Frequency-dependent mobilization of heterogeneous pools of synaptic vesicles shapes presynaptic plasticity
Abstract
The segregation of the readily releasable pool of synaptic vesicles (RRP) in sub-pools that are differentially poised for exocytosis shapes short-term plasticity. However, the frequency-dependent mobilization of these sub-pools is poorly understood. Using slice recordings and modeling of synaptic activity at cerebellar granule cell to Purkinje cell synapses of mice, we describe two sub-pools in the RRP that can be differentially recruited upon ultrafast changes in the stimulation frequency. We show that at low frequency stimulations, a first sub-pool is gradually silenced, leading to full blockage of synaptic transmission. Conversely, a second pool of synaptic vesicles that cannot be released by a single stimulus is recruited within milliseconds by high-frequency stimulation and support an ultrafast recovery of neurotransmitter release after low-frequency depression. This frequency-dependent mobilization or silencing of sub-pools in the RRP in terminals of granule cells may play a role in the filtering of sensorimotor information in the cerebellum.
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Author details
Funding
Agence Nationale de la Recherche (ANR-2010-JCJC-1403-1 MicroCer)
- Philippe Isope
Fondation pour la Recherche Médicale (DEQ20140329514)
- Philippe Isope
Centre National de la Recherche Scientifique
- Philippe Isope
Université de Strasbourg
- Philippe Isope
INTERREG IV Rhin superieur (FEDER # A31)
- Philippe Isope
Deutsche Forschungsgemeinschaft (SCHM1838)
- Hartmut Schmidt
Agence Nationale de la Recherche (ANR15-37-CE37-0001-01 CeModR)
- Philippe Isope
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Inna Slutsky, Tel Aviv University, Israel
Ethics
Animal experimentation: All experimental protocols are in accordance with European and French guidelines for animal experimentation and have been approved by the Bas-Rhin veterinary office, Strasbourg, France (authorization number A 67-311 to FD)
Version history
- Received: May 30, 2017
- Accepted: October 6, 2017
- Accepted Manuscript published: October 9, 2017 (version 1)
- Version of Record published: October 19, 2017 (version 2)
Copyright
© 2017, Doussau et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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