2KDU

Structural basis of the Munc13-1/Ca2+-Calmodulin interaction: A novel 1-26 calmodulin binding motif with a bipartite binding mode


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Modular architecture of Munc13/calmodulin complexes: dual regulation by Ca2+ and possible function in short-term synaptic plasticity.

Rodriguez-Castaneda, F.Maestre-Martinez, M.Coudevylle, N.Dimova, K.Junge, H.Lipstein, N.Lee, D.Becker, S.Brose, N.Jahn, O.Carlomagno, T.Griesinger, C.

(2010) EMBO J 29: 680-691

  • DOI: https://doi.org/10.1038/emboj.2009.373
  • Primary Citation of Related Structures:  
    2KDU

  • PubMed Abstract: 

    Ca(2+) signalling in neurons through calmodulin (CaM) has a prominent function in regulating synaptic vesicle trafficking, transport, and fusion. Importantly, Ca(2+)-CaM binds a conserved region in the priming proteins Munc13-1 and ubMunc13-2 and thus regulates synaptic neurotransmitter release in neurons in response to residual Ca(2+) signals. We solved the structure of Ca(2+)(4)-CaM in complex with the CaM-binding domain of Munc13-1, which features a novel 1-5-8-26 CaM-binding motif with two separated mobile structural modules, each involving a CaM domain. Photoaffinity labelling data reveal the same modular architecture in the complex with the ubMunc13-2 isoform. The N-module can be dissociated with EGTA to form the half-loaded Munc13/Ca(2+)(2)-CaM complex. The Ca(2+) regulation of these Munc13 isoforms can therefore be explained by the modular nature of the Munc13/Ca(2+)-CaM interactions, where the C-module provides a high-affinity interaction activated at nanomolar [Ca(2+)](i), whereas the N-module acts as a sensor at micromolar [Ca(2+)](i). This Ca(2+)/CaM-binding mode of Munc13 likely constitutes a key molecular correlate of the characteristic Ca(2+)-dependent modulation of short-term synaptic plasticity.


  • Organizational Affiliation

    Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Calmodulin148Xenopus laevisMutation(s): 0 
Gene Names: calm1calm2
UniProt
Find proteins for P0DP33 (Xenopus laevis)
Explore P0DP33 
Go to UniProtKB:  P0DP33
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0DP33
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Protein unc-13 homolog A36Rattus norvegicusMutation(s): 0 
Gene Names: Unc13a
UniProt
Find proteins for Q62768 (Rattus norvegicus)
Explore Q62768 
Go to UniProtKB:  Q62768
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ62768
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report



Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2009-12-15
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2022-03-16
    Changes: Data collection, Database references, Derived calculations
  • Version 1.3: 2024-05-22
    Changes: Data collection