Computer assisted detection of axonal bouton structural plasticity in in vivo time-lapse images

  1. Rohan Gala
  2. Daniel Lebrecht
  3. Daniela A Sahlender
  4. Anne Jorstad
  5. Graham Knott
  6. Anthony Holtmaat
  7. Armen Stepanyants  Is a corresponding author
  1. Northeastern University, United States
  2. University of Geneva, Switzerland
  3. École Polytechnique Fédérale de Lausanne, Switzerland

Abstract

The ability to measure minute structural changes in neural circuits is essential for long-term in vivo imaging studies. Here, we propose a methodology for detection and measurement of structural changes in axonal boutons imaged with time-lapse two-photon laser scanning microscopy (2PLSM). Correlative 2PLSM and 3D electron microscopy (EM) analysis, performed in mouse barrel cortex, showed that the proposed method has low fractions of false positive/negative bouton detections (2/0 out of 18), and that 2PLSM-based bouton weights are correlated with their volumes measured in EM (r=0.93). Next, the method was applied to a set of axons imaged in quick succession to characterize measurement uncertainty. The results were used to construct a statistical model in which bouton addition, elimination, and size changes are described probabilistically, rather than being treated as deterministic events. Finally, we demonstrate that the model can be used to quantify significant structural changes in boutons in long-term imaging experiments.

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Author details

  1. Rohan Gala

    Department of Physics, Northeastern University, Boston, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Daniel Lebrecht

    Department of Basic Neurosciences, Faculty of Medicine, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Daniela A Sahlender

    Biological Electron Microscopy Facility, Centre of Electron Microscopy, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Anne Jorstad

    Biological Electron Microscopy Facility, Centre of Electron Microscopy, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6438-1979
  5. Graham Knott

    Biological Electron Microscopy Facility, Centre of Electron Microscopy, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2956-9052
  6. Anthony Holtmaat

    Department of Basic Neurosciences, Faculty of Medicine, University of Geneva, Geneva, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  7. Armen Stepanyants

    Department of Physics, Northeastern University, Boston, United States
    For correspondence
    a.stepanyants@neu.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9387-2320

Funding

National Institutes of Health (R01 NS091421)

  • Armen Stepanyants

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (331003A_153448)

  • Anthony Holtmaat

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (CRSII3-154453)

  • Graham Knott
  • Anthony Holtmaat

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (51NF40_158776)

  • Anthony Holtmaat

International Foundation for Research in Paraplegia (Chair Alain Rossier)

  • Anthony Holtmaat

Air Force Office of Scientific Research (FA9550-15-1-0398)

  • Armen Stepanyants

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 experiments were performed according to the guidelines of the Swiss Federal Act on Animal Protection and Swiss Animal Protection Ordinance. The ethics committee of the University of Geneva and the Cantonal Veterinary Office of Geneva, Switzerland (approval code GE/61/17) approved all experiments.

Reviewing Editor

  1. Eve Marder, Brandeis University, United States

Publication history

  1. Received: June 6, 2017
  2. Accepted: October 22, 2017
  3. Accepted Manuscript published: October 23, 2017 (version 1)
  4. Version of Record published: November 7, 2017 (version 2)

Copyright

© 2017, Gala 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. Rohan Gala
  2. Daniel Lebrecht
  3. Daniela A Sahlender
  4. Anne Jorstad
  5. Graham Knott
  6. Anthony Holtmaat
  7. Armen Stepanyants
(2017)
Computer assisted detection of axonal bouton structural plasticity in in vivo time-lapse images
eLife 6:e29315.
https://doi.org/10.7554/eLife.29315

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