Fusion of a synaptic vesicle with the pre-synaptic membrane

Neurones communicate with their target cells primarily through the regulated fusion of synaptic vesicles with the nerve terminal membrane and subsequent release of chemical neurotransmitter into the synaptic cleft. Synaptic vesicles move down the axon and bind to release sites on the pre-synaptic membrane via vesicle-membrane proteins (v-SNARE) and target-membrane proteins (t-SNAREs). This SNARE complex interacts with both NSF (N-ethylmaleimide Sensitive Fusion protein) and SNAP (Soluble NSF Attachment Proteins) to form a fusion complex. Action potential propagation induces calcium influx at the pre-synaptic membrane, which, in addition to ATP hydrolysis by NSF, results in disassembly of the SNARE complex and membrane fusion. Following neurotransmitter release, synaptic vesicle membrane components are recycled via an endocytic process.

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References

Analysis of neurotransmitter release mechanisms. Department of Genome Sciences, University of Washington. http://www.gs.washington.edu/labs/pallanck/research/synaptic.htm Accessed on 15 January 2003.