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Updated: Jun 20, 2026

An Optical Assay for Synaptic Vesicle Recycling in Cultured Neurons Overexpressing Presynaptic Proteins
Published on: June 26, 2018
The origin and evolution of synapses
1Wellcome Trust Sanger Institute, Hinxton, Cambridge CB101SA, UK.
Abstract:
Understanding the evolutionary origins of behaviour is a central aim in the study of biology and may lead to insights into human disorders. Synaptic transmission is observed in a wide range of invertebrate and vertebrate organisms and underlies their behaviour. Proteomic studies of the molecular components of the highly complex mammalian postsynaptic machinery point to an ancestral molecular machinery in unicellular organisms--the protosynapse--that existed before the evolution of metazoans and neurons, and hence challenges existing views on the origins of the brain. The phylogeny of the molecular components of the synapse provides a new model for studying synapse diversity and complexity, and their implications for brain evolution.
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The presynaptic neuron fires an action potential that...
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Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
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