Light-controlled engagement of microglia to focally remodel synapses in the adult brain

  1. Carla Cangalaya
  2. Stoyan Stoyanov
  3. Klaus-Dieter Fischer
  4. Alexander Dityatev  Is a corresponding author
  1. Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE), Germany
  2. Institute of Biochemistry and Cell Biology, Germany

Abstract

Microglia continuously monitor synapses, but active synaptic remodelling by microglia in mature healthy brains is rarely directly observed. We performed targeted photoablation of single synapses in mature transgenic mice expressing fluorescent labels in neurons and microglia. The photodamage focally increased the duration of microglia-neuron contacts, and dramatically exacerbated both the turnover of dendritic spines and presynaptic boutons as well as the generation of new filopodia originating from spine heads or boutons. The results of microglia depletion confirmed that elevated spine turnover and the generation of presynaptic filopodia are microglia-dependent processes.

Data availability

All measurements, statistical analyses and the R code generated and used in this study are included in the manuscript.

Article and author information

Author details

  1. Carla Cangalaya

    Molecular Neuroplasticity Group, Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE), Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Stoyan Stoyanov

    Molecular Neuroplasticity Group, Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE), Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Klaus-Dieter Fischer

    OVGU-University of Magdeburg, Institute of Biochemistry and Cell Biology, Magdeburg, Germany
    Competing interests
    The authors declare that no competing interests exist.
  4. Alexander Dityatev

    Molecular Neuroplasticity Group, Deutsches Zentrum für Neurodegenerative Erkrankungen e.V. (DZNE), Magdeburg, Germany
    For correspondence
    alexander.dityatev@dzne.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3525-8445

Funding

The federal state Saxony-Anhalt and the European Structural and Investment Funds (ZS/2016/08/80645)

  • Klaus-Dieter Fischer
  • Alexander Dityatev

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

Ethics

Animal experimentation: All animals were treated in strict accordance with ethical animal research standards defined by the Directive 2010/63/EU, German law and approved by the Ethical Committee on Animal Health and Care of Saxony-Anhalt state, Germany (license number: 42502-2-1346).

Reviewing Editor

  1. Beth Stevens, Boston Children's Hospital, United States

Publication history

  1. Received: April 30, 2020
  2. Accepted: August 18, 2020
  3. Accepted Manuscript published: August 18, 2020 (version 1)
  4. Version of Record published: September 3, 2020 (version 2)

Copyright

© 2020, Cangalaya 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. Carla Cangalaya
  2. Stoyan Stoyanov
  3. Klaus-Dieter Fischer
  4. Alexander Dityatev
(2020)
Light-controlled engagement of microglia to focally remodel synapses in the adult brain
eLife 9:e58435.
https://doi.org/10.7554/eLife.58435

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