A single-chain and fast-responding light-inducible Cre recombinase as a novel optogenetic switch
Abstract
Optogenetics enables genome manipulations with high spatiotemporal resolution, opening exciting possibilities for fundamental and applied biological research. Here, we report the development of LiCre, a novel light-inducible Cre recombinase. LiCre is made of a single flavin-containing protein comprising the AsLOV2 photoreceptor domain of Avena sativa fused to a Cre variant carrying destabilizing mutations in its N-terminal and C-terminal domains. LiCre can be activated within minutes of illumination with blue light, without the need of additional chemicals. When compared to existing photoactivatable Cre recombinases based on two split units, LiCre displayed faster and stronger activation by light as well as a lower residual activity in the dark. LiCre was efficient both in yeast, where it allowed us to control the production of β-carotene with light, and in human cells. Given its simplicity and performances, LiCre is particularly suited for fundamental and biomedical research, as well as for controlling industrial bioprocesses.
Data availability
Raw flow-cytometry data have been deposited in Biostudies under accession code S-BSST580. Processed data used for figures are included in the supporting files.
Article and author information
Author details
Funding
H2020 European Research Council (StG-281359 (SiGHT))
- Gaël Yvert
Centre National de la Recherche Scientifique (MITI 80 Prime READGEN)
- Gaël Yvert
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Kevin H Gardner, CUNY Advanced Science Research Center, United States
Version history
- Received: July 20, 2020
- Accepted: February 22, 2021
- Accepted Manuscript published: February 23, 2021 (version 1)
- Version of Record published: March 26, 2021 (version 2)
Copyright
© 2021, Duplus-Bottin 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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