7ZRQ

1.68 Angstrom crystal structure of Ca/CaM-E140G:CaMKIIdelta peptide complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.68 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.205 

Starting Model: experimental
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wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Calmodulin variant E140G associated with long QT syndrome impairs CaMKII delta autophosphorylation and L-type calcium channel inactivation.

Prakash, O.Gupta, N.Milburn, A.McCormick, L.Deugi, V.Fisch, P.Wyles, J.Thomas, N.L.Antonyuk, S.Dart, C.Helassa, N.

(2022) J Biol Chem 299: 102777-102777

  • DOI: https://doi.org/10.1016/j.jbc.2022.102777
  • Primary Citation of Related Structures:  
    7ZRP, 7ZRQ

  • PubMed Abstract: 

    Long QT syndrome (LQTS) is a human inherited heart condition that can cause life-threatening arrhythmia including sudden cardiac death. Mutations in the ubiquitous Ca 2+ -sensing protein calmodulin (CaM) are associated with LQTS, but the molecular mechanism by which these mutations lead to irregular heartbeats is not fully understood. Here, we use a multidisciplinary approach including protein biophysics, structural biology, confocal imaging, and patch-clamp electrophysiology to determine the effect of the disease-associated CaM mutation E140G on CaM structure and function. We present novel data showing that mutant-regulated CaMKIIδ kinase activity is impaired with a significant reduction in enzyme autophosphorylation rate. We report the first high-resolution crystal structure of a LQTS-associated CaM variant in complex with the CaMKIIδ peptide, which shows significant structural differences, compared to the WT complex. Furthermore, we demonstrate that the E140G mutation significantly disrupted Ca v 1.2 Ca 2+ /CaM-dependent inactivation, while cardiac ryanodine receptor (RyR2) activity remained unaffected. In addition, we show that the LQTS-associated mutation alters CaM's Ca 2+ -binding characteristics, secondary structure content, and interaction with key partners involved in excitation-contraction coupling (CaMKIIδ, Ca v 1.2, RyR2). In conclusion, LQTS-associated CaM mutation E140G severely impacts the structure-function relationship of CaM and its regulation of CaMKIIδ and Ca v 1.2. This provides a crucial insight into the molecular factors contributing to CaM-mediated arrhythmias with a central role for CaMKIIδ.


  • Organizational Affiliation

    Liverpool Centre for Cardiovascular Science, Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, United Kingdom.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Calmodulin-1148Homo sapiensMutation(s): 1 
Gene Names: CALM1CALMCAMCAM1
UniProt & NIH Common Fund Data Resources
Find proteins for P0DP23 (Homo sapiens)
Explore P0DP23 
Go to UniProtKB:  P0DP23
PHAROS:  P0DP23
GTEx:  ENSG00000198668 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0DP23
Sequence Annotations
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  • Reference Sequence

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Calcium/calmodulin-dependent protein kinase type II subunit delta22Homo sapiensMutation(s): 0 
EC: 2.7.11.17
UniProt & NIH Common Fund Data Resources
Find proteins for Q13557 (Homo sapiens)
Explore Q13557 
Go to UniProtKB:  Q13557
PHAROS:  Q13557
GTEx:  ENSG00000145349 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ13557
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.68 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.205 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 41.38α = 90
b = 54.52β = 90
c = 57.5γ = 90
Software Package:
Software NamePurpose
XDSdata reduction
Aimlessdata scaling
MOLREPphasing
REFMACrefinement

Structure Validation

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Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
British Heart FoundationUnited KingdomFS/17/56/32925
Wellcome TrustUnited Kingdom102172/B/13/Z

Revision History  (Full details and data files)

  • Version 1.0: 2022-12-28
    Type: Initial release
  • Version 1.1: 2023-01-11
    Changes: Database references
  • Version 1.2: 2024-01-31
    Changes: Data collection, Refinement description