Ub-Ub interface renders the closed conformation of polyUb binding incompetent. Thus the existence of open conformation(s) and the interdomain motions opening and closing the Ub-Ub interface is critical for the recognition of Lys48-linked polyUb by its receptors. Knowledge of the conformational properties of a polyUb signal is essential for our understanding of its specific recognition by various Ub-receptors. Despite their functional importance, open states of Lys48-linked chains are poorly characterized. Here we report a crystal structure of the open state of Lys48-linked di-Ub. Moreover, using NMR, we examined interactions of the open state of this chain (at pH4.5) with a Lys48-linkage-selective receptor, the UBA2 domain of a shuttle protein hHR23a. Our results show that di-Ub binds UBA2 in the same mode and with comparable affinity as the closed state. Our data suggest a mechanism for polyUb signal recognition, whereby Ub-binding proteins select specific conformations out of the available ensemble of polyUb chain conformations. This article is part of a Special Issue entitled: Ubiquitin Drug Discovery and Diagnostics.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ubiquitin
A, B
76Homo sapiensMutation(s): 0 
Gene Names: UBC
Find proteins for P0CG48 (Homo sapiens)
Go to Gene View: UBC
Go to UniProtKB:  P0CG48
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EPE
Query on EPE

Download SDF File 
Download CCD File 
B
4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID
HEPES
C8 H18 N2 O4 S
JKMHFZQWWAIEOD-UHFFFAOYSA-N
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.707 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.186 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 24.047α = 90.00
b = 56.498β = 93.37
c = 46.841γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
ADSCdata collection
MOLREPphasing
PHENIXrefinement
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-07-20
    Type: Initial release
  • Version 1.1: 2012-10-10
    Type: Database references
  • Version 1.2: 2012-10-17
    Type: Database references