2F3Y

Calmodulin/IQ domain complex

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history. 


Literature

Structure of Calmodulin Bound to the Hydrophobic IQ Domain of the Cardiac Ca(v)1.2 Calcium Channel.

Fallon, J.L., Halling, D.B., Hamilton, S.L., Quiocho, F.A.

(2005) Structure 13: 1881-1886

  • DOI: 10.1016/j.str.2005.09.021
  • Primary Citation of Related Structures:  
    2F3Z, 2F3Y

  • PubMed Abstract: 

    • Ca2+-dependent inactivation (CDI) and facilitation (CDF) of the Ca(v)1.2 Ca2+ channel require calmodulin binding to a putative IQ motif in the carboxy-terminal tail of the pore-forming subunit. We present the 1.45 A crystal structure of Ca2+-calmodul ...

    Ca2+-dependent inactivation (CDI) and facilitation (CDF) of the Ca(v)1.2 Ca2+ channel require calmodulin binding to a putative IQ motif in the carboxy-terminal tail of the pore-forming subunit. We present the 1.45 A crystal structure of Ca2+-calmodulin bound to a 21 residue peptide corresponding to the IQ domain of Ca(v)1.2. This structure shows that parallel binding of calmodulin to the IQ domain is governed by hydrophobic interactions. Mutations of residues I1672 and Q1673 in the peptide to alanines, which abolish CDI but not CDF in the channel, do not greatly alter the structure. Both lobes of Ca2+-saturated CaM bind to the IQ peptide but isoleucine 1672, thought to form an intramolecular interaction that drives CDI, is buried. These findings suggest that this structure could represent the conformation that calmodulin assumes in CDF.

    Related Citations: 
    • Calmodulin interactions with IQ peptides from voltage-dependent calcium channels
      Black, D.J., Halling, D.B., Mandich, D.V., Pedersen, S.E., Altshuld, R.A., Hamilton, S.L.
      (2005) Am J Physiol Cell Physiol 288: C669
    • Target enzyme recognition by calmodulin: 2.4 A structure of a calmodulin-peptide complex
      Meador, W.E., Means, A.R., Quiocho, F.A.
      (1992) Science 257: 1251
    • A closed compact structure of native Ca(2+)-calmodulin
      Fallon, J.L., Quiocho, F.A.
      (2003) Structure 11: 1303
    Organizational Affiliation: 

    Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.



Macromolecules
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
CalmodulinA148Homo sapiensMutation(s): 0 
Gene Names: CALM1, calm2, calm3, CALM, CAM, CAM1
Find proteins for P0DP23 (Homo sapiens)
Explore P0DP23 
Go to UniProtKB:  P0DP23
NIH Common Fund Data Resources
PHAROS  P0DP23
GTEx  ENSG00000198668
Protein Feature View
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  • Reference Sequence
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Voltage-dependent L-type calcium channel alpha-1C subunitB21N/AMutation(s): 0 
Find proteins for Q13936 (Homo sapiens)
Explore Q13936 
Go to UniProtKB:  Q13936
NIH Common Fund Data Resources
PHAROS  Q13936
GTEx  ENSG00000151067
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA
Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N		 Ligand Interaction
MG
Query on MG
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N		 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.45 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 86.2α = 90
b = 30.96β = 114.54
c = 63.94γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing
CNSrefinement
PDB_EXTRACTdata extraction
MAR345data collection

Structure Validation

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View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-12-27
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-10-18
    Changes: Refinement description