Precise optical control of gene expression in C. elegans using improved genetic code expansion and Cre recombinase
- University of Edinburgh, United Kingdom
- MRC Laboratory of Molecular Biology, United Kingdom
- Medical Research Council Laboratory of Molecular Biology, United Kingdom
Abstract
Synthetic strategies for optically controlling gene expression may enable the precise spatiotemporal control of genes in any combination of cells that cannot be targeted with specific promoters. We develop an improved genetic code expansion system in C. elegans and use it to create a photo-activatable Cre recombinase. We laser-activate Cre in single neurons within a bilaterally symmetric pair to selectively switch on expression of a loxP controlled optogenetic channel in the targeted neuron. We use the system to dissect, in freely moving animals, the individual contributions of the mechanosensory neurons PLML/PLMR to the C. elegans touch response circuit, revealing distinct and synergistic roles for these neurons. We thus demonstrate how genetic code expansion and optical targeting can be combined to break the symmetry of neuron pairs and dissect behavioural outputs of individual neurons that cannot be genetically targeted.
Data availability
All data are included in the manuscript and supporting files. Sequences used for generating transgenic constructs are listed in the supporting files.
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Author details
Funding
H2020 European Research Council (ERC-StG-679990)
- Sebastian Greiss
Medical Research Council (MC_U105181009)
- Jason W Chin
Medical Research Council (MC_UP_A024_1008)
- Jason W Chin
Wellcome-Trust University of Edinburgh Institutional Strategic Support Fund ISS2
- Sebastian Greiss
The Royal Society
- Sebastian Greiss
Muir Maxwell Epilepsy Centre
- Sebastian Greiss
Louis Jeantet Foundation
- Jason W Chin
Herchel Smith Foundation
- Inja Radman
University of Edinburgh, Edinburgh Global Award and Principal's Career Development PhD studentship
- Zhiyan Xi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Davis 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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Precise optical control of gene expression in C. elegans using improved genetic code expansion and Cre recombinase
eLife 10:e67075.
https://doi.org/10.7554/eLife.67075
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