3C98

Revised structure of the munc18a-syntaxin1 complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.208 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Munc18a controls SNARE assembly through its interaction with the syntaxin N-peptide

Burkhardt, P.Hattendorf, D.A.Weis, W.I.Fasshauer, D.

(2008) EMBO J 27: 923-933

  • DOI: 10.1038/emboj.2008.37
  • Primary Citation of Related Structures:  
    3C98

  • PubMed Abstract: 
  • Sec1/Munc18-like (SM) proteins functionally interact with SNARE proteins in vesicular fusion. Despite their high sequence conservation, structurally disparate binding modes for SM proteins with syntaxins have been observed. Several SM proteins appear to ...

    Sec1/Munc18-like (SM) proteins functionally interact with SNARE proteins in vesicular fusion. Despite their high sequence conservation, structurally disparate binding modes for SM proteins with syntaxins have been observed. Several SM proteins appear to bind only to a short peptide present at the N terminus of syntaxin, designated the N-peptide, while Munc18a binds to a 'closed' conformation formed by the remaining portion of syntaxin 1a. Here, we show that the syntaxin 16 N-peptide binds to the SM protein Vps45, but the remainder of syntaxin 16 strongly enhances the affinity of the interaction. Likewise, the N-peptide of syntaxin 1a serves as a second binding site in the Munc18a/syntaxin 1a complex. When the syntaxin 1a N-peptide is bound to Munc18a, SNARE complex formation is blocked. Removal of the N-peptide enables binding of syntaxin 1a to its partner SNARE SNAP-25, while still bound to Munc18a. This suggests that Munc18a controls the accessibility of syntaxin 1a to its partners, a role that might be common to all SM proteins.


    Related Citations: 
    • Three-dimensional structure of the neuronal-Sec1-syntaxin 1a complex
      Misura, K.M., Scheller, R.H., Weis, W.I.
      (2000) Nature 404: 355

    Organizational Affiliation

    Research Group Structural Biochemistry, Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Syntaxin-binding protein 1 A606Rattus norvegicusMutation(s): 0 
Gene Names: Stxbp1Unc18a
Find proteins for P61765 (Rattus norvegicus)
Explore P61765 
Go to UniProtKB:  P61765
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Syntaxin-1A B279Rattus norvegicusMutation(s): 0 
Gene Names: Stx1aSap
Find proteins for P32851 (Rattus norvegicus)
Explore P32851 
Go to UniProtKB:  P32851
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.203 
  • R-Value Observed: 0.208 
  • Space Group: P 4 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 158.07α = 90
b = 158.07β = 90
c = 81.45γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
ADSCdata collection
DENZOdata reduction
SCALEPACKdata scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-03-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance