2BE6

2.0 A crystal structure of the CaV1.2 IQ domain-Ca/CaM complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.202 
  • R-Value Observed: 0.205 

wwPDB Validation   3D Report Full Report


This is version 1.5 of the entry. See complete history


Literature

Insights into voltage-gated calcium channel regulation from the structure of the Ca(V)1.2 IQ domain-Ca(2+)/calmodulin complex

van Petegem, F.Chatelain, F.C.Minor Jr., D.L.

(2005) Nat Struct Mol Biol 12: 1108-1115

  • DOI: https://doi.org/10.1038/nsmb1027
  • Primary Citation of Related Structures:  
    2BE6

  • PubMed Abstract: 

    Changes in activity-dependent calcium flux through voltage-gated calcium channels (Ca(V)s) drive two self-regulatory calcium-dependent feedback processes that require interaction between Ca(2+)/calmodulin (Ca(2+)/CaM) and a Ca(V) channel consensus isoleucine-glutamine (IQ) motif: calcium-dependent inactivation (CDI) and calcium-dependent facilitation (CDF). Here, we report the high-resolution structure of the Ca(2+)/CaM-Ca(V)1.2 IQ domain complex. The IQ domain engages hydrophobic pockets in the N-terminal and C-terminal Ca(2+)/CaM lobes through sets of conserved 'aromatic anchors.' Ca(2+)/N lobe adopts two conformations that suggest inherent conformational plasticity at the Ca(2+)/N lobe-IQ domain interface. Titration calorimetry experiments reveal competition between the lobes for IQ domain sites. Electrophysiological examination of Ca(2+)/N lobe aromatic anchors uncovers their role in Ca(V)1.2 CDF. Together, our data suggest that Ca(V) subtype differences in CDI and CDF are tuned by changes in IQ domain anchoring positions and establish a framework for understanding CaM lobe-specific regulation of Ca(V)s.


  • Organizational Affiliation

    Cardiovascular Research Institute, Department of Biochemistry and Biophysics, California Institute for Quantitative Biomedical Research, University of California, San Francisco, 1700 4th St., Box 2532, San Francisco, California 94143-2532, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Calmodulin 2A,
C [auth B],
E [auth C]
150Homo sapiensMutation(s): 0 
Gene Names: CALM2
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:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Voltage-dependent L-type calcium channel alpha-1C subunitB [auth D],
D [auth E],
F
37Homo sapiensMutation(s): 0 
Gene Names: CACNA1CCACH2CACN2CACNL1A1CCHL1A1
UniProt & NIH Common Fund Data Resources
Find proteins for Q13936 (Homo sapiens)
Explore Q13936 
Go to UniProtKB:  Q13936
PHAROS:  Q13936
GTEx:  ENSG00000151067 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ13936
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
NI
Query on NI

Download Ideal Coordinates CCD File 
K [auth A],
P [auth B],
U [auth C]
NICKEL (II) ION
Ni
VEQPNABPJHWNSG-UHFFFAOYSA-N
CA
Query on CA

Download Ideal Coordinates CCD File 
G [auth A]
H [auth A]
I [auth A]
J [auth A]
L [auth B]
G [auth A],
H [auth A],
I [auth A],
J [auth A],
L [auth B],
M [auth B],
N [auth B],
O [auth B],
Q [auth C],
R [auth C],
S [auth C],
T [auth C]
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.255 
  • R-Value Work: 0.202 
  • R-Value Observed: 0.205 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 84.731α = 90
b = 37.241β = 97.77
c = 86.86γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
HKL-2000data reduction
HKL-2000data scaling
SHARPphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2005-11-15
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Advisory, Version format compliance
  • Version 1.3: 2017-10-18
    Changes: Refinement description
  • Version 1.4: 2022-12-21
    Changes: Database references, Derived calculations
  • Version 1.5: 2024-05-22
    Changes: Data collection