A FRET-based excitatory luminopsin with improved efficacy of bioluminescence-driven activation

Bjorefeldt, A.; Murphy, J.; Crespo, E. L.; Prakash, M.; Friedman, N.; Brown, T. M.; Lipscombe, D.; Moore, C. I.; Hochgeschwender, U.; Shaner, N. C.

doi:10.1101/2023.06.26.545546

bioRxiv · 10.1101/2023.06.26.545546

A FRET-based excitatory luminopsin with improved efficacy of bioluminescence-driven activation

Bjorefeldt, A.·Murphy, J.·Crespo, E. L.·Prakash, M.·Friedman, N.·Brown, T. M.·Lipscombe, D.·Moore, C. I.·Hochgeschwender, U.·Shaner, N. C.

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Abstract

SignificanceBioluminescent optogenetics (BL-OG) offers a unique and powerful approach to manipulate neural activity both opto- and chemogenetically using a single actuator molecule (a LuMinOpsin, LMO). AimTo further enhance the utility of BL-OG by improving the efficacy of chemogenetic (bioluminescence- driven) LMO activation. ApproachWe developed novel luciferases optimized for Forster resonance energy transfer (FRET) when fused to the fluorescent protein mNeonGreen, generating bright bioluminescent (BL) emitters spectrally tuned to Volvox Channelrhodopsin 1 (VChR1). ResultsA new LMO generated from this approach (LMO7) showed significantly stronger BL-driven opsin activation compared to previous and other new variants. We extensively benchmarked LMO7 against LMO3 (current standard), and found significantly stronger neuronal activity modulation ex vivo and in vivo, and efficient modulation of behavior. ConclusionsWe report a robust new option for achieving multiple modes of control in a single actuator, and a promising engineering strategy for continued improvement of BL-OG.

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Bjorefeldt, A., Murphy, J., Crespo, E. L., Prakash, M., Friedman, N., Brown, T. M., Lipscombe, D., Moore, C. I., Hochgeschwender, U., Shaner, N. C.. 2023-06-26. A FRET-based excitatory luminopsin with improved efficacy of bioluminescence-driven activation. https://doi.org/10.1101/2023.06.26.545546

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