Structural principles of SNARE complex recognition by the AAA+ protein NSF
- Stanford University, United States
- University of Chicago, United States
Abstract
The recycling of SNARE proteins following complex formation and membrane fusion is an essential process in eukaryotic trafficking. A highly conserved AAA+ protein, NSF (N-ethylmaleimide sensitive factor) and an adaptor protein, SNAP (soluble NSF attachment protein), disassembles the SNARE complex. We report electron-cryomicroscopy structures of the complex of NSF, αSNAP, and the full-length soluble neuronal SNARE complex (composed of syntaxin-1A, synaptobrevin-2, SNAP-25A) in the presence of ATP under non-hydrolyzing conditions at ~3.9 Å resolution. These structures reveal electrostatic interactions by which two αSNAP molecules interface with a specific surface of the SNARE complex. This interaction positions the SNAREs such that the 15 N-terminal residues of SNAP-25A are loaded into the D1 ring pore of NSF via a spiral pattern of interactions between a conserved tyrosine NSF residue and SNAP-25A backbone atoms. This loading process likely precedes ATP hydrolysis. Subsequent ATP hydrolysis then drives complete disassembly.
Data availability
The coordinates and corresponding EM density maps have been deposited in the PDB and EMDB, respectively.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Axel T Brunger
National Institutes of Health
- Axel T Brunger
Helen Hay Whitney Foundation
- K Ian White
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, White et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structural principles of SNARE complex recognition by the AAA+ protein NSF
eLife 7:e38888.
https://doi.org/10.7554/eLife.38888
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