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 

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
    • A closed compact structure of native Ca(2+)-calmodulin
      Fallon, J.L.,Quiocho, F.A.
      (2003) Structure 11: 1303
    • 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

    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: CALM3 (CALML2, CAM3, CAMC, CAMIII)
Find proteins for P0DP25 (Homo sapiens)
Go to Gene View: CALM3
Go to UniProtKB:  P0DP25
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Voltage-dependent L-type calcium channel alpha-1C subunit
B
21Cavia porcellusMutation(s): 0 
Gene Names: CACNA1C
Find proteins for Q810C8 (Cavia porcellus)
Go to Gene View: CACNA1C
Go to UniProtKB:  Q810C8
Small Molecules
Ligands 2 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
MG
Query on MG
Download SDF File 
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 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 86.200α = 90.00
b = 30.960β = 114.54
c = 63.940γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
MAR345data collection
CNSrefinement
PDB_EXTRACTdata extraction
CNSphasing
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots


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
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-10-18
    Type: Refinement description