Neuron hemilineages provide the functional ground plan for the Drosophila ventral nervous system

  1. Robin M Harris
  2. Barret D Pfeiffer
  3. Gerald M Rubin
  4. James W Truman  Is a corresponding author
  1. Janelia Research Campus, Howard Hughes Medical Institute, United States

Abstract

Drosophila central neurons arise from neuroblasts that generate neurons in a pair-wise fashion, with the two daughters providing the basis for distinct A and B hemilineage groups. Thirty three postembryonically-born hemilineages contribute over 90% of the neurons in each thoracic hemisegment. We devised genetic approaches to define the anatomy of most of these hemilineages and to assessed their functional roles using the heat-sensitive channel dTRPA1. The simplest hemilineages contained local interneurons and their activation caused tonic or phasic leg movements lacking interlimb coordination. The next level was hemilineages of similar projection cells that drove intersegmentally coordinated behaviors such as walking. The highest level involved hemilineages whose activation elicited complex behaviors such as takeoff. These activation phenotypes indicate that the hemilineages vary in their behavioral roles with some contributing to local networks for sensorimotor processing and others having higher order functions of coordinating these local networks into complex behavior.

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Author details

  1. Robin M Harris

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Barret D Pfeiffer

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Gerald M Rubin

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. James W Truman

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    trumanj@janelia.hhmi.org
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Harris 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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  1. Robin M Harris
  2. Barret D Pfeiffer
  3. Gerald M Rubin
  4. James W Truman
(2015)
Neuron hemilineages provide the functional ground plan for the Drosophila ventral nervous system
eLife 4:e04493.
https://doi.org/10.7554/eLife.04493

Share this article

https://doi.org/10.7554/eLife.04493

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