2NXX

Crystal Structure of the Ligand-Binding Domains of the T.castaneum (Coleoptera) Heterodimer EcrUSP Bound to Ponasterone A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.75 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.249 
  • R-Value Observed: 0.249 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural and functional characterization of a novel type of ligand-independent RXR-USP receptor.

Iwema, T.Billas, I.M.Beck, Y.Bonneton, F.Nierengarten, H.Chaumot, A.Richards, G.Laudet, V.Moras, D.

(2007) EMBO J 26: 3770-3782

  • DOI: 10.1038/sj.emboj.7601810
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Retinoid X receptor (RXR) and Ultraspiracle (USP) play a central role as ubiquitous heterodimerization partners of many nuclear receptors. While it has long been accepted that a wide range of ligands can activate vertebrate/mollusc RXRs, the existenc ...

    Retinoid X receptor (RXR) and Ultraspiracle (USP) play a central role as ubiquitous heterodimerization partners of many nuclear receptors. While it has long been accepted that a wide range of ligands can activate vertebrate/mollusc RXRs, the existence and necessity of specific endogenous ligands activating RXR-USP in vivo is still matter of intense debate. Here we report the existence of a novel type of RXR-USP with a ligand-independent functional conformation. Our studies involved Tribolium USP (TcUSP) as representative of most arthropod RXR-USPs, with high sequence homology to vertebrate/mollusc RXRs. The crystal structure of the ligand-binding domain of TcUSP was solved in the context of the functional heterodimer with the ecdysone receptor (EcR). While EcR exhibits a canonical ligand-bound conformation, USP adopts an original apo structure. Our functional data demonstrate that TcUSP is a constitutively silent partner of EcR, and that none of the RXR ligands can bind and activate TcUSP. These findings together with a phylogenetic analysis suggest that RXR-USPs have undergone remarkable functional shifts during evolution and give insight into receptor-ligand binding evolution and dynamics.


    Organizational Affiliation

    IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), UMR7104 CNRS, U596 INSERM, ULP, Département de Biologie et de Génomique Structurales, Illkirch, France.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Ecdysone Receptor (EcR, NRH1)
E, F, G, H
248Tribolium castaneumMutation(s): 0 
Gene Names: Ecdysone Receptor (EcR)ecr-a
Find proteins for A1JUG3 (Tribolium castaneum)
Go to UniProtKB:  A1JUG3

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Ultraspiracle (USP, NR2B4)
A, B, C, D
235Tribolium castaneumMutation(s): 0 
Gene Names: Ultraspiracle (USP)usp
Find proteins for A1JUG2 (Tribolium castaneum)
Go to UniProtKB:  A1JUG2
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
P1A
Query on P1A

Download CCD File 
E, F, G, H
2,3,14,20,22-PENTAHYDROXYCHOLEST-7-EN-6-ONE
C27 H44 O6
PJYYBCXMCWDUAZ-JJJZTNILSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.75 Å
  • R-Value Free: 0.281 
  • R-Value Work: 0.249 
  • R-Value Observed: 0.249 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 77.54α = 90
b = 89.628β = 91.97
c = 160.247γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
PDB_EXTRACTdata extraction
ADSCdata collection
HKL-2000data reduction
AMoREphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-10-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-10-18
    Changes: Refinement description