2XHE

Crystal structure of the Unc18-syntaxin 1 complex from Monosiga brevicollis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.188 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Primordial Neurosecretory Apparatus Identified in the Choanoflagellate Monosiga Brevicollis.

Burkhardt, P.Stegmann, C.M.Cooper, B.Kloepper, T.H.Imig, C.Varoqueaux, F.Wahl, M.C.Fasshauer, D.

(2011) Proc.Natl.Acad.Sci.USA 108: 15264

  • DOI: 10.1073/pnas.1106189108

  • PubMed Abstract: 
  • SNARE protein-driven secretion of neurotransmitters from synaptic vesicles is at the center of neuronal communication. In the absence of the cytosolic protein Munc18-1, synaptic secretion comes to a halt. Although it is believed that Munc18-1 orchest ...

    SNARE protein-driven secretion of neurotransmitters from synaptic vesicles is at the center of neuronal communication. In the absence of the cytosolic protein Munc18-1, synaptic secretion comes to a halt. Although it is believed that Munc18-1 orchestrates SNARE complexes, its mode of action is still a matter of debate. In particular, it has been challenging to clarify the role of a tight Munc18/syntaxin 1 complex, because this interaction interferes strongly with syntaxin's ability to form a SNARE complex. In this complex, two regions of syntaxin, the N-peptide and the remainder in closed conformation, bind to Munc18 simultaneously. Until now, this binary complex has been reported for neuronal tissues only, leading to the hypothesis that it might be a specialization of the neuronal secretion apparatus. Here we aimed, by comparing the core secretion machinery of the unicellular choanoflagellate Monosiga brevicollis with that of animals, to reconstruct the ancestral function of the Munc18/syntaxin1 complex. We found that the Munc18/syntaxin 1 complex from M. brevicollis is structurally and functionally highly similar to the vertebrate complex, suggesting that it constitutes a fundamental step in the reaction pathway toward SNARE assembly. We thus propose that the primordial secretion machinery of the common ancestor of choanoflagellates and animals has been co-opted for synaptic roles during the rise of animals.


    Organizational Affiliation

    Research Group Structural Biochemistry, Department of Neurobiology, and Research Group X-Ray Crystallography, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
UNC18
A
650Monosiga brevicollisMutation(s): 0 
Find proteins for A9V0L3 (Monosiga brevicollis)
Go to UniProtKB:  A9V0L3
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
SYNTAXIN1
B
279Monosiga brevicollisMutation(s): 0 
Find proteins for A9UTG5 (Monosiga brevicollis)
Go to UniProtKB:  A9UTG5
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.250 
  • R-Value Work: 0.188 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 146.200α = 90.00
b = 146.200β = 90.00
c = 214.861γ = 120.00
Software Package:
Software NamePurpose
XDSdata scaling
PHASERphasing
XDSdata reduction
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-06-29
    Type: Initial release
  • Version 1.1: 2012-03-14
    Type: Database references, Version format compliance