Self-organization of modular network architecture by activity-dependent neuronal migration and outgrowth

  1. Samora Okujeni  Is a corresponding author
  2. Ulrich Egert
  1. University of Freiburg, Germany

Abstract

The spatial distribution of neurons and activity-dependent neurite outgrowth shape long-range interaction, recurrent local connectivity and the modularity in neuronal networks. We investigated how this mesoscale architecture develops by interaction of neurite outgrowth, cell migration and activity in cultured networks of rat cortical neurons and show that simple rules can explain variations of network modularity. In contrast to theoretical studies on activity-dependent outgrowth but consistent with predictions for modular networks, spontaneous activity and the rate of synchronized bursts increased with clustering, whereas peak firing rates in bursts increased in highly interconnected homogeneous networks. As Ca2+ influx increased exponentially with increasing network recruitment during bursts, its modulation was highly correlated to peak firing rates. During network maturation, long-term estimates of Ca2+ influx showed convergence, even for highly different mesoscale architectures, neurite extent, connectivity, modularity and average activity levels, indicating homeostatic regulation towards a common set-point of Ca2+ influx.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Matlab code and source data files have been provided for Figures 3-6.

Article and author information

Author details

  1. Samora Okujeni

    Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
    For correspondence
    samora.okujeni@biologie.uni-freiburg.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7924-3651
  2. Ulrich Egert

    Department of Microsystems Engineering, Faculty of Engineering, University of Freiburg, Freiburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4583-0425

Funding

Deutsche Forschungsgemeinschaft (EXC 1086)

  • Ulrich Egert

Bundesministerium für Bildung und Forschung (FKZ 01GQ0420)

  • Ulrich Egert

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

Reviewing Editor

  1. Timothy O'Leary, University of Cambridge, United Kingdom

Ethics

Animal experimentation: Animal handling and tissue preparation were done in accordance with the guidelines for animal research at the University of Freiburg and approved by the Regierungspräsidium Freiburg (permits X-12/08D, X-16/07A, X-15/01H, X-18/04K).

Version history

  1. Received: April 26, 2019
  2. Accepted: September 16, 2019
  3. Accepted Manuscript published: September 17, 2019 (version 1)
  4. Version of Record published: October 8, 2019 (version 2)
  5. Version of Record updated: October 11, 2019 (version 3)

Copyright

© 2019, Okujeni & Egert

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. Samora Okujeni
  2. Ulrich Egert
(2019)
Self-organization of modular network architecture by activity-dependent neuronal migration and outgrowth
eLife 8:e47996.
https://doi.org/10.7554/eLife.47996

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https://doi.org/10.7554/eLife.47996

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