4FZ0

Crystal structure of acid-sensing ion channel in complex with psalmotoxin 1 at low pH


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural plasticity and dynamic selectivity of acid-sensing ion channel-spider toxin complexes.

Baconguis, I.Gouaux, E.

(2012) Nature 489: 400-405

  • DOI: 10.1038/nature11375
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Acid-sensing ion channels (ASICs) are voltage-independent, amiloride-sensitive channels involved in diverse physiological processes ranging from nociception to taste. Despite the importance of ASICs in physiology, we know little about the mechanism o ...

    Acid-sensing ion channels (ASICs) are voltage-independent, amiloride-sensitive channels involved in diverse physiological processes ranging from nociception to taste. Despite the importance of ASICs in physiology, we know little about the mechanism of channel activation. Here we show that psalmotoxin activates non-selective and Na(+)-selective currents in chicken ASIC1a at pH 7.25 and 5.5, respectively. Crystal structures of ASIC1a-psalmotoxin complexes map the toxin binding site to the extracellular domain and show how toxin binding triggers an expansion of the extracellular vestibule and stabilization of the open channel pore. At pH 7.25 the pore is approximately 10 Å in diameter, whereas at pH 5.5 the pore is largely hydrophobic and elliptical in cross-section with dimensions of approximately 5 by 7 Å, consistent with a barrier mechanism for ion selectivity. These studies define mechanisms for activation of ASICs, illuminate the basis for dynamic ion selectivity and provide the blueprints for new therapeutic agents.


    Organizational Affiliation

    Vollum Institute, Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Acid-sensing ion channel 1
A, B, C
450Gallus gallusMutation(s): 0 
Gene Names: ASIC1 (ACCN2)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Other Ion Channels
Protein: 
ASIC1 Acid-Sensing Ion Channel (ΔASIC1; N- and C-term deletions)
Find proteins for Q1XA76 (Gallus gallus)
Go to Gene View: ASIC1
Go to UniProtKB:  Q1XA76
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Pi-theraphotoxin-Pc1a
M, N, O
40Psalmopoeus cambridgeiMutation(s): 0 
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Other Ion Channels
Protein: 
ASIC1 Acid-Sensing Ion Channel (ΔASIC1; N- and C-term deletions)
Find proteins for P60514 (Psalmopoeus cambridgei)
Go to UniProtKB:  P60514
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A, B, C
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
GOL
Query on GOL

Download SDF File 
Download CCD File 
C
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B, C
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.202 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 232.290α = 90.00
b = 108.710β = 119.78
c = 126.360γ = 90.00
Software Package:
Software NamePurpose
PHENIXrefinement
HKL-2000data reduction
PHASERphasing
HKL-2000data scaling
ADSCdata collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-08-01
    Type: Initial release
  • Version 1.1: 2012-10-03
    Type: Database references