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bioRxiv · 10.1101/2021.10.13.463730

Dual polarity voltage imaging reveals subthreshold dynamics and concurrent spiking patterns of multiple neuron-types

Kannan, M.·Vasan, G.·Haziza, S.·Huang, C.·Chrapkiewicz, R.·Luo, J.·Cardin, J. A.·Schnitzer, M. J.·Pieribone, V. A.
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Abstract

Genetically encoded fluorescent voltage indicators are ideally suited to reveal the millisecond-scale interactions among and between distinct, targeted cell populations. However, current indicator families lack the requisite sensitivity for in vivo multipopulation imaging. We describe high-performance green and red sensors, Ace-mNeon2 and VARNAM2, and their reverse response-polarity variants, pAce and pAceR. Our indicators enable 0.4-1 kHz voltage recordings from >50 neurons per field-of-view in awake mice and [~]30-min continuous imaging in flies. Using dual-polarity multiplexed imaging, we uncovered behavioral state-dependent interactions between distinct neocortical subclasses, as well as contributions to hippocampal field potentials from non-overlapping projection neuronal ensembles. By combining three mutually compatible indicators, we demonstrate concurrent triple-population voltage imaging. Our approach will empower investigations of the dynamic interplay between neuronal subclasses at single-spike resolution. One Sentence SummaryA new suite of voltage sensors enables simultaneous cellular-resolution activity imaging from multiple, targeted neuron-types in awake animals.

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Kannan, M., Vasan, G., Haziza, S., Huang, C., Chrapkiewicz, R., Luo, J., Cardin, J. A., Schnitzer, M. J., Pieribone, V. A.. 2021-10-15. Dual polarity voltage imaging reveals subthreshold dynamics and concurrent spiking patterns of multiple neuron-types. https://doi.org/10.1101/2021.10.13.463730

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