3UM7

Crystal structure of the human two pore domain K+ ion channel TRAAK (K2P4.1)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.31 Å
  • R-Value Free: 0.323 
  • R-Value Work: 0.317 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Crystal structure of the human K2P TRAAK, a lipid- and mechano-sensitive K+ ion channel.

Brohawn, S.G.del Marmol, J.MacKinnon, R.

(2012) Science 335: 436-441

  • DOI: 10.1126/science.1213808

  • PubMed Abstract: 
  • TRAAK channels, members of the two-pore domain K(+) (potassium ion) channel family K2P, are expressed almost exclusively in the nervous system and control the resting membrane potential. Their gating is sensitive to polyunsaturated fatty acids, mecha ...

    TRAAK channels, members of the two-pore domain K(+) (potassium ion) channel family K2P, are expressed almost exclusively in the nervous system and control the resting membrane potential. Their gating is sensitive to polyunsaturated fatty acids, mechanical deformation of the membrane, and temperature changes. Physiologically, these channels appear to control the noxious input threshold for temperature and pressure sensitivity in dorsal root ganglia neurons. We present the crystal structure of human TRAAK at a resolution of 3.8 angstroms. The channel comprises two protomers, each containing two distinct pore domains, which create a two-fold symmetric K(+) channel. The extracellular surface features a helical cap, 35 angstroms tall, that creates a bifurcated pore entryway and accounts for the insensitivity of two-pore domain K(+) channels to inhibitory toxins. Two diagonally opposed gate-forming inner helices form membrane-interacting structures that may underlie this channel's sensitivity to chemical and mechanical properties of the cell membrane.


    Organizational Affiliation

    Laboratory of Molecular Neurobiology and Biophysics and Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Potassium channel subfamily K member 4
A, B
309Homo sapiensGene Names: KCNK4 (TRAAK)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
Two-Pore Domain Potassium Channel K2P4.1 (TRAAK)
Find proteins for Q9NYG8 (Homo sapiens)
Go to Gene View: KCNK4
Go to UniProtKB:  Q9NYG8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
A
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.31 Å
  • R-Value Free: 0.323 
  • R-Value Work: 0.317 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 87.938α = 90.00
b = 130.852β = 90.00
c = 132.779γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
HKL-2000data reduction
DMphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-02-08
    Type: Initial release