2VAY

Calmodulin complexed with CaV1.1 IQ peptide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.94 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.218 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Determinants in Cav1 Channels that Regulate the Ca2+ Sensitivity of Bound Calmodulin.

Halling, D.B.Georgiou, D.K.Black, D.J.Yang, G.Fallon, J.L.Quiocho, F.A.Pedersen, S.E.Hamilton, S.L.

(2009) J.Biol.Chem. 284: 20041

  • DOI: 10.1074/jbc.M109.013326

  • PubMed Abstract: 
  • Calmodulin binds to IQ motifs in the alpha(1) subunit of Ca(V)1.1 and Ca(V)1.2, but the affinities of calmodulin for the motif and for Ca(2+) are higher when bound to Ca(V)1.2 IQ. The Ca(V)1.1 IQ and Ca(V)1.2 IQ sequences differ by four amino acids. ...

    Calmodulin binds to IQ motifs in the alpha(1) subunit of Ca(V)1.1 and Ca(V)1.2, but the affinities of calmodulin for the motif and for Ca(2+) are higher when bound to Ca(V)1.2 IQ. The Ca(V)1.1 IQ and Ca(V)1.2 IQ sequences differ by four amino acids. We determined the structure of calmodulin bound to Ca(V)1.1 IQ and compared it with that of calmodulin bound to Ca(V)1.2 IQ. Four methionines in Ca(2+)-calmodulin form a hydrophobic binding pocket for the peptide, but only one of the four nonconserved amino acids (His-1532 of Ca(V)1.1 and Tyr-1675 of Ca(V)1.2) contacts this calmodulin pocket. However, Tyr-1675 in Ca(V)1.2 contributes only modestly to the higher affinity of this peptide for calmodulin; the other three amino acids in Ca(V)1.2 contribute significantly to the difference in the Ca(2+) affinity of the bound calmodulin despite having no direct contact with calmodulin. Those residues appear to allow an interaction with calmodulin with one lobe Ca(2+)-bound and one lobe Ca(2+)-free. Our data also provide evidence for lobe-lobe interactions in calmodulin bound to Ca(V)1.2.


    Organizational Affiliation

    Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CALMODULIN
A
146Homo sapiensMutation(s): 0 
Gene Names: CALM2 (CAM2, CAMB)
Find proteins for P0DP24 (Homo sapiens)
Go to Gene View: CALM2
Go to UniProtKB:  P0DP24
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
VOLTAGE-DEPENDENT L-TYPE CALCIUM CHANNEL SUBUNIT ALPHA-1S
B
21Homo sapiensMutation(s): 0 
Gene Names: CACNA1S (CACH1, CACN1, CACNL1A3)
Find proteins for Q13698 (Homo sapiens)
Go to Gene View: CACNA1S
Go to UniProtKB:  Q13698
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
B
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
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: 1.94 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.218 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 84.920α = 90.00
b = 34.670β = 113.69
c = 62.980γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
SCALEPACKdata scaling
CNSphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-09-16
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance