Biological Assembly 1  

 3D View: Structure | Ligand Interaction

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - AB 

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

Macromolecule Content

• Total Structure Weight: 45761.13 
• Atom Count: 3067 
• Residue Count: 402 
• Unique protein chains: 2

1SQK

CRYSTAL STRUCTURE OF CIBOULOT IN COMPLEX WITH SKELETAL ACTIN

• DOI: 10.2210/pdb1SQK/pdb

• Classification: STRUCTURAL PROTEIN/PROTEIN BINDING
• Organism(s): Drosophila melanogaster, Oryctolagus cuniculus
• Expression System: Escherichia coli


• Deposited: 2004-03-19 Released: 2004-06-15 
• Deposition Author(s): Hertzog, M., Van Heijenoort, C., Didry, D., Gaudier, M., Gigant, B., Coutant, J., Didelot, G., Preat, T., Knossow, M., Guittet, E., Carlier, M.F.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.5 Å
• R-Value Free: 0.278 
• R-Value Work: 0.219 

Literature

The beta-Thymosin/WH2 Domain; Structural Basis for the Switch from Inhibition to Promotion of Actin Assembly

Hertzog, M., Van Heijenoort, C., Didry, D., Gaudier, M., Coutant, J., Gigant, B., Didelot, G., Knossow, M., Guittet, E., Carlier, M.F.

(2004) Cell 117: 611-623

• PubMed: 15163409 
• Also Cited By: 3U9Z, 3U9D


• PubMed Abstract: 
  

The widespread beta-thymosin/WH2 actin binding domain has versatile regulatory properties in actin dynamics and motility. beta-thymosins (isolated WH2 domain) maintain monomeric actin in a "sequestered" nonpolymerizable form. In contrast, when repeated in tandem or inserted in modular proteins, the beta-thymosin/WH2 domain promotes actin assembly at filament barbed ends, like profilin. The structural basis for these opposite functions is addressed using ciboulot, a three beta-thymosin repeat protein. Only the first repeat binds actin and possesses the function of ciboulot. The region that shows the strongest interaction with actin is an amphipathic N-terminal alpha helix, present in all beta-thymosin/WH2 domains, which recognizes the ATP bound actin structure and uses the shear motion of actin linked to ATP hydrolysis to control polymerization. Crystallographic ((1)H, (15)N), NMR, and mutagenetic data reveal that the weaker interaction of the C-terminal region of beta-thymosin/WH2 domain with actin accounts for the switch in function from inhibition to promotion of actin assembly.

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Organizational Affiliation: 

Dynamique du Cytosquelette, Laboratoire d'Enzymologie et Biochimie Structurales, Institut Alfred Fessard, Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette, France.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
ACTIN, ALPHA SKELETAL MUSCLE	A	377	Oryctolagus cuniculus	Mutation(s): 0  Gene Names: ACTA1 (ACTA)
Find proteins for P68135 (Oryctolagus cuniculus) Go to Gene View: ACTA1 Go to UniProtKB:  P68135

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
CIBOULOT	B	25	Drosophila melanogaster	Mutation(s): 0  Gene Names: cib (Dmel\CG4944, EG0007-11, EG:EG0007.11)
Find proteins for O97428 (Drosophila melanogaster) Go to UniProtKB:  O97428

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
ADP	A	ADENOSINE-5'-DIPHOSPHATE C10 H15 N5 O10 P2 XTWYTFMLZFPYCI-KQYNXXCUSA-N
LAR	A	LATRUNCULIN A 4-(17-HYDROXY-5,12-DIMETHYL-3-OXO-2,16-DIOXABICYCLO[13.3.1]NONADECA-4,8,10-TRIEN-17-YL)-2-THIAZOLIDINONE C22 H31 N O5 S DDVBPZROPPMBLW-IZGXTMSKSA-N
MG	A	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
LAR	IC50: 40 - 110 nM (86) BINDINGDB

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.5 Å
• R-Value Free: 0.278 
• R-Value Work: 0.219 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 67.494	α = 90.00
b = 75.198	β = 90.00
c = 85.314	γ = 90.00

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
DENZO	data reduction
CNS	refinement
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-03-19 
• Released Date: 2004-06-15 
• Deposition Author(s): Hertzog, M., Van Heijenoort, C., Didry, D., Gaudier, M., Gigant, B., Coutant, J., Didelot, G., Preat, T., Knossow, M., Guittet, E., Carlier, M.F.

Revision History 

• Version 1.0: 2004-06-15
  Type: Initial release
• Version 1.1: 2008-04-29
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance