Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B 

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

Macromolecule Content

• Total Structure Weight: 58.53 kDa 
• Atom Count: 4420 
• Residue Count: 502 
• Unique protein chains: 2

1T44

Structural basis of actin sequestration by thymosin-B4: Implications for arp2/3 activation

• DOI: 10.2210/pdb1T44/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Homo sapiens, Mus musculus, Oryctolagus cuniculus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2004-04-28 Released: 2004-09-07 
• Deposition Author(s): Irobi, E., Aguda, A.H., Larsson, M., Burtnick, L.D., Robinson, R.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.195 
• R-Value Work: 0.144 
• R-Value Observed: 0.147 

Literature

Structural basis of actin sequestration by thymosin-beta4: implications for WH2 proteins.

Irobi, E., Aguda, A.H., Larsson, M., Guerin, C., Yin, H.L., Burtnick, L.D., Blanchoin, L., Robinson, R.C.

(2004) EMBO J 23: 3599-3608

• PubMed: 15329672 
• DOI: 10.1038/sj.emboj.7600372
• Structures With Same Primary Citation


• PubMed Abstract: 
  

The WH2 (Wiscott-Aldridge syndrome protein homology domain 2) repeat is an actin interacting motif found in monomer sequestering and filament assembly proteins. We have stabilized the prototypical WH2 family member, thymosin-beta4 (Tbeta4), with respect to actin, by creating a hybrid between gelsolin domain 1 and the C-terminal half of Tbeta4 (G1-Tbeta4). This hybrid protein sequesters actin monomers, severs actin filaments and acts as a leaky barbed end cap. Here, we present the structure of the G1-Tbeta4:actin complex at 2 A resolution. The structure reveals that Tbeta4 sequesters by capping both ends of the actin monomer, and that exchange of actin between Tbeta4 and profilin is mediated by a minor overlap in binding sites. The structure implies that multiple WH2 motif-containing proteins will associate longitudinally with actin filaments. Finally, we discuss the role of the WH2 motif in arp2/3 activation.

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Organizational Affiliation: 

Department of Medical Biochemistry and Microbiology, Uppsala Biomedical Center, Uppsala University, Uppsala, Sweden.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Chimera of Gelsolin domain 1 and C-Terminal domain of thymosin Beta-4	G	147	Homo sapiens, Mus musculus This entity is chimeric	Mutation(s): 0  Gene Names: GSN
Find proteins for P06396 (Homo sapiens) Go to UniProtKB:  P06396
NIH Common Fund Data Resources
PHAROS  P06396 GTEx  ENSG00000148180

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Actin, alpha	A	370	Oryctolagus cuniculus	Mutation(s): 0  Gene Names: ACTA1, ACTA
Find proteins for P68135 (Oryctolagus cuniculus) Go to UniProtKB:  P68135

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ATP	A	ADENOSINE-5'-TRIPHOSPHATE C10 H16 N5 O13 P3 ZKHQWZAMYRWXGA-KQYNXXCUSA-N
CA	A, G	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.195 
• R-Value Work: 0.144 
• R-Value Observed: 0.147 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 56.85	α = 90
b = 69.335	β = 94.93
c = 80.233	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2004-04-28 
• Released Date: 2004-09-07 
Deposition Author(s): Irobi, E., Aguda, A.H., Larsson, M., Burtnick, L.D., Robinson, R.C.

Revision History 

• Version 1.0: 2004-09-07
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2017-08-23
  Changes: Source and taxonomy