Advanced deep-tissue imaging and manipulation enabled by biliverdin reductase knockout.

Kasatkina, L.; Ma, C.; Sheng, H.; Lowerison, M.; Menozzi, L.; Baloban, M.; Tang, Y.; Xu, Y.; Humayun, L.; Vu, T.; Song, P.; Yao, J.; Verkhusha, V.

doi:10.1101/2024.10.18.619161

bioRxiv · 10.1101/2024.10.18.619161

Advanced deep-tissue imaging and manipulation enabled by biliverdin reductase knockout.

Kasatkina, L.·Ma, C.·Sheng, H.·Lowerison, M.·Menozzi, L.·Baloban, M.·Tang, Y.·Xu, Y.·Humayun, L.·Vu, T.·Song, P.·Yao, J.·Verkhusha, V.

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Abstract

We developed near-infrared (NIR) photoacoustic and fluorescence probes, as well as optogenetic tools from bacteriophytochromes, and enhanced their performance using biliverdin reductase-A knock-out model (Blvra-/-). Blvra-/- elevates endogenous heme-derived biliverdin chromophore for bacteriophytochrome-derived NIR constructs. Consequently, light-controlled transcription with IsPadC-based optogenetic tool improved up to 25-fold compared to wild-type cells, with 100-fold activation in Blvra-/- neurons. In vivo, light-induced insulin production in Blvra-/- reduced blood glucose in diabetes by [~]60%, indicating high potential for optogenetic therapy. Using 3D photoacoustic, ultrasound, and two-photon fluorescence imaging, we overcame depth limitations of recording NIR probes. We achieved simultaneous photoacoustic imaging of DrBphP in neurons and super-resolution ultrasound localization microscopy of blood vessels [~]7 mm deep in the brain, with intact scalp and skull. Two-photon microscopy provided cell-level resolution of miRFP720-expressing neurons [~]2.2 mm deep. Blvra-/- significantly enhances efficacy of biliverdin-dependent NIR systems, making it promising platform for interrogation and manipulation of biological processes.

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Kasatkina, L., Ma, C., Sheng, H., Lowerison, M., Menozzi, L., Baloban, M., Tang, Y., Xu, Y., Humayun, L., Vu, T., Song, P., Yao, J., Verkhusha, V.. 2024-10-18. Advanced deep-tissue imaging and manipulation enabled by biliverdin reductase knockout.. https://doi.org/10.1101/2024.10.18.619161

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