3RQU

Crystal structure of a prokaryotic pentameric ligand-gated ion channel, ELIC


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.089 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.209 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the pentameric ligand-gated ion channel ELIC cocrystallized with its competitive antagonist acetylcholine.

Pan, J.Chen, Q.Willenbring, D.Yoshida, K.Tillman, T.Kashlan, O.B.Cohen, A.Kong, X.P.Xu, Y.Tang, P.

(2012) Nat Commun 3: 714-714

  • DOI: 10.1038/ncomms1703
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • ELIC, the pentameric ligand-gated ion channel from Erwinia chrysanthemi, is a prototype for Cys-loop receptors. Here we show that acetylcholine is a competitive antagonist for ELIC. We determine the acetylcholine-ELIC cocrystal structure to a 2.9-Å r ...

    ELIC, the pentameric ligand-gated ion channel from Erwinia chrysanthemi, is a prototype for Cys-loop receptors. Here we show that acetylcholine is a competitive antagonist for ELIC. We determine the acetylcholine-ELIC cocrystal structure to a 2.9-Å resolution and find that acetylcholine binding to an aromatic cage at the subunit interface induces a significant contraction of loop C and other structural rearrangements in the extracellular domain. The side chain of the pore-lining residue F247 reorients and the pore size consequently enlarges, but the channel remains closed. We attribute the inability of acetylcholine to activate ELIC primarily to weak cation-π and electrostatic interactions in the pocket, because an acetylcholine derivative with a simple quaternary-to-tertiary ammonium substitution activates the channel. This study presents a compelling case for understanding the structural underpinning of the functional relationship between agonism and competitive antagonism in the Cys-loop receptors, providing a new framework for developing novel therapeutic drugs.


    Organizational Affiliation

    Department of Anesthesiology, 2057 Biomedical Science Tower 3, 3501 Fifth Avenue, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ELIC Pentameric Ligand Gated Ion Channel from Erwinia Chrysanthemi
A, B, C, D, E, F, G, H, I, J
322Dickeya dadantii (strain 3937)Mutation(s): 0 
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Cys-Loop Receptor Family
Protein: 
Prokaryotic pentameric ligand-gated ion channel (ELIC)
Find proteins for E0SJQ4 (Dickeya dadantii (strain 3937))
Go to UniProtKB:  E0SJQ4
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H, I, J
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
MES
Query on MES

Download SDF File 
Download CCD File 
A, B, C, D, G, I
2-(N-MORPHOLINO)-ETHANESULFONIC ACID
C6 H13 N O4 S
SXGZJKUKBWWHRA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.089 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.209 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 105.289α = 90.00
b = 266.970β = 107.53
c = 111.074γ = 90.00
Software Package:
Software NamePurpose
PHENIXmodel building
SSRLdata collection
PHENIXrefinement
XDSdata reduction
PHENIXphasing
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-03-07
    Type: Initial release
  • Version 1.1: 2012-03-14
    Type: Database references, Other, Structure summary
  • Version 1.2: 2012-03-28
    Type: Database references