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bioRxiv · 10.1101/2025.07.22.665990

Chemogenetic and optogenetic strategies for spatiotemporal control of split-enzyme-based calcium recording

Zhang, Y.·Campmier, B. K.·Sharma, A.·Eckartt, K. N.·Laughlin, S. T.
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Abstract

Methods for monitoring physiological changes in cellular Ca2+ levels have been in high demand for their utility in monitoring neuronal signaling. Recently, we introduced SCANR (Split-Tobacco Etch Virus (TEV) protease Calcium-regulated Neuron Recorder), which reports on Ca2+ changes in cells through the binding of calmodulin and M13 to reconstitute an active TEV protease. First-generation SCANR marked all of the Ca2+ spikes that occur throughout the lifetime of the cell, but it did not have a mechanism for controlling the time window in which recording of physiological changes in Ca2+ occurred. Here, we explore both chemical and light-based strategies for controlling the time and place in which Ca2+ recording occurs. We describe the adaptation of six popular chemo- and opto-genetics methods for controlling protein activity and subcellular localization to the SCANR system. We report two successful strategies, one that leverages the LOV-J optogenetics system for sterically controlling protein interactions and another that employs chemogenetic manipulation of subcellular protein distribution using the FKBP/FRB rapamycin binding pair.

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Zhang, Y., Campmier, B. K., Sharma, A., Eckartt, K. N., Laughlin, S. T.. 2025-07-26. Chemogenetic and optogenetic strategies for spatiotemporal control of split-enzyme-based calcium recording. https://doi.org/10.1101/2025.07.22.665990

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