1. Biochemistry and Chemical Biology
  2. Neuroscience
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Precise optical control of gene expression in C. elegans using improved genetic code expansion and Cre recombinase

  1. Lloyd Davis
  2. Inja Radman
  3. Angeliki Goutou
  4. Ailish Tynan
  5. Kieran Baxter
  6. Zhiyan Xi
  7. Jack M O'Shea
  8. Jason W Chin  Is a corresponding author
  9. Sebastian Greiss  Is a corresponding author
  1. University of Edinburgh, United Kingdom
  2. MRC Laboratory of Molecular Biology, United Kingdom
  3. Medical Research Council Laboratory of Molecular Biology, United Kingdom
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Cite this article as: eLife 2021;10:e67075 doi: 10.7554/eLife.67075

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.

Article and author information

Author details

  1. Lloyd Davis

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Inja Radman

    Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Angeliki Goutou

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Ailish Tynan

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Kieran Baxter

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Zhiyan Xi

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Jack M O'Shea

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9694-7340
  8. Jason W Chin

    Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    chin@mrc-lmb.cam.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  9. Sebastian Greiss

    Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
    For correspondence
    s.greiss@ed.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9130-0831

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.

Reviewing Editor

  1. Oliver Hobert, Howard Hughes Medical Institute, Columbia University, United States

Publication history

  1. Preprint posted: May 3, 2020 (view preprint)
  2. Received: January 30, 2021
  3. Accepted: August 4, 2021
  4. Accepted Manuscript published: August 5, 2021 (version 1)
  5. Version of Record published: September 17, 2021 (version 2)

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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