6MC9

Crystal Structure of Human Nav1.4 C-Terminal (1599-1754) domain in complex with calcium-bound calmodulin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.30 Å
  • R-Value Free: 0.285 
  • R-Value Work: 0.240 
  • R-Value Observed: 0.242 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Ca2+-dependent regulation of sodium channels NaV1.4 and NaV1.5 is controlled by the post-IQ motif.

Yoder, J.B.Ben-Johny, M.Farinelli, F.Srinivasan, L.Shoemaker, S.R.Tomaselli, G.F.Gabelli, S.B.Amzel, L.M.

(2019) Nat Commun 10: 1514-1514

  • DOI: 10.1038/s41467-019-09570-7
  • Primary Citation of Related Structures:  
    6MBA, 6MC9

  • PubMed Abstract: 
  • Skeletal muscle voltage-gated Na + channel (Na V 1.4) activity is subject to calmodulin (CaM) mediated Ca 2+ -dependent inactivation; no such inactivation is observed in the cardiac Na + channel (Na V 1 ...

    Skeletal muscle voltage-gated Na + channel (Na V 1.4) activity is subject to calmodulin (CaM) mediated Ca 2+ -dependent inactivation; no such inactivation is observed in the cardiac Na + channel (Na V 1.5). Taken together, the crystal structures of the Na V 1.4 C-terminal domain relevant complexes and thermodynamic binding data presented here provide a rationale for this isoform difference. A Ca 2+ -dependent CaM N-lobe binding site previously identified in Na V 1.5 is not present in Na V 1.4 allowing the N-lobe to signal other regions of the Na V 1.4 channel. Consistent with this mechanism, removing this binding site in Na V 1.5 unveils robust Ca 2+ -dependent inactivation in the previously insensitive isoform. These findings suggest that Ca 2+ -dependent inactivation is effected by CaM's N-lobe binding outside the Na V C-terminal while CaM's C-lobe remains bound to the Na V C-terminal. As the N-lobe binding motif of Na V 1.5 is a mutational hotspot for inherited arrhythmias, the contributions of mutation-induced changes in CDI to arrhythmia generation is an intriguing possibility.


    Organizational Affiliation

    Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA. mamzel@jhmi.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Sodium channel protein type 4 subunit alphaA168Homo sapiensMutation(s): 0 
Gene Names: SCN4A
Find proteins for P35499 (Homo sapiens)
Explore P35499 
Go to UniProtKB:  P35499
NIH Common Fund Data Resources
PHAROS  P35499
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Calmodulin-1B149Rattus norvegicusMutation(s): 0 
Gene Names: Calm1CalmCamCam1CaMI
Find proteins for P0DP29 (Rattus norvegicus)
Explore P0DP29 
Go to UniProtKB:  P0DP29
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download CCD File 
B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.30 Å
  • R-Value Free: 0.285 
  • R-Value Work: 0.240 
  • R-Value Observed: 0.242 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72.615α = 90
b = 72.615β = 90
c = 134.661γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata reduction
XSCALEdata scaling
PDB_EXTRACTdata extraction
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Heart, Lung, and Blood Institute (NIH/NHLBI)United States5R01HL128743

Revision History 

  • Version 1.0: 2019-04-10
    Type: Initial release
  • Version 1.1: 2019-04-17
    Changes: Data collection, Database references
  • Version 1.2: 2019-12-04
    Changes: Author supporting evidence