Diverse modes of synaptic signaling, regulation, and plasticity distinguish classes of C. elegans glutamatergic neurons
Abstract
Synaptic vesicle release properties vary between neuronal cell types, but in most cases the molecular basis of this heterogeneity is unknown. Here, we compare in vivo synaptic properties of two neuronal classes in the C. elegans central nervous system, using VGLUT-pHluorin to monitor synaptic vesicle exocytosis and retrieval in intact animals. We show that the glutamatergic sensory neurons AWCON and ASH have distinct synaptic dynamics associated with tonic and phasic synaptic properties, respectively. Exocytosis in ASH and AWCON is differentially affected by SNARE-complex regulators that are present in both neurons: phasic ASH release is strongly dependent on UNC-13, whereas tonic AWCON release relies upon UNC-18 and on the protein kinase C homolog PKC-1. Strong stimuli that elicit high calcium levels increase exocytosis and retrieval rates in AWCON, generating distinct tonic and evoked synaptic modes. These results highlight the differential deployment of shared presynaptic proteins in neuronal cell type-specific functions.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Cornelia I Bargmann
Jensam Foundation
- Cornelia I Bargmann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Graeme W Davis, University of California, San Francisco, United States
Version history
- Received: August 14, 2017
- Accepted: November 20, 2017
- Accepted Manuscript published: November 21, 2017 (version 1)
- Version of Record published: November 28, 2017 (version 2)
Copyright
© 2017, Ventimiglia & Bargmann
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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