Short-term plasticity at cerebellar granule cell to molecular layer interneuron synapses expands information processing
Information processing by cerebellar molecular layer interneurons (MLIs) plays a crucial role in motor behavior. MLI recruitment is tightly controlled by the profile of short-term plasticity (STP) at granule cell (GC)-MLI synapses. While GCs are the most numerous neurons in the brain, STP diversity at GC-MLI synapses is poorly documented. Here, we studied how single MLIs are recruited by their distinct GC inputs during burst firing. Using slice recordings at individual GC-MLI synapses of mice, we revealed four classes of connections segregated by their STP profile. Each class differentially drives MLI recruitment. We show that GC synaptic diversity is underlain by heterogeneous expression of synapsin II, a key actor of STP and that GC terminals devoid of synapsin II are associated with slow MLI recruitment. Our study reveals that molecular, structural and functional diversity across GC terminals provides a mechanism to expand the coding range of MLIs.
Article and author information
Agence Nationale de la Recherche (ANR-2015CeMod)
- Philippe Isope
Fondation pour la Recherche Médicale (DEQ20140329514)
- Philippe Isope
Ministère de l'Education Nationale, de l'Enseignement Superieur et de la Recherche
- Kevin Dorgans
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: This study was carried out in strict accordance with the national and international laws for laboratory animal welfare and experimentation and was approved in advance by the Ethics Committee of Strasbourg (CREMEAS; CEEA35; agreement number/reference protocol: APAFIS#4354-20 16030212155187 v3).
- Indira M Raman, Northwestern University, United States
- Received: September 11, 2018
- Accepted: May 11, 2019
- Accepted Manuscript published: May 13, 2019 (version 1)
- Version of Record published: May 23, 2019 (version 2)
© 2019, Dorgans 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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