2F3Z

Calmodulin/IQ-AA domain complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.219 

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:  
  • Also Cited By: 3G43

  • 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: 
    • 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
    • Calmodulin interactions with IO peptides from voltage-dependent calcium channels
      J Black, D.,Halling, D.B.,Mandich, D.V.,Pedersen, S.E.,Altshuld, R.A.,Hamilton, S.L.
      (2005) Am.J.Physiol., Cell Physiol. 288: C669
    • A closed compact structure of native Ca2+-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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Calmodulin
A
148Homo sapiensMutation(s): 0 
Gene Names: CALM1 (CALM, CAM, CAM1)
Find proteins for P0DP23 (Homo sapiens)
Go to Gene View: CALM1
Go to UniProtKB:  P0DP23
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Voltage-dependent L-type calcium channel alpha-1C subunit
B
21Homo sapiensMutation(s): 2 
Gene Names: CACNA1C (CACH2, CACN2, CACNL1A1, CCHL1A1)
Find proteins for Q13936 (Homo sapiens)
Go to Gene View: CACNA1C
Go to UniProtKB:  Q13936
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

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

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.6 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.219 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 86.260α = 90.00
b = 31.370β = 115.89
c = 64.110γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
PDB_EXTRACTdata extraction
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing
MAR345data collection

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

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