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bioRxiv · 10.1101/769422

Green, orange, red, and far-red optogenetic tools derived from cyanobacteriochromes

Jang, J.·McDonald, S.·Uppalapati, M.·Woolley, A.
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Abstract

Existing optogenetic tools for controlling protein-protein interactions are available in a limited number of wavelengths thereby limiting opportunities for multiplexing. The cyanobacteriochrome (CBCR) family of photoreceptors responds to an extraordinary range of colors, but light-dependent binding partners for CBCR domains are not currently known. We used a phage-display based approach to develop small (~50-residue) monomeric binders selective for the green absorbing state (Pg), or for the red absorbing state (Pr) of the CBCR Am1_c0023g2 with a phycocyanobilin chromophore and also for the far-red absorbing state (Pfr) of Am1_c0023g2 with a biliverdin chromophore. These bind in a 1:1 mole ratio with KDs for the target state from 0.2 to 2 M and selectivities from 10 to 500-fold. We demonstrate green, orange, red, and far-red light-dependent control of protein-protein interactions in vitro and also in vivo where these multicolor optogenetic tools are used to control transcription in yeast.

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Jang, J., McDonald, S., Uppalapati, M., Woolley, A.. 2019-09-14. Green, orange, red, and far-red optogenetic tools derived from cyanobacteriochromes. https://doi.org/10.1101/769422

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