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Asynchronous release sites align with NMDA receptors in mouse hippocampal synapses.

ABSTRACT: Neurotransmitter is released synchronously and asynchronously following an action potential. Our recent study indicates that the release sites of these two phases are segregated within an active zone, with asynchronous release sites enriched near the center in mouse hippocampal synapses. Here we demonstrate that synchronous and asynchronous release sites are aligned with AMPA receptor and NMDA receptor clusters, respectively. Computational simulations indicate that this spatial and temporal arrangement of release can lead to maximal membrane depolarization through AMPA receptors, alleviating the pore-blocking magnesium leading to greater activation of NMDA receptors. Together, these results suggest that release sites are likely organized to activate NMDA receptors efficiently.

SUBMITTER: Li S

PROVIDER: S-EPMC7846561 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Asynchronous release sites align with NMDA receptors in mouse hippocampal synapses.

Li Shuo S Raychaudhuri Sumana S Lee Stephen Alexander SA Brockmann Marisa M MM Wang Jing J Kusick Grant G Prater Christine C Syed Sarah S Falahati Hanieh H Ramos Raul R Bartol Tomas M TM Hosy Eric E Watanabe Shigeki S

Nature communications 20210129 1

Neurotransmitter is released synchronously and asynchronously following an action potential. Our recent study indicates that the release sites of these two phases are segregated within an active zone, with asynchronous release sites enriched near the center in mouse hippocampal synapses. Here we demonstrate that synchronous and asynchronous release sites are aligned with AMPA receptor and NMDA receptor clusters, respectively. Computational simulations indicate that this spatial and temporal arra ...[more]

PMID: 33514725

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