Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Predict Membrane 

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Predict Membrane 

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

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 77.47 kDa 
• Atom Count: 4852 
• Modelled Residue Count: 592 
• Deposited Residue Count: 682 
• Unique protein chains: 1

3SWH

Munc13-1, MUN domain, C-terminal module

• PDB DOI: 10.2210/pdb3SWH/pdb

• Classification: EXOCYTOSIS
• Organism(s): Rattus norvegicus
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 
• Membrane Protein: Yes  OPM


• Deposited: 2011-07-13 Released: 2011-11-02 
• Deposition Author(s): Tomchick, D.R., Rizo, J., Li, W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.65 Å
• R-Value Free: 0.302 
• R-Value Work: 0.244 
• R-Value Observed: 0.247 

Literature

The Crystal Structure of a Munc13 C-terminal Module Exhibits a Remarkable Similarity to Vesicle Tethering Factors.

Li, W., Ma, C., Guan, R., Xu, Y., Tomchick, D.R., Rizo, J.

(2011) Structure 19: 1443-1455

• PubMed: 22000513 
• DOI: 10.1016/j.str.2011.07.012
• Primary Citation of Related Structures:  
  3SWH


• PubMed Abstract: 
  

Unc13/Munc13s play a crucial function in neurotransmitter release through their MUN domain, which mediates the transition from the Syntaxin-1/Munc18-1 complex to the SNARE complex. The MUN domain was suggested to be related to tethering factors, but no MUN-domain structure is available to experimentally validate this notion and address key unresolved questions about the interactions and minimal structural unit required for Unc13/Munc13 function. Here we identify an autonomously folded module within the MUN domain (MUN-CD) and show that its crystal structure is remarkably similar to several tethering factors. We also show that the activity in promoting the Syntaxin-1/Munc18-1 to SNARE complex transition is strongly impaired in MUN-CD. These results show that MUN domains and tethering factors indeed belong to the same family and may have a common role in membrane trafficking. We propose a model whereby the MUN-CD module is central for Munc13 function but full activity requires adjacent sequences.

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Related Citations: 

• Munc13 mediates the transition from the closed syntaxin-Munc18 complex to the SNARE complex.
  Ma, C., Li, W., Xu, Y., Rizo, J.
  (2011) Nat Struct Mol Biol 18: 542

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Organizational Affiliation: 

Department of Biochemistry, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein unc-13 homolog A	A, B	341	Rattus norvegicus	Mutation(s): 0  Gene Names: Unc13a, Unc13h1 Membrane Entity: Yes
UniProt
Find proteins for Q62768 (Rattus norvegicus) Explore Q62768  Go to UniProtKB:  Q62768

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.65 Å
• R-Value Free: 0.302 
• R-Value Work: 0.244 
• R-Value Observed: 0.247 
• Space Group: P 4₂

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 160.791	α = 90
b = 160.791	β = 90
c = 42.239	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
HKL-3000	data collection
SHELXS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2011-07-13 
• Released Date: 2011-11-02 
Deposition Author(s): Tomchick, D.R., Rizo, J., Li, W.

Revision History  

• Version 1.0: 2011-11-02
  Type: Initial release
  
• Version 1.1: 2017-07-26
  Changes: Source and taxonomy
• Version 1.2: 2017-11-08
  Changes: Refinement description