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Updated: May 23, 2026
10:17
Presynapse Formation Assay Using Presynapse Organizer Beads and “Neuron Ball” Culture
Published on: August 2, 2019
Munc18-1 mutations that strongly impair SNARE-complex binding support normal synaptic transmission.
Marieke Meijer1, Pawel Burkhardt, Heidi de Wit
1Department of Functional Genomics and Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University Amsterdam, The Netherlands.
The EMBO Journal
|March 27, 2012
Summary
Munc18-1 protein is crucial for synaptic transmission. Mutations affecting its binding to Syntaxin1a and SNARE complexes still allow normal vesicle fusion, suggesting Munc18-1 acts early in SNARE complex assembly.
Area of Science:
- Neuroscience
- Molecular Biology
- Cell Biology
Background:
- Synaptic transmission relies on Munc18-1, a Sec1p/Munc18 protein.
- Munc18-1's precise role in fusion machinery and complex assembly remains debated.
Purpose of the Study:
- To investigate the functional role of Munc18-1 during synaptic vesicle fusion.
- To determine if Munc18-1's interaction with Syntaxin1a and SNARE complexes is essential throughout the fusion process.
Main Methods:
- Generated point mutations in Munc18-1 affecting Syntaxin1a and SNARE complex binding.
- Assessed synaptic vesicle docking, priming, fusion, and synaptic plasticity in mutant neurons derived from munc18-1 null mutant mice.
Main Results:
- Mutant Munc18-1 proteins, impaired in binding to Syntaxin1a N-terminus and SNARE complexes, supported normal synaptic vesicle docking, priming, and fusion.
- Synaptic plasticity remained normal in neurons expressing these Munc18-1 mutants.
Conclusions:
- Munc18-1 primarily functions upstream, during or before SNARE complex assembly.
- Munc18-1's sustained association with assembled SNARE complexes is not required for synaptic transmission and plasticity.
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