1. Developmental Biology
  2. Neuroscience

Robo2 regulates synaptic oxytocin content by affecting actin dynamics

  1. Savani Anbalagan
  2. Janna Blechman
  3. Michael Gliksberg
  4. Ludmila Gordon
  5. Ron Rotkopf
  6. Tali Dadosh
  7. Eyal Shimoni
  8. Gil Levkowitz  Is a corresponding author
  1. Weizmann Institute of Science, Israel
https://doi.org/10.7554/eLife.45650
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Cite this article
  1. Savani Anbalagan
  2. Janna Blechman
  3. Michael Gliksberg
  4. Ludmila Gordon
  5. Ron Rotkopf
  6. Tali Dadosh
  7. Eyal Shimoni
  8. Gil Levkowitz
(2019)
Robo2 regulates synaptic oxytocin content by affecting actin dynamics
eLife 8:e45650.
https://doi.org/10.7554/eLife.45650
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Abstract

The regulation of neuropeptide level at the site of release is essential for proper neurophysiological functions. We focused on a prominent neuropeptide, oxytocin (OXT) in the zebrafish as an in vivo model to visualize and quantify OXT content at the resolution of a single synapse. We found that OXT-loaded synapses were enriched with polymerized actin. Perturbation of actin filaments by either cytochalasin-D or conditional Cofilin expression resulted in decreased synaptic OXT levels. Genetic loss of robo2 or slit3 displayed decreased synaptic OXT content and robo2 mutants displayed reduced mobility of the actin probe Lifeact-EGFP in OXT synapses.Using a novel transgenic reporter allowing real-time monitoring of OXT-loaded vesicles, we showed that robo2 mutants display slower rate of vesicles accumulation. OXT-specific expression of dominant-negative Cdc42, which is a key regulator of actin dynamics and a downstream effector of Robo2, led to a dose-dependent increase in OXT content in WT, and a dampened effect in robo2 mutants. Our results link Slit3-Robo2-Cdc42, which controls local actin dynamics, with the maintenance of synaptic neuropeptide levels.

Data availability

All source data files and codes were uploaded. Source data as summary tables is provided for all graphs and plots shown (Fig. 1E; 2B-E and G-J, 3E-H and J,K,M,N, 4D-F, 5O,R, 6I, 7C,D). R codes used for data import and analysis is provided.

Article and author information

Author details

  1. Savani Anbalagan

    Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  2. Janna Blechman

    Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  3. Michael Gliksberg

    Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  4. Ludmila Gordon

    Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  5. Ron Rotkopf

    Bioinformatics and Biological Computing Unit, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  6. Tali Dadosh

    Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  7. Eyal Shimoni

    Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
    Competing interests
    The authors declare that no competing interests exist.

  8. Gil Levkowitz

    Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
    For correspondence
    gil.levkowitz@weizmann.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3896-1881

Funding

Israel Science Foundation (1511/16)

  • Savani Anbalagan
  • Janna Blechman
  • Michael Gliksberg
  • Ludmila Gordon
  • Gil Levkowitz

Israel Science Foundation (2137/16)

  • Savani Anbalagan
  • Janna Blechman
  • Michael Gliksberg
  • Ludmila Gordon
  • Gil Levkowitz

Minerva Foundation ((Minerva Stiftung))

  • Savani Anbalagan
  • Janna Blechman
  • Michael Gliksberg
  • Ludmila Gordon
  • Gil Levkowitz

United States-Israel Binational Science Foundation (2017325)

  • Michael Gliksberg
  • Gil Levkowitz

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

Reviewing Editor

  1. Reinhard Jahn, Max Planck Institute for Biophysical Chemistry, Germany

Ethics

Animal experimentation: Experiments involving zebrafish were approved by the Weizmann Institute'sInstitutional Animal Care and Use Committee (protocol #27220516)

Version history

  1. Received: January 30, 2019
  2. Accepted: June 8, 2019
  3. Accepted Manuscript published: June 10, 2019 (version 1)
  4. Version of Record published: June 24, 2019 (version 2)
  5. Version of Record updated: October 5, 2020 (version 3)

Copyright

© 2019, Anbalagan 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. Savani Anbalagan
  2. Janna Blechman
  3. Michael Gliksberg
  4. Ludmila Gordon
  5. Ron Rotkopf
  6. Tali Dadosh
  7. Eyal Shimoni
  8. Gil Levkowitz
(2019)
Robo2 regulates synaptic oxytocin content by affecting actin dynamics
eLife 8:e45650.
https://doi.org/10.7554/eLife.45650

Share this article

https://doi.org/10.7554/eLife.45650

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