Spatiotemporally precise optogenetic activation of sensory neurons in freely walking Drosophila
Abstract
Previous work has characterized how walking Drosophila coordinate the movements of individual limbs (DeAngelis, Zavatone-Veth, and Clark, 2019). To understand the circuit basis of this coordination, one must characterize how sensory feedback from each limb affects walking behavior. However, it has remained difficult to manipulate neural activity in individual limbs of freely moving animals. Here, we demonstrate a simple method for optogenetic stimulation with body side-, body segment-, and limb-specificity that does not require real-time tracking. Instead, we activate at random, precise locations in time and space and use post hoc analysis to determine behavioral responses to specific activations. Using this method, we have characterized limb coordination and walking behavior in response to transient activation of mechanosensitive bristle neurons and sweet-sensing chemoreceptor neurons. Our findings reveal that activating these neurons has opposite effects on turning, and that activations in different limbs and body regions produce distinct behaviors.
Data availability
Source data were deposited on Dryad: https://doi.org/10.5061/dryad.nzs7h44nk.Analysis code is available here: https://github.com/ClarkLabCode/FlyLimbOptoCode.
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Data from: Spatiotemporally precise optogenetic activation of sensory neurons in freely walking <em>Drosophila</em>Dryad Digital Repository, 10.5061/dryad.nzs7h44nk.
Article and author information
Author details
Funding
National Institutes of Health (EY026555)
- Brian D DeAngelis
- Damon A Clark
National Institutes of Health (EY026878)
- Brian D DeAngelis
- Damon A Clark
Chicago Community Trust (Searle Scholar Award)
- Damon A Clark
Alfred P. Sloan Foundation (Fellowship)
- Damon A Clark
National Science Foundation (GRF)
- Brian D DeAngelis
Smith Family Foundation (Scholar Award)
- Brian D DeAngelis
- Damon A Clark
National Science Foundation (IOS 1558103)
- Jacob A Zavatone-Veth
- Damon A Clark
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, DeAngelis 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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