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Updated: Jul 7, 2026

Dopamine Release at Individual Presynaptic Terminals Visualized with FFNs
Published on: August 31, 2009
How does synaptotagmin trigger neurotransmitter release?
1Howard Hughes Medical Institute and Department of Physiology, University of Wisconsin, Madison, WI 53706, USA. chapman@physiology.wisc.edu
Abstract:
Neurotransmitter release at synapses involves a highly specialized form of membrane fusion that is triggered by Ca(2+) ions and is optimized for speed. These observations were established decades ago, but only recently have the molecular mechanisms that underlie this process begun to come into view. Here, we summarize findings obtained from genetically modified neurons and neuroendocrine cells, as well as from reconstituted systems, which are beginning to reveal the molecular mechanism by which Ca(2+)-acting on the synaptic vesicle (SV) protein synaptotagmin I (syt)-triggers rapid exocytosis. This work sheds light not only on presynaptic aspects of synaptic transmission, but also on the fundamental problem of membrane fusion, which has remained a puzzle that has yet to be solved in any biological system.
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