Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A2B1 

Biological assembly 1 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 40.42 kDa 
• Atom Count: 2935 
• Residue Count: 348 
• Unique protein chains: 2

2IX7

Structure of apo-calmodulin bound to unconventional myosin V

• DOI: 10.2210/pdb2IX7/pdb

• Classification: CONTRACTILE PROTEIN/METAL BINDING
• Organism(s): Mus musculus
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2006-07-07 Released: 2006-12-13 
• Deposition Author(s): Houdusse, A., Gaucher, J.F., Mui, S., Krementsova, E., Trybus, K.M., Cohen, C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.259 
• R-Value Work: 0.216 
• R-Value Observed: 0.216 

Literature

Crystal Structure of Apo-Calmodulin Bound to the First Two Iq Motifs of Myosin V Reveals Essential Recognition Features.

Houdusse, A., Gaucher, J.F., Krementsova, E., Mui, S., Trybus, K.M., Cohen, C.

(2006) Proc Natl Acad Sci U S A 103: 19326

• PubMed: 17151196 
• DOI: 10.1073/pnas.0609436103
• Primary Citation of Related Structures:  
  2IX7


• PubMed Abstract: 
  

A 2.5-A resolution structure of calcium-free calmodulin (CaM) bound to the first two IQ motifs of the murine myosin V heavy chain reveals an unusual CaM conformation. The C-terminal lobe of each CaM adopts a semi-open conformation that grips the first part of the IQ motif (IQxxxR), whereas the N-terminal lobe adopts a closed conformation that interacts more weakly with the second part of the motif (GxxxR). Variable residues in the IQ motif play a critical role in determining the precise structure of the bound CaM, such that even the consensus residues of different motifs show unique interactions with CaM. This complex serves as a model for the lever arm region of many classes of unconventional myosins, as well as other IQ motif-containing proteins such as neuromodulin and IQGAPs.

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Organizational Affiliation: 

Motilité Structurale, Institut Curie, Centre National de la Recherche Scientifique, Unite Mixté de Recherche 144, 26 rue d'Ulm, 75248, Paris Cedex 05, France.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CALMODULIN	A, B	145	Mus musculus	Mutation(s): 0  Gene Names: Calm1, Calm, Cam, Cam1
Find proteins for P0DP26 (Mus musculus) Explore P0DP26  Go to UniProtKB:  P0DP26

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
MYOSIN-5A	C	58	Mus musculus	Mutation(s): 0  Gene Names: Myo5a, Dilute
Find proteins for Q99104 (Mus musculus) Explore Q99104  Go to UniProtKB:  Q99104

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CYS	C	CYSTEINE C3 H7 N O2 S XUJNEKJLAYXESH-REOHCLBHSA-N
SO4	B, C	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.259 
• R-Value Work: 0.216 
• R-Value Observed: 0.216 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 112	α = 90
b = 112	β = 90
c = 102.34	γ = 120

Software Package:

Software Name	Purpose
CNS	refinement
MOSFLM	data reduction
SCALEPACK	data scaling
MLPHARE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-07-07 
• Released Date: 2006-12-13 
Deposition Author(s): Houdusse, A., Gaucher, J.F., Mui, S., Krementsova, E., Trybus, K.M., Cohen, C.

Revision History 

• Version 1.0: 2006-12-13
  Type: Initial release
  
• Version 1.1: 2013-12-04
  Changes: Data collection, Derived calculations, Non-polymer description, Other, Refinement description, Source and taxonomy, Version format compliance
• Version 1.2: 2019-02-27
  Changes: Data collection, Derived calculations, Experimental preparation, Other