Spatial readout of visual looming in the central brain of Drosophila
- University College London, United Kingdom
- Janelia Research Campus, Howard Hughes Medical Institute, United States
- Howard Hughes Medical Institute, United States
- Cornell University, United States
- University of Vermont, United States
Abstract
Visual systems can exploit spatial correlations in the visual scene by using retinotopy. However, retinotopy is often lost, such as when visual pathways are integrated with other sensory modalities. How is spatial information processed outside of strictly visual brain areas? Here, we focused on visual looming responsive LC6 cells in Drosophila, a population whose dendrites collectively cover the visual field, but whose axons form a single glomerulus-a structure without obvious retinotopic organization-in the central brain. We identified multiple cell types downstream of LC6 in the glomerulus and found that they more strongly respond to looming in different portions of the visual field, unexpectedly preserving spatial information. Through EM reconstruction of all LC6 synaptic inputs to the glomerulus, we found that LC6 and downstream cell types form circuits within the glomerulus that enable spatial readout of visual features and contralateral suppression-mechanisms that transform visual information for behavioral control.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 3, 5 and 6 along with analysis code (https://github.com/reiserlab/LC6downstream).All reconstructed neurons described in the manuscript will be shortly available at https://fafb.catmaid.virtualflybrain.org/
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Aljoscha Nern
- Arthur Zhao
- Edward M Rogers
- Allan Wong
- Mathew D Isaacson
- Davi Bock
- Gerald M Rubin
- Michael B Reiser
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Claude Desplan, New York University, United States
Version history
- Received: April 8, 2020
- Accepted: November 17, 2020
- Accepted Manuscript published: November 18, 2020 (version 1)
- Version of Record published: December 16, 2020 (version 2)
Copyright
© 2020, Morimoto 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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Spatial readout of visual looming in the central brain of Drosophila
eLife 9:e57685.
https://doi.org/10.7554/eLife.57685
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