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Synaptic vesicle fusion

Abstract

The core of the neurotransmitter release machinery is formed by SNARE complexes, which bring the vesicle and plasma membranes together and are key for fusion, and by Munc18-1, which controls SNARE-complex formation and may also have a direct role in fusion. In addition, SNARE complex assembly is likely orchestrated by Munc13s and RIMs, active-zone proteins that function in vesicle priming and diverse forms of presynaptic plasticity. Synaptotagmin-1 mediates triggering of release by Ca2+, probably through interactions with SNAREs and both membranes, as well as through a tight interplay with complexins. Elucidation of the release mechanism will require a full understanding of the network of interactions among all these proteins and the membranes.

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Figure 1: SNAREs and Munc18-1.
Figure 2: Munc13s and RIMs.
Figure 3: Syntaptotagmin-1 and its coupling to SNAREs and membranes.
Figure 4: Complexins and their coupling to SNAREs and synaptotagmin-1.
Figure 5: Diagram illustrating the notion that Munc18-1, Munc13, complexin and synaptotagmin-1 bind to the SNARE complex.

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Acknowledgements

Work in the authors' laboratories is supported by US National Institutes of Health grants NS40944 and NS37200 (to J.R.) and NS050655 and NS051262 (to C.R.).

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Correspondence to Josep Rizo or Christian Rosenmund.

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Rizo, J., Rosenmund, C. Synaptic vesicle fusion. Nat Struct Mol Biol 15, 665–674 (2008). https://doi.org/10.1038/nsmb.1450

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