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bioRxiv · 10.1101/2021.12.22.473920

A dual-purpose real-time indicator and transcriptional integrator for calcium detection in living cells

Erdenee, E.·Ting, A. Y.
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Abstract

Calcium is a ubiquitous second messenger in eukaryotes, correlated with neuronal activity and T-cell activation among other processes. Real-time calcium indicators such as GCaMP have recently been complemented by newer calcium integrators that convert transient calcium activity into stable gene expression. Here we introduce LuCID, a dual-purpose real-time calcium indicator and transcriptional calcium integrator that combines the benefits of both calcium detection technologies. We show that the calcium-dependent split luciferase component of LuCID provides real-time bioluminescence readout of calcium dynamics in cells, while the GI/FKF1 split GAL4 component of LuCID converts calcium-generated bioluminescence into stable gene expression. We also show that LuCIDs modular design enables it to also read out other cellular events such as protein-protein interactions. LuCID adds to the arsenal of tools for studying cells and cell populations that utilize calcium for signaling.

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Erdenee, E., Ting, A. Y.. 2021-12-22. A dual-purpose real-time indicator and transcriptional integrator for calcium detection in living cells. https://doi.org/10.1101/2021.12.22.473920

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