Regulation of subcellular dendritic synapse specificity by axon guidance cues

  1. Emily C Sales
  2. Emily L Heckman
  3. Timothy L Warren
  4. Chris Q Doe  Is a corresponding author
  1. Howard Hughes Medical Institute, University of Oregon, United States

Abstract

Neural circuit assembly occurs with subcellular precision, yet the mechanisms underlying this precision remain largely unknown. Subcellular synaptic specificity could be achieved by molecularly distinct subcellular domains that locally regulate synapse formation, or by axon guidance cues restricting access to one of several acceptable targets. We address these models using two Drosophila neurons: the dbd sensory neuron and the A08a interneuron. In wild-type larvae, dbd synapses with the A08a medial dendrite but not the A08a lateral dendrite. dbd-specific overexpression of the guidance receptors Unc-5 or Robo-2 results in lateralization of the dbd axon, which forms anatomical and functional monosynaptic connections with the A08a lateral dendrite. We conclude that axon guidance cues, not molecularly distinct dendritic arbors, are a major determinant of dbd-A08a subcellular synapse specificity.

Data availability

Code is deposited to the GitHub repository named in the text

The following data sets were generated

Article and author information

Author details

  1. Emily C Sales

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Emily L Heckman

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Timothy L Warren

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4429-4106
  4. Chris Q Doe

    Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, United States
    For correspondence
    cdoe@uoregon.edu
    Competing interests
    The authors declare that no competing interests exist.
    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)

  • Chris Q Doe

National Institutes of Health (T32HD007348)

  • Emily L Heckman

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

Reviewing Editor

  1. Graeme W Davis, University of California, San Francisco, United States

Version history

  1. Received: November 9, 2018
  2. Accepted: April 18, 2019
  3. Accepted Manuscript published: April 23, 2019 (version 1)
  4. Version of Record published: May 3, 2019 (version 2)

Copyright

© 2019, Sales 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. Emily C Sales
  2. Emily L Heckman
  3. Timothy L Warren
  4. Chris Q Doe
(2019)
Regulation of subcellular dendritic synapse specificity by axon guidance cues
eLife 8:e43478.
https://doi.org/10.7554/eLife.43478

Share this article

https://doi.org/10.7554/eLife.43478

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