Abstract

The SNARE complex assembles from vesicular Synaptobrevin-2 as well as Syntaxin-1 and SNAP25 both anchored to the presynaptic membrane. It mediates fusion of synaptic vesicles with the presynaptic plasma membrane resulting in exocytosis of neurotransmitters. While the general sequence of SNARE complex formation is well-established, our knowledge on possible intermediates and stable off-pathway complexes is incomplete. We, therefore, follow the stepwise assembly of the SNARE complex and target individual SNAREs, binary sub-complexes, the ternary SNARE complex as well as interactions with Complexin-1. Using native mass spectrometry, we identify the stoichiometry of sub-complexes and monitor oligomerisation of various assemblies. Importantly, we find that interactions with Complexin-1 reduce multimerisation of the ternary SNARE complex. Chemical cross-linking provides detailed insights into these interactions suggesting a role for membrane fusion. In summary, we unravel the stoichiometry of intermediates and off-pathway complexes and compile a road map of SNARE complex assembly including regulation by Complexin-1.

Chemical cross-linking and native mass spectrometry aid the thorough investigation of complex formation and multimerisation of synaptic vesicle fusion-mediating SNARE complex, including the role of complexin-1 in its assembly.

Details

Title
Mass spectrometry uncovers intermediates and off-pathway complexes for SNARE complex assembly
Author
Hesselbarth, Julia 1 ; Schmidt, Carla 1   VIAFID ORCID Logo 

 Martin Luther University Halle-Wittenberg, Interdisciplinary Research Centre HALOmem, Charles Tanford Protein Centre, Institute of Biochemistry and Biotechnology, Halle, Germany (GRID:grid.9018.0) (ISNI:0000 0001 0679 2801); Johannes Gutenberg University Mainz, Department of Chemistry – Biochemistry, Biocenter II, Mainz, Germany (GRID:grid.5802.f) (ISNI:0000 0001 1941 7111) 
Pages
198
Publication year
2023
Publication date
2023
Publisher
Nature Publishing Group
e-ISSN
23993642
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2778169461
Copyright
© The Author(s) 2023. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.