A locomotor neural circuit persists and functions similarly in larvae and adult Drosophila

  1. Kristen Lee
  2. Chris Q Doe  Is a corresponding author
  1. Virginia Commonwealth University, United States
  2. Howard Hughes Medical Institute, University of Oregon, United States

Abstract

Individual neurons can undergo drastic structural changes, known as neuronal remodeling or structural plasticity. One example of this is in response to hormones, such as during puberty in mammals or metamorphosis in insects. However, in each of these examples it remains unclear whether the remodeled neuron resumes prior patterns of connectivity, and if so, whether the persistent circuits drive similar behaviors. Here, we utilize a well-characterized neural circuit in the Drosophila larva: the Moonwalking Descending Neuron (MDN) circuit. We previously showed that larval MDN induces backward crawling, and synapses onto the Pair1 interneuron to inhibit forward crawling (Carreira-Rosario et al., 2018). MDN is remodeled during metamorphosis and regulates backward walking in the adult fly. We investigated whether Pair1 is remodeled during metamorphosis and functions within the MDN circuit during adulthood. We assayed morphology and molecular markers to demonstrate that Pair1 is remodeled during metamorphosis and persists in the adult fly. MDN-Pair1 connectivity is lost during early pupal stages, when both neurons are severely pruned back, but connectivity is re-established at mid-pupal stages and persist into the adult. In the adult, optogenetic activation of Pair1 resulted in arrest of forward locomotion, similar to what is observed in larvae. Thus, the MDN-Pair1 neurons are an interneuronal circuit - a pair of synaptically connected interneurons – that is re-established during metamorphosis, yet generates similar locomotor behavior at both larval and adult stages.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Kristen Lee

    Virginia Commonwealth University, Richmond, United States
    Competing interests
    No competing interests declared.
  2. Chris Q Doe

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    For correspondence
    cdoe@uoregon.edu
    Competing interests
    Chris Q Doe, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5980-8029

Funding

Howard Hughes Medical Institute

  • Chris Q Doe

National Institutes of Health (HD27056)

  • Kristen Lee

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Ronald L Calabrese, Emory University, United States

Version history

  1. Preprint posted: April 27, 2021 (view preprint)
  2. Received: April 27, 2021
  3. Accepted: July 13, 2021
  4. Accepted Manuscript published: July 14, 2021 (version 1)
  5. Accepted Manuscript updated: July 15, 2021 (version 2)
  6. Version of Record published: July 22, 2021 (version 3)

Copyright

© 2021, Lee & Doe

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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  1. Kristen Lee
  2. Chris Q Doe
(2021)
A locomotor neural circuit persists and functions similarly in larvae and adult Drosophila
eLife 10:e69767.
https://doi.org/10.7554/eLife.69767

Share this article

https://doi.org/10.7554/eLife.69767

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