Regulation of mRNA translation by a photoriboswitch
- University of California, Irvine, United States
- Charles University, Czech Republic
Abstract
Optogenetic tools have revolutionized the study of receptor-mediated processes, but such tools are lacking for RNA-controlled systems. In particular, light-activated regulatory RNAs are needed for spatiotemporal control of gene expression. To fill this gap, we used in vitro selection to isolate a novel riboswitch that selectively binds the trans isoform of a stiff-stilbene (amino-tSS)–a rapidly and reversibly photoisomerizing small molecule. Structural probing revealed that the RNA binds amino-tSS about 100-times stronger than the cis photoisoform (amino-cSS). In vitro and in vivo functional analysis showed that the riboswitch, termed Werewolf-1 (Were-1), inhibits translation of a downstream open reading frame when bound to amino-tSS. Photoisomerization of the ligand with a sub-millisecond pulse of light induced the protein expression. In contrast, amino-cSS supported protein expression, which was inhibited upon photoisomerization to amino-tSS. Reversible photoregulation of gene expression using a genetically encoded RNA will likely facilitate high-resolution spatiotemporal analysis of complex RNA processes.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data file has been provided for all figures in an Excel file.
Article and author information
Author details
Luiz F M Passalacqua
Kasireddy Sudarshan
Funding
National Science Foundation (1804220)
- Andrej Luptak
National Institutes of Health (R01GM094929)
- Andrej Luptak
John Templeton Foundation
- Andrej Luptak
Grantová Agentura České Republiky (17-25897Y)
- Jiří Míšek
National Institutes of Health (Graduate Student Fellowship T32GM108561)
- Kelly A Rotstan
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Graduate Student Fellowship 99999.013571/2013-03)
- Luiz F M Passalacqua
University of California, Irvine (Miguel Velez Scholarship)
- Luiz F M Passalacqua
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Rotstan 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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Regulation of mRNA translation by a photoriboswitch
eLife 9:e51737.
https://doi.org/10.7554/eLife.51737
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