1. Neuroscience
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Building a functional connectome of the Drosophila central complex

  1. Romain Franconville  Is a corresponding author
  2. Celia Beron
  3. Vivek Jayaraman  Is a corresponding author
  1. Howard Hughes Medical Institute, United States
Research Article
  • Cited 42
  • Views 4,773
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Cite this article as: eLife 2018;7:e37017 doi: 10.7554/eLife.37017


The central complex is a highly conserved insect brain region composed of morphologically stereotyped neurons that arborize in distinctively shaped substructures. The region is implicated in a wide range of behaviors and several modeling studies have explored its circuit computations. Most studies have relied on assumptions about connectivity between neurons based on their overlap in light microscopy images. Here, we present an extensive functional connectome of Drosophila melanogaster's central complex at cell-type resolution. Using simultaneous optogenetic stimulation, calcium imaging and pharmacology, we tested the connectivity between 70 presynaptic-to-postsynaptic cell-type pairs. We identi1ed numerous inputs to the central complex, but only a small number of output channels. Additionally, the connectivity of this highly recurrent circuit appears to be sparser than anticipated from light microscopy images. Finally, the connectivity matrix highlights the potentially critical role of a class of bottleneck interneurons. All data is provided for interactive exploration on a website.

Data availability

All the data generated or analyzed during this study is freely available for exploration at:https://romainfr.github.io/CX-Functional-Website/All code and data are available at:https://osf.io/vsa3z/

The following data sets were generated
    1. Franconville R
    (2018) Central complex functional connectivity
    DOI 10.17605/OSF.IO/VSA3Z | ARK c7605/osf.io/vsa3z.

Article and author information

Author details

  1. Romain Franconville

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4440-7297
  2. Celia Beron

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

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3680-7378


Howard Hughes Medical Institute

  • Romain Franconville
  • Celia Beron
  • Vivek Jayaraman

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

Reviewing Editor

  1. Kristin Scott, University of California, Berkeley, Berkeley, United States

Publication history

  1. Received: March 27, 2018
  2. Accepted: August 14, 2018
  3. Accepted Manuscript published: August 20, 2018 (version 1)
  4. Version of Record published: September 21, 2018 (version 2)


© 2018, Franconville 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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Further reading

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