Sensorimotor pathway controlling stopping behavior during chemotaxis in the Drosophila melanogaster larva
- The Barcelona Institute of Science and Technology, Spain
- Janelia Research Campus, Howard Hughes Medical Institute, United States
- University of California, Santa Barbara, United States
Abstract
Sensory navigation results from coordinated transitions between distinct behavioral programs. During chemotaxis in the Drosophila melanogaster larva, the detection of positive odor gradients extends runs while negative gradients promote stops and turns. This algorithm represents a foundation for the control of sensory navigation across phyla. In the present work, we identified an olfactory descending neuron, PDM-DN, which plays a pivotal role in the organization of stops and turns in response to the detection of graded changes in odor concentrations. Artificial activation of this descending neuron induces deterministic stops followed by the initiation of turning maneuvers through head casts. Using electron microscopy, we reconstructed the main pathway that connects the PDM-DN neuron to the peripheral olfactory system and to the pre-motor circuit responsible for the actuation of forward peristalsis. Our results set the stage for a detailed mechanistic analysis of the sensorimotor conversion of graded olfactory inputs into action selection to perform goal-oriented navigation.
Data availability
Scripts for data analysis, source data files for the behavioral and imaging experiments have been made available on the GitHub account of the Louis lab (https://github.com/LabLouis/eLife2018_PDM-DN).
Article and author information
Author details
Funding
Spanish Ministry of Economy and Competitiveness (BFU2011-26208)
- Ibrahim Tastekin
- Avinash Khandelwal
- David Tadres
- Nico D Fessner
- Matthieu Louis
EU Marie Curie FP7 Programme (ITN-FLiACT)
- Ibrahim Tastekin
- Matthieu Louis
Howard Hughes Medical Institute
- James W Truman
- Marta Zlatic
- Albert Cardona
University of California, Santa Barbara
- David Tadres
- Matthieu Louis
La Caixa International PhD program
- Avinash Khandelwal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Tastekin 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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Sensorimotor pathway controlling stopping behavior during chemotaxis in the Drosophila melanogaster larva
eLife 7:e38740.
https://doi.org/10.7554/eLife.38740
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