4CHW

The electron crystallography structure of the cAMP-free potassium channel MloK1


Experimental Data Snapshot

  • Method: ELECTRON CRYSTALLOGRAPHY
  • Resolution: 7.00 Å

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Ligand-induced structural changes in the cyclic nucleotide-modulated potassium channel MloK1.

Kowal, J.Chami, M.Baumgartner, P.Arheit, M.Chiu, P.L.Rangl, M.Scheuring, S.Schroder, G.F.Nimigean, C.M.Stahlberg, H.

(2014) Nat Commun 5: 3106-3106

  • DOI: 10.1038/ncomms4106
  • Primary Citation of Related Structures:  
    4CHV, 4CHW

  • PubMed Abstract: 
  • Cyclic nucleotide-modulated ion channels are important for signal transduction and pacemaking in eukaryotes. The molecular determinants of ligand gating in these channels are still unknown, mainly because of a lack of direct structural information. H ...

    Cyclic nucleotide-modulated ion channels are important for signal transduction and pacemaking in eukaryotes. The molecular determinants of ligand gating in these channels are still unknown, mainly because of a lack of direct structural information. Here we report ligand-induced conformational changes in full-length MloK1, a cyclic nucleotide-modulated potassium channel from the bacterium Mesorhizobium loti, analysed by electron crystallography and atomic force microscopy. Upon cAMP binding, the cyclic nucleotide-binding domains move vertically towards the membrane, and directly contact the S1-S4 voltage sensor domains. This is accompanied by a significant shift and tilt of the voltage sensor domain helices. In both states, the inner pore-lining helices are in an 'open' conformation. We propose a mechanism in which ligand binding can favour pore opening via a direct interaction between the cyclic nucleotide-binding domains and voltage sensors. This offers a simple mechanistic hypothesis for the coupling between ligand gating and voltage sensing in eukaryotic HCN channels.


    Organizational Affiliation

    Center for Cellular Imaging and NanoAnalytics, Biozentrum, University of Basel, Mattenstrasse 26, CH-4058 Basel, Switzerland.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CYCLIC NUCLEOTIDE-GATED POTASSIUM CHANNEL MLL3241ABCD361Mesorhizobium lotiMutation(s): 0 
Find proteins for Q98GN8 (Mesorhizobium japonicum (strain LMG 29417 / CECT 9101 / MAFF 303099))
Explore Q98GN8 
Go to UniProtKB:  Q98GN8
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

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

Experimental Data

  • Method: ELECTRON CRYSTALLOGRAPHY
  • Resolution: 7.00 Å
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.3α = 90
b = 105.3β = 90
c = 105.3γ = 90

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-01-15
    Type: Initial release
  • Version 1.1: 2014-02-12
    Changes: Database references
  • Version 1.2: 2018-02-28
    Changes: Source and taxonomy
  • Version 1.3: 2018-08-01
    Changes: Data collection, Database references
  • Version 1.4: 2019-04-24
    Changes: Data collection, Other