2QKS

Crystal structure of a Kir3.1-prokaryotic Kir channel chimera


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.231 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structure of a Kir3.1-prokaryotic Kir channel chimera.

Nishida, M.Cadene, M.Chait, B.T.Mackinnon, R.

(2007) Embo J. 26: 4005-4015

  • DOI: 10.1038/sj.emboj.7601828

  • PubMed Abstract: 
  • The Kir3.1 K(+) channel participates in heart rate control and neuronal excitability through G-protein and lipid signaling pathways. Expression in Escherichia coli has been achieved by replacing three fourths of the transmembrane pore with the pore o ...

    The Kir3.1 K(+) channel participates in heart rate control and neuronal excitability through G-protein and lipid signaling pathways. Expression in Escherichia coli has been achieved by replacing three fourths of the transmembrane pore with the pore of a prokaryotic Kir channel, leaving the cytoplasmic pore and membrane interfacial regions of Kir3.1 origin. Two structures were determined at 2.2 A. The selectivity filter is identical to the Streptomyces lividans K(+) channel within error of measurement (r.m.s.d.<0.2 A), suggesting that K(+) selectivity requires extreme conservation of three-dimensional structure. Multiple K(+) ions reside within the pore and help to explain voltage-dependent Mg(2+) and polyamine blockade and strong rectification. Two constrictions, at the inner helix bundle and at the apex of the cytoplasmic pore, may function as gates: in one structure the apex is open and in the other, it is closed. Gating of the apex is mediated by rigid-body movements of the cytoplasmic pore subunits. Phosphatidylinositol 4,5-biphosphate-interacting residues suggest a possible mechanism by which the signaling lipid regulates the cytoplasmic pore.


    Organizational Affiliation

    Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, Rockefeller University, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Kir3.1-prokaryotic Kir channel chimera
A, B
321Mus musculusParaburkholderia xenovorans (strain LB400)
This entity is chimeric
Mutation(s): 1 
Gene Names: Kcnj3 (Girk1),
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
Kir3.1-Prokaryotic Kir Chimera
Find proteins for P63250 (Mus musculus)
Go to UniProtKB:  P63250
Find proteins for Q146M9 (Paraburkholderia xenovorans (strain LB400))
Go to UniProtKB:  Q146M9
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
A, B
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
BNG
Query on BNG

Download SDF File 
Download CCD File 
A
B-NONYLGLUCOSIDE
C15 H30 O6
QFAPUKLCALRPLH-UXXRCYHCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.256 
  • R-Value Work: 0.231 
  • Space Group: P 4
Unit Cell:
Length (Å)Angle (°)
a = 98.416α = 90.00
b = 98.416β = 90.00
c = 92.624γ = 90.00
Software Package:
Software NamePurpose
PDB_EXTRACTdata extraction
HKL-2000data reduction
MOLREPphasing
HKL-2000data collection
CNSrefinement
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-08-28
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2011-11-16
    Type: Atomic model
  • Version 1.3: 2017-06-07
    Type: Database references, Other, Source and taxonomy