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DOE OSTI · 3676311

A modular chemigenetic calcium indicator for multiplexed in vivo functional imaging

Farrants, Helen (ORCID:000000032494886X)·Shuai, Yichun (ORCID:000000019243425X)·Lemon, William (ORCID:000000034541738X)·Monroy Hernandez, Christian (ORCID:000000023796989X)·Zhang, Deng (ORCID:0000000215239503)·Yang, Shang (ORCID:0000000166717571)·Patel, Ronak (ORCID:0000000269456466)·Qiao, Guanda (ORCID:0000000224836393)·Frei, Michelle (ORCID:0000000247994554)·Plutkis, Sarah (ORCID:0009000318220466)·Grimm, Jonathan (ORCID:0000000303314200)·Hanson, Timothy (ORCID:0000000269110094)·Tomaska, Filip (ORCID:0000000225469599)·Turner, Glenn (ORCID:0000000253412784)·Stringer, Carsen (ORCID:0000000292294100)·Keller, Philipp (ORCID:0000000328964920)·Beyene, Abraham (ORCID:0000000338962144)·Chen, Yao (ORCID:0000000315096634)·Liang, Yajie (ORCID:0000000247984882)·Lavis, Luke (ORCID:0000000207896343)·Schreiter, Eric (ORCID:0000000228647469)
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Abstract

Abstract Genetically encoded fluorescent calcium indicators allow cellular-resolution recording of physiology. However, bright, genetically targetable indicators that can be multiplexed with existing tools in vivo are needed for simultaneous imaging of multiple signals. Here we describe WHaloCaMP, a modular chemigenetic calcium indicator built from bright dye-ligands and protein sensor domains. Fluorescence change in WHaloCaMP results from reversible quenching of the bound dye via a strategically placed tryptophan. WHaloCaMP is compatible with rhodamine dye-ligands that fluoresce from green to near-infrared, including several that efficiently label the brain in animals. When bound to a near-infrared dye-ligand, WHaloCaMP shows a 7× increase in fluorescence intensity and a 2.1-ns increase in fluorescence lifetime upon calcium binding. We use WHaloCaMP1a to image Ca 2+ responses in vivo in flies and mice, to perform three-color multiplexed functional imaging of hundreds of neurons and astrocytes in zebrafish larvae and to quantify Ca 2+ concentration using fluorescence lifetime imaging microscopy (FLIM).

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Farrants, Helen (ORCID:000000032494886X), Shuai, Yichun (ORCID:000000019243425X), Lemon, William (ORCID:000000034541738X), Monroy Hernandez, Christian (ORCID:000000023796989X), Zhang, Deng (ORCID:0000000215239503), Yang, Shang (ORCID:0000000166717571), Patel, Ronak (ORCID:0000000269456466), Qiao, Guanda (ORCID:0000000224836393), Frei, Michelle (ORCID:0000000247994554), Plutkis, Sarah (ORCID:0009000318220466), Grimm, Jonathan (ORCID:0000000303314200), Hanson, Timothy (ORCID:0000000269110094), Tomaska, Filip (ORCID:0000000225469599), Turner, Glenn (ORCID:0000000253412784), Stringer, Carsen (ORCID:0000000292294100), Keller, Philipp (ORCID:0000000328964920), Beyene, Abraham (ORCID:0000000338962144), Chen, Yao (ORCID:0000000315096634), Liang, Yajie (ORCID:0000000247984882), Lavis, Luke (ORCID:0000000207896343), Schreiter, Eric (ORCID:0000000228647469). 2024-09-20. A modular chemigenetic calcium indicator for multiplexed in vivo functional imaging. https://doi.org/10.1038/s41592-024-02411-6

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