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Updated: Jun 10, 2026

Live Imaging of Synaptic Vesicle Recycling in the Neuromuscular Junction of Dissected Larval Zebrafish
Published on: February 7, 2025
Distinct roles for two synaptotagmin isoforms in synchronous and asynchronous transmitter release at zebrafish
Hua Wen1, Michael W Linhoff, Matthew J McGinley
1Vollum Institute, Oregon Health and Sciences University, Portland, OR 97239, USA.
Abstract:
An obligatory role for the calcium sensor synaptotagmins in stimulus-coupled release of neurotransmitter is well established, but a role for synaptotagmin isoform involvement in asynchronous release remains conjecture. We show, at the zebrafish neuromuscular synapse, that two separate synaptotagmins underlie these processes. Specifically, knockdown of synaptotagmin 2 (syt2) reduces synchronous release, whereas knockdown of synaptotagmin 7 (syt7) reduces the asynchronous component of release. The zebrafish neuromuscular junction is unique in having a very small quantal content and a high release probability under conditions of either low-frequency stimulation or high-frequency augmentation. Through these features, we further determined that during the height of shared synchronous and asynchronous transmission these two modes compete for the same release sites.
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