2KBI

Solution NMR structure of the C-terminal EF-hand domain of human cardiac sodium channel NaV1.5


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Solution NMR Structure of the C-terminal EF-hand Domain of Human Cardiac Sodium Channel NaV1.5.

Chagot, B.Potet, F.Balser, J.R.Chazin, W.J.

(2009) J Biol Chem 284: 6436-6445

  • DOI: https://doi.org/10.1074/jbc.M807747200
  • Primary Citation of Related Structures:  
    2KBI

  • PubMed Abstract: 

    The voltage-gated sodium channel NaV1.5 is responsible for the initial upstroke of the action potential in cardiac tissue. Levels of intracellular calcium modulate inactivation gating of NaV1.5, in part through a C-terminal EF-hand calcium binding domain. The significance of this structure is underscored by the fact that mutations within this domain are associated with specific cardiac arrhythmia syndromes. In an effort to elucidate the molecular basis for calcium regulation of channel function, we have determined the solution structure of the C-terminal EF-hand domain using multidimensional heteronuclear NMR. The structure confirms the existence of the four-helix bundle common to EF-hand domain proteins. However, the location of this domain is shifted with respect to that predicted on the basis of a consensus 12-residue EF-hand calcium binding loop in the sequence. This finding is consistent with the weak calcium affinity reported for the isolated EF-hand domain; high affinity binding is observed only in a construct with an additional 60 residues C-terminal to the EF-hand domain, including the IQ motif that is central to the calcium regulatory apparatus. The binding of an IQ motif peptide to the EF-hand domain was characterized by isothermal titration calorimetry and nuclear magnetic resonance spectroscopy. The peptide binds between helices I and IV in the EF-hand domain, similar to the binding of target peptides to other EF-hand calcium-binding proteins. These results suggest a molecular basis for the coupling of the intrinsic (EF-hand domain) and extrinsic (calmodulin) components of the calcium-sensing apparatus of NaV1.5.


  • Organizational Affiliation

    Department of Anesthesiology, Center for Structural Biology, Vanderbilt University, Nashville, Tennessee 37232-8725, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Sodium channel protein type 5 subunit alpha97Homo sapiensMutation(s): 0 
Gene Names: SCN5A
UniProt & NIH Common Fund Data Resources
Find proteins for Q14524 (Homo sapiens)
Explore Q14524 
Go to UniProtKB:  Q14524
PHAROS:  Q14524
GTEx:  ENSG00000183873 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ14524
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-12-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2022-03-16
    Changes: Data collection, Database references, Derived calculations
  • Version 1.3: 2024-05-22
    Changes: Data collection