Pupal behavior emerges from unstructured muscle activity in response to neuromodulation in Drosophila
Abstract
Identifying neural substrates of behavior requires defining actions in terms that map onto brain activity. Brain and muscle activity naturally correlate via the output of motor neurons, but apart from simple movements it has been difficult to define behavior in terms of muscle contractions. By mapping the musculature of the pupal fruit fly and comprehensively imaging muscle activation at single cell resolution, we here describe a multiphasic behavioral sequence in Drosophila. Our characterization identifies a previously undescribed behavioral phase and permits extraction of major movements by a convolutional neural network. We deconstruct movements into a syllabary of co-active muscles and identify specific syllables that are sensitive to neuromodulatory manipulations. We find that muscle activity shows considerable variability, with sequential increases in stereotypy dependent upon neuromodulation. Our work provides a platform for studying whole-animal behavior, quantifying its variability across multiple spatiotemporal scales, and analyzing its neuromodulatory regulation at cellular resolution.
Data availability
The source data for the figures and tables in this study are available at figshare (https://figshare.com/collections/Pupal_behavior_emerges_from_unstructured_muscle_activity_in_response_to_neuromodulation_in_Drosophila/5489637) and computer code is posted to https://github.com/BenjaminHWhite.
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Funding
National Institute of General Medical Sciences (F12-GM117582)
- Amicia D Elliott
National Institute of Mental Health (ZIA-MH002800)
- Benjamin H White
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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