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bioRxiv · 10.1101/2020.04.04.022145

A far-red fluorescent chemogenetic reporter for in vivo molecular imaging

Li, C.·Tebo, A. G.·Thauvin, M.·Plamont, M.-A.·Volovitch, M.·Morin, X.·Vriz, S.·Gautier, A.
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Abstract

Far-red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we describe the generation of frFAST (far-red Fluorescence Activating and absorption Shifting Tag), a 14-kDa monomeric protein that forms a bright far-red fluorescent assembly with (4-hydroxy-3-methoxy-phenyl)allylidene rhodanine (HPAR-3OM). As HPAR-3OM is essentially non-fluorescent in solution and in cells, frFAST can be imaged with high contrast in presence of free HPAR-3OM, which allowed the rapid and efficient imaging of frFAST fusions in live cells, zebrafish embryo/larvae and chicken embryo. Beyond enabling genetic encoding of far-red fluorescence, frFAST allowed the design of a far-red chemogenetic reporter of protein-protein interactions, demonstrating its great potential for the design of innovative far-red emitting biosensors.

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Li, C., Tebo, A. G., Thauvin, M., Plamont, M.-A., Volovitch, M., Morin, X., Vriz, S., Gautier, A.. 2020-04-05. A far-red fluorescent chemogenetic reporter for in vivo molecular imaging. https://doi.org/10.1101/2020.04.04.022145

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