A calibrated optogenetic toolbox of stable zebrafish opsin lines
Optogenetic actuators with diverse spectral tuning, ion selectivity and kinetics are constantly being engineered providing powerful tools for controlling neural activity with subcellular resolution and millisecond precision. Achieving reliable and interpretable in vivo optogenetic manipulations requires reproducible actuator expression and calibration of photocurrents in target neurons. Here, we developed nine transgenic zebrafish lines for stable opsin expression and calibrated their efficacy in vivo. We first used high-throughput behavioural assays to compare opsin ability to elicit or silence neural activity. Next, we performed in vivo whole-cell electrophysiological recordings to quantify the amplitude and kinetics of photocurrents and test opsin ability to precisely control spiking. We observed substantial variation in efficacy, associated with differences in both opsin expression level and photocurrent characteristics, and identified conditions for optimal use of the most efficient opsins. Overall, our calibrated optogenetic toolkit will facilitate the design of controlled optogenetic circuit manipulations.
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all Figures.
Article and author information
Horizon 2020 Framework Programme (Marie Curie Incoming International Fellowship,H2020-MSCA-IF-2016 Project #752199)
- Adna Dumitrescu
Human Frontier Science Program (RGP063-2018)
- Claire Wyart
New York Stem Cell Foundation (NYSCF-R-NI39)
- Claire Wyart
Wellcome (Sir Henry Wellcome Postdoctoral Fellowship,204708/Z/16/Z)
- Paride Antinucci
Wellcome (Sir Henry Dale Fellowship,101195/Z/13/Z)
- Isaac H Bianco
Royal Society (Sir Henry Dale Fellowship,101195/Z/13/Z)
- Isaac H Bianco
University College London (Excellence Fellowship)
- Isaac H Bianco
Human Frontier Science Program (Long-term Fellowship,LT393/2010)
- Fumi Kubo
Deutsche Forschungsgemeinschaft (Next-Generation Optogenetics,SPP1926)
- Herwig Baier
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All larvae used for behavioural assays were fed Paramecia from 4 dpf onward. Animal handling and experimental procedures were approved by the UCL Animal Welfare Ethical Review Body and the UK Home Office under the Animal (Scientific Procedures) Act 1986.In vivo electrophysiological recordings were performed in 5-6 dpf zebrafish larvae from AB and Tüpfel long fin (TL) strains in accordance with the European Communities Council Directive (2010/63/EU) and French law (87/848) and approved by the Institut du Cerveau et de la Moelle épinière, the French ministry of Research and the Darwin Ethics Committee (APAFIS protocol #16469-2018071217081175v5).
- Harold Burgess
- Received: January 7, 2020
- Accepted: March 27, 2020
- Accepted Manuscript published: March 27, 2020 (version 1)
- Version of Record published: April 20, 2020 (version 2)
© 2020, Antinucci 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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