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bioRxiv · 10.1101/761775

Regulation of mRNA translation by a photoriboswitch

Rotstan, K. A.·Abdesayed, M. M.·Passalacqua, L. F. M.·Chizzolini, F.·Sudarshan, K.·Chamberlin, A. R.·Misek, J.·Luptak, A.
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Abstract

Optogenetic tools have revolutionized the study of receptor-mediated biological processes, but such tools are lacking for the study of RNA-controlled systems. To fill this gap, we used in vitro selection to isolate a novel RNA 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 amino-cSS, giving the system robust selectivity for the trans isomer. 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 and photoisomerization of the ligand with a sub-millisecond pulse of light induced the protein expression. Similarly, bacterial culture containing the cis isoform (amino-cSS) supported protein expression, which was inhibited upon photoisomerization to amino-tSS. Reversible regulation of gene expression using a genetically encoded light-responsive RNA will broaden the analysis of complex RNA processes in living cells.

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Rotstan, K. A., Abdesayed, M. M., Passalacqua, L. F. M., Chizzolini, F., Sudarshan, K., Chamberlin, A. R., Misek, J., Luptak, A.. 2019-09-08. Regulation of mRNA translation by a photoriboswitch. https://doi.org/10.1101/761775

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