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Updated: Jul 5, 2026
08:55
Visualizing Intracellular SNARE Trafficking by Fluorescence Lifetime Imaging Microscopy
Published on: December 29, 2017
For better or for worse: complexins regulate SNARE function and vesicle fusion.
1Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany. brose@em.mpg.de
Traffic (Copenhagen, Denmark)
|May 1, 2008
Summary
Complexins, regulators of SNARE-mediated fusion, have contradictory roles in vesicle fusion. This review synthesizes data to propose a model explaining both their facilitatory and inhibitory functions in synaptic vesicle release.
Area of Science:
- Neuroscience
- Molecular Biology
- Cell Biology
Background:
- SNARE-mediated synaptic vesicle fusion is crucial for neurotransmission.
- Regulatory proteins, like complexins, modulate the speed and Ca(2+) sensitivity of this fusion process.
- Complexins bind to SNARE complexes, comprising synaptobrevin, syntaxin, and SNAP-25.
Purpose of the Study:
- To review and reconcile conflicting data on complexin function in SNARE-mediated fusion.
- To propose a unified model for complexin roles in synaptic vesicle exocytosis.
Main Methods:
- Literature review of biochemical in vitro experiments.
- Analysis of in vivo studies on vertebrate complexins.
Main Results:
- Biochemical and in vivo studies present apparently contradictory findings on complexin activity.
- Evidence suggests complexins can both facilitate and inhibit SNARE-mediated fusion.
- Controversy exists regarding whether complexins promote or hinder vesicle fusion.
Conclusions:
- A comprehensive model is needed to integrate diverse findings on complexin function.
- Complexins likely play dual roles, facilitating and inhibiting SNARE-mediated vesicle fusion.
- Further research is required to fully elucidate the complexin regulatory mechanism in synaptic transmission.
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