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Updated: May 13, 2026

Presynaptically Silent Synapses Studied with Light Microscopy
Published on: January 4, 2010
Synapsin II desynchronizes neurotransmitter release at inhibitory synapses by interacting with presynaptic calcium
Lucian Medrihan1, Fabrizia Cesca, Andrea Raimondi
1Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genoa, Italy. lucian.medrihan@iit.it
Abstract:
In the central nervous system, most synapses show a fast mode of neurotransmitter release known as synchronous release followed by a phase of asynchronous release, which extends over tens of milliseconds to seconds. Synapsin II (SYN2) is a member of the multigene synapsin family (SYN1/2/3) of synaptic vesicle phosphoproteins that modulate synaptic transmission and plasticity, and are mutated in epileptic patients. Here we report that inhibitory synapses of the dentate gyrus of Syn II knockout mice display an upregulation of synchronous neurotransmitter release and a concomitant loss of delayed asynchronous release. Syn II promotes γ-aminobutyric acid asynchronous release in a Ca(2+)-dependent manner by a functional interaction with presynaptic Ca(2+) channels, revealing a new role in synaptic transmission for synapsins.
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