A genetic basis for molecular asymmetry at vertebrate electrical synapses
- Univeristy of Oregon, United States
- Fred Hutchinson Cancer Research Center, United States
- University of Pennsylvania Perelman School of Medicine, United States
- McGovern Medical School, University of Texas Health Sciences Center at Houston, United States
Abstract
Neural network function is based upon the patterns and types of connections made between neurons. Neuronal synapses are adhesions specialized for communication and they come in two types, chemical and electrical. Communication at chemical synapses occurs via neurotransmitter release whereas electrical synapses utilize gap junctions for direct ionic and metabolic coupling. Electrical synapses are often viewed as symmetrical structures, with the same components making both sides of the gap junction. By contrast, we show that a broad set of electrical synapses in zebrafish, Danio rerio, require two gap-junction-forming Connexins for formation and function. We find that one Connexin functions presynaptically while the other functions postsynaptically in forming the channels. We also show that these synapses are required for the speed and coordination of escape responses. Our data identify a genetic basis for molecular asymmetry at vertebrate electrical synapses and show they are required for appropriate behavioral performance.
Data availability
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Dis2 RNA-seq wildtype and mutantPublicly available at the NCBI Sequence Read Archive (accession no: PRJNA172016).
Article and author information
Author details
Funding
National Institute of Neurological Disorders and Stroke (F32NS074839)
- Adam C Miller
National Institute of Mental Health (R01MH109498)
- Michael Granato
National Eye Institute (R01EY012857)
- John O'Brien
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD076585)
- Cecilia B Moens
National Institute of Neurological Disorders and Stroke (R21NS076950)
- Cecilia B Moens
National Institute of Neurological Disorders and Stroke (K99/R00NS085035)
- Adam C Miller
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animals were raised in an Institutional Animal Care and Use Committee (IACUC)-approvedfacility at the Fred Hutchinson Cancer Research Center (Study ID 50552, Submittal ID 7237, IRO #1392).
Copyright
© 2017, Miller 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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A genetic basis for molecular asymmetry at vertebrate electrical synapses
eLife 6:e25364.
https://doi.org/10.7554/eLife.25364
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