2L1M

Solution structure of the eag domain of the hERG (Kv11.1) K+ channel


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Mechanistic insight into human ether-a-go-go-related gene (hERG) K+ channel deactivation gating from the solution structure of the EAG domain.

Muskett, F.W.Thouta, S.Thomson, S.J.Bowen, A.Stansfeld, P.J.Mitcheson, J.S.

(2011) J.Biol.Chem. 286: 6184-6191

  • DOI: 10.1074/jbc.M110.199364

  • PubMed Abstract: 
  • Human ether-à-go-go-related gene (hERG) K(+) channels have a critical role in cardiac repolarization. hERG channels close (deactivate) very slowly, and this is vital for regulating the time course and amplitude of repolarizing current during the card ...

    Human ether-à-go-go-related gene (hERG) K(+) channels have a critical role in cardiac repolarization. hERG channels close (deactivate) very slowly, and this is vital for regulating the time course and amplitude of repolarizing current during the cardiac action potential. Accelerated deactivation is one mechanism by which inherited mutations cause long QT syndrome and potentially lethal arrhythmias. hERG deactivation is highly dependent upon an intact EAG domain (the first 135 amino acids of the N terminus). Importantly, deletion of residues 2-26 accelerates deactivation to a similar extent as removing the entire EAG domain. These and other experiments suggest the first 26 residues (NT1-26) contain structural elements required to slow deactivation by stabilizing the open conformation of the pore. Residues 26-135 form a Per-Arnt-Sim domain, but a structure for NT1-26 has not been forthcoming, and little is known about its site of interaction on the channel. In this study, we present an NMR structure for the entire EAG domain, which reveals that NT1-26 is structurally independent from the Per-Arnt-Sim domain and contains a stable amphipathic helix with one face being positively charged. Mutagenesis and electrophysiological studies indicate that neutralizing basic residues and breaking the amphipathic helix dramatically accelerate deactivation. Furthermore, scanning mutagenesis and molecular modeling studies of the cyclic nucleotide binding domain suggest that negatively charged patches on its cytoplasmic surface form an interface with the NT1-26 domain. We propose a model in which NT1-26 obstructs gating motions of the cyclic nucleotide binding domain to allosterically stabilize the open conformation of the pore.


    Organizational Affiliation

    Department of Biochemistry, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 9HN, United Kingdom. fwm1@le.ac.uk




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Potassium voltage-gated channel subfamily H member 2
A
150Homo sapiensMutation(s): 0 
Gene Names: KCNH2 (ERG, ERG1, HERG)
Find proteins for Q12809 (Homo sapiens)
Go to Gene View: KCNH2
Go to UniProtKB:  Q12809
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2L1M Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-01-19
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance