6QDK | pdb_00006qdk

Molecular features of the UNC-45 chaperone critical for binding and folding muscle myosin

• PDB DOI: https://doi.org/10.2210/pdb6QDK/pdb

• Classification: CHAPERONE
• Organism(s): Caenorhabditis elegans
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2019-01-02 Released: 2019-10-30 
• Deposition Author(s): Meinhart, A., Clausen, T., Hellerschmied, D.
• Funding Organization(s): Austrian Science Fund

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free: 
  0.319 (Depositor), 0.294 (DCC) 
• R-Value Work: 
  0.287 (Depositor), 0.289 (DCC) 
• R-Value Observed: 
  0.289 (Depositor) 

Literature

Molecular features of the UNC-45 chaperone critical for binding and folding muscle myosin.

Hellerschmied, D., Lehner, A., Franicevic, N., Arnese, R., Johnson, C., Vogel, A., Meinhart, A., Kurzbauer, R., Deszcz, L., Gazda, L., Geeves, M., Clausen, T.

(2019) Nat Commun 10: 4781-4781

• PubMed: 31636255 
• DOI: https://doi.org/10.1038/s41467-019-12667-8
• Primary Citation Related Structures: 
  6QDJ, 6QDK, 6QDL, 6QDM


• PubMed Abstract: 
  

  Myosin is a motor protein that is essential for a variety of processes ranging from intracellular transport to muscle contraction. Folding and assembly of myosin relies on a specific chaperone, UNC-45. To address its substrate-targeting mechanism, we reconstitute the interplay between Caenorhabditis elegans UNC-45 and muscle myosin MHC-B in insect cells. In addition to providing a cellular chaperone assay, the established system enabled us to produce large amounts of functional muscle myosin, as evidenced by a biochemical and structural characterization, and to directly monitor substrate binding to UNC-45. Data from in vitro and cellular chaperone assays, together with crystal structures of binding-deficient UNC-45 mutants, highlight the importance of utilizing a flexible myosin-binding domain. This so-called UCS domain can adopt discrete conformations to efficiently bind and fold substrate. Moreover, our data uncover the molecular basis of temperature-sensitive UNC-45 mutations underlying one of the most prominent motility defects in C. elegans.

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Organizational Affiliation: 
• Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria. [e-mail].
Faculty of Biology, Center of Medical Biotechnology, University Duisburg-Essen, Essen, Germany. [e-mail].
Vienna BioCenter Facilities, Vienna, Austria.
Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria.
School of Biosciences, University of Kent, Canterbury, UK.
Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria. [e-mail].
Medical University Vienna, Vienna, Austria. [e-mail].

Biological Assembly 1  

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

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

Macromolecule Content 

• Total Structure Weight: 107.85 kDa 
• Atom Count: 6,848 
• Modeled Residue Count: 882 
• Deposited Residue Count: 964 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
UNC-45,UNC-45	A	964	Caenorhabditis elegans	Mutation(s): 1  Gene Names: unc-45, CELE_F30H5.1, F30H5.1
UniProt
Find proteins for G5EG62 (Caenorhabditis elegans) Explore G5EG62  Go to UniProtKB:  G5EG62

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET
UNK	A	L-PEPTIDE LINKING	C4 H9 N O2		--

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free:  0.319 (Depositor), 0.294 (DCC) 
• R-Value Work:  0.287 (Depositor), 0.289 (DCC) 
• R-Value Observed: 0.289 (Depositor) 

Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 86.91	α = 90
b = 86.91	β = 90
c = 718.54	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
CNS	refinement
O	model building
SHARP	phasing
XDS	data reduction
SCALA	data scaling

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2019-10-30 
Deposition Author(s): Meinhart, A., Clausen, T., Hellerschmied, D.

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Funding Organization	Location	Grant Number
Austrian Science Fund	Austria	P 22570

Revision History  

• Version 1.0: 2019-10-30
  Type: Initial release
  
• Version 1.1: 2024-10-16
  Changes: Data collection, Database references, Structure summary