Kiss-and-run, collapse and 'readily retrievable' vesicles
Silvio O Rizzoli1, Reinhard Jahn
1Department of Neurobiology, Max-Planck-Institute for Biophysical Chemistry, 37077 Göttingen, Germany.
Traffic (Copenhagen, Denmark)
|July 25, 2007
Summary
Synaptic vesicle recycling occurs via kiss-and-run or full fusion. Both models demonstrate high fidelity, with readily retrievable vesicles enabling fast endocytosis for full fusion, minimizing efficiency differences.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Synaptic vesicle recycling is crucial for neurotransmission.
- Two models, kiss-and-run and full fusion, are debated for vesicle recycling mechanisms.
- Kiss-and-run was hypothesized to be faster and more faithful than full fusion.
Purpose of the Study:
- To review recent evidence supporting both synaptic vesicle recycling models.
- To compare the efficiency and fidelity of kiss-and-run versus full fusion.
- To elucidate the role of readily retrievable vesicles in synaptic vesicle recycling.
Main Methods:
- Literature review of experimental evidence for synaptic vesicle recycling models.
- Analysis of data comparing kiss-and-run and full fusion mechanisms.
- Conceptual analysis of vesicle fusion pore dynamics and endocytosis.
Main Results:
- Both kiss-and-run and full fusion mechanisms support high-fidelity vesicle recycling.
- Full fusion, aided by readily retrievable vesicles, can trigger rapid endocytosis.
- Efficiency differences between the two models are less pronounced than previously thought.
Conclusions:
- Both kiss-and-run and full fusion are viable and high-fidelity mechanisms for synaptic vesicle recycling.
- The presence of readily retrievable vesicles enhances the speed of full fusion-mediated endocytosis.
- The debate on the efficiency of synaptic vesicle recycling models is nuanced by the interplay of different mechanisms.
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