Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content

• Total Structure Weight: 110.11 kDa 
• Atom Count: 7058 
• Modelled Residue Count: 907 
• Deposited Residue Count: 971 
• Unique protein chains: 2

4I2Z

Crystal structure of the myosin chaperone UNC-45 from C.elegans in complex with a Hsp90 peptide

• DOI: 10.2210/pdb4I2Z/pdb

• Classification: Chaperone/protein binding
• Organism(s): Caenorhabditis elegans
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2012-11-23 Released: 2013-03-13 
• Deposition Author(s): Clausen, T., Gazda, L., Hellerschmied, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.256 
• R-Value Work: 0.237 
• R-Value Observed: 0.238 

Literature

The myosin chaperone UNC-45 is organized in tandem modules to support myofilament formation in C. elegans.

Gazda, L., Pokrzywa, W., Hellerschmied, D., Lowe, T., Forne, I., Mueller-Planitz, F., Hoppe, T., Clausen, T.

(2013) Cell 152: 183-195

• PubMed: 23332754 
• DOI: 10.1016/j.cell.2012.12.025
• Primary Citation of Related Structures:  
  4I2W, 4I2Z


• PubMed Abstract: 
  

The UCS (UNC-45/CRO1/She4) chaperones play an evolutionarily conserved role in promoting myosin-dependent processes, including cytokinesis, endocytosis, RNA transport, and muscle development. To investigate the protein machinery orchestrating myosin folding and assembly, we performed a comprehensive analysis of Caenorhabditis elegans UNC-45. Our structural and biochemical data demonstrate that UNC-45 forms linear protein chains that offer multiple binding sites for cooperating chaperones and client proteins. Accordingly, Hsp70 and Hsp90, which bind to the TPR domain of UNC-45, could act in concert and with defined periodicity on captured myosin molecules. In vivo analyses reveal the elongated canyon of the UCS domain as a myosin-binding site and show that multimeric UNC-45 chains support organization of sarcomeric repeats. In fact, expression of transgenes blocking UNC-45 chain formation induces dominant-negative defects in the sarcomere structure and function of wild-type worms. Together, these findings uncover a filament assembly factor that directly couples myosin folding with myofilament formation.

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Organizational Affiliation: 

Research Institute of Molecular Pathology, Dr. Bohrgasse 7, 1030 Vienna, Austria.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein UNC-45	A	961	Caenorhabditis elegans	Mutation(s): 0  Gene Names: unc-45, CELE_F30H5.1, F30H5.1
Find proteins for G5EG62 (Caenorhabditis elegans) Explore G5EG62  Go to UniProtKB:  G5EG62

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Heat shock protein 90	B	10	Caenorhabditis elegans	Mutation(s): 0  Gene Names: daf-21, C47E8.5
Find proteins for Q18688 (Caenorhabditis elegans) Explore Q18688  Go to UniProtKB:  Q18688

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.256 
• R-Value Work: 0.237 
• R-Value Observed: 0.238 
• Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 86.633	α = 90
b = 86.633	β = 90
c = 815.015	γ = 120

Software Package:

Software Name	Purpose
SHARP	phasing
PHENIX	refinement
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-11-23 
• Released Date: 2013-03-13 
Deposition Author(s): Clausen, T., Gazda, L., Hellerschmied, D.

Revision History  

• Version 1.0: 2013-03-13
  Type: Initial release