Computer assisted detection of axonal bouton structural plasticity in in vivo time-lapse images
- Northeastern University, United States
- University of Geneva, Switzerland
- 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.
Data availability
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Data from: Computer assisted detection of axonal bouton structural plasticity in in vivo time-lapse imagesAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
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.
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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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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