Solaris: a panel of bright and sensitive hybrid voltage indicators for imaging membrane potential in cultured neurons
Year: 2024
Type: preprint
Abstract: Dynamic changes in the membrane potential underlie neuronal activities. Fluorescent voltage indicators allow optical recording of electrical signaling across a neuronal population with cellular precision and at millisecond-level temporal resolution. Here we report the design and characterization of a chemigenetic hybrid voltage indicator, Solaris, in which a circularly permuted HaloTag is inserted into the first extracellular loop of Acetabularia rhodopsin. Solaris is compatible with fluorogenic HaloTag ligands JF 525 , JF 549 , JF 552 , JF 585 , and JF 635 . The most sensitive conjugate, Solaris 585 , has more than 2-fold higher voltage sensitivity than the spectrally similar Voltron2 585 (ΔF/F 0 = -28.1 ± 1.3% versus -12.3 ± 0.7% per action potential in cultured neurons). Solaris 585 supports the measurement of optogenetically evoked spike activity or dual-color imaging in conjunction with green-emitting calcium or glutamate indicators. Solaris indicators are also applicable to fluorescence lifetime imaging, which probes the absolute membrane potential. This new hybrid voltage indicator is a valuable tool for imaging neuronal electrophysiological activities in cultured cells with substantially improved dynamic range compared to previous hybrid indicators.
Authors: Junqi Yang, Siyan Zhu, Luming Yang, Luxin Peng, Yi Han, Rebecca Frank Hayward, Pojeong Park, Dachao Hu, Adam E. Cohen, Peng Zou
Language: English
Subfield: Biophysics
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W4391518573