Visualizing synaptic plasticity in vivo by large-scale imaging of endogenous AMPA receptors
- Johns Hopkins University School of Medicine, United States
- Johns Hopkins University, United States
Abstract
Elucidating how synaptic molecules such as AMPA receptors mediate neuronal communication and tracking their dynamic expression during behavior is crucial to understand cognition and disease, but current technological barriers preclude large-scale exploration of molecular dynamics in vivo. We have developed a suite of innovative methodologies that break through these barriers: a new knockin mouse line with fluorescently tagged endogenous AMPA receptors, two-photon imaging of hundreds of thousands of labeled synapses in behaving mice, and computer-vision-based automatic synapse detection. Using these tools, we can longitudinally track how the strength of populations of synapses changes during behavior. We used this approach to generate an unprecedentedly detailed spatiotemporal map of synapses undergoing changes in strength following sensory experience. More generally, these tools can be used as an optical probe capable of measuring functional synapse strength across entire brain areas during any behavioral paradigm, describing complex system-wide changes with molecular precision.
Data availability
We have provided Source data for our Figures and deposited the remaining data to Dryad with doi:10.5061/dryad.ttdz08m0b. All code used to analyze and process data is freely available on GitHub, with links specified in the manuscript.
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Raw data for Graves et. al 2021 eLifeDryad Digital Repository, doi:10.5061/dryad.ttdz08m0b.
Article and author information
Author details
Joshua T Vogelstein
Funding
National Institutes of Health (R21 AG063193)
- Austin R Graves
- Richard L Huganir
Kavli Foundation
- Austin R Graves
- Alina C Spiegel
- Daniel J Tward
National Institutes of Health (R01 MH123212)
- Austin R Graves
- Alexei M Bygrave
- Michael I Miller
- Richard L Huganir
Schmidt Science Nascent Innovation Grant (1)
- Austin R Graves
- Joshua T Vogelstein
- Richard L Huganir
National Institutes of Health (K99 MH124920)
- Alexei M Bygrave
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: These studies were conducted in accordance with US Public Health Service on Human Care and Use of Laboratory Animals (PHS Policy) and all procedures involving animals were approved by the Johns Hopkins Animal Care and Use Committee (ACUC) protocols (MO19M274, MO20M372, MO20M92, MO20M336). All surgeries were performed under isoflourane anesthesia. Every effort was made to reduce or eliminate pain and suffering during all surgical procedures, in vivo imaging sessions, and behavioral experiments.
Copyright
© 2021, Graves 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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Visualizing synaptic plasticity in vivo by large-scale imaging of endogenous AMPA receptors
eLife 10:e66809.
https://doi.org/10.7554/eLife.66809
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