3U6N

Open Structure of the BK channel Gating Ring


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.61 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.260 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Open structure of the Ca(2+) gating ring in the high-conductance Ca(2+)-activated K(+) channel.

Yuan, P.Leonetti, M.D.Hsiung, Y.Mackinnon, R.

(2011) Nature 481: 94-97

  • DOI: 10.1038/nature10670

  • PubMed Abstract: 
  • High-conductance voltage- and Ca(2+)-activated K(+) channels function in many physiological processes that link cell membrane voltage and intracellular Ca(2+) concentration, including neuronal electrical activity, skeletal and smooth muscle contracti ...

    High-conductance voltage- and Ca(2+)-activated K(+) channels function in many physiological processes that link cell membrane voltage and intracellular Ca(2+) concentration, including neuronal electrical activity, skeletal and smooth muscle contraction, and hair cell tuning. Like other voltage-dependent K(+) channels, Ca(2+)-activated K(+) channels open when the cell membrane depolarizes, but in contrast to other voltage-dependent K(+) channels, they also open when intracellular Ca(2+) concentrations rise. Channel opening by Ca(2+) is made possible by a structure called the gating ring, which is located in the cytoplasm. Recent structural studies have defined the Ca(2+)-free, closed, conformation of the gating ring, but the Ca(2+)-bound, open, conformation is not yet known. Here we present the Ca(2+)-bound conformation of the gating ring. This structure shows how one layer of the gating ring, in response to the binding of Ca(2+), opens like the petals of a flower. The degree to which it opens explains how Ca(2+) binding can open the transmembrane pore. These findings present a molecular basis for Ca(2+) activation of K(+) channels and suggest new possibilities for targeting the gating ring to treat conditions such as asthma and hypertension.


    Organizational Affiliation

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




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
High-Conductance Ca2+-Activated K+ Channel protein
A, B, C, D, E, F, G, H
696Danio rerioGene Names: kcnma1b
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Potassium, Sodium, & Proton Ion-Selective
Protein: 
BK (SLO1) Channel Ca2+ gating ring from zebra fish in the open state
Find proteins for B7ZC96 (Danio rerio)
Go to UniProtKB:  B7ZC96
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.61 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.260 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 137.648α = 90.00
b = 210.816β = 90.00
c = 238.758γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
HKL-2000data collection
REFMACrefinement
HKL-2000data reduction
SCALEPACKdata scaling
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-12-07
    Type: Initial release
  • Version 1.1: 2012-01-11
    Type: Database references
  • Version 1.2: 2017-06-28
    Type: Database references, Source and taxonomy