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bioRxiv · 10.1101/2022.02.22.481562

A light-gated transcriptional recorder for detecting cell-cell contacts

Cho, K. F.·Gillespie, S. M.·Kalogriopoulos, N. A.·Quezada, M. A.·Jacko, M.·Monje, M.·Ting, A. Y.
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Abstract

Technologies for detecting cell-cell contacts are powerful tools for studying a wide range of biological processes, from neuronal signaling to cancer-immune interactions within the tumor microenvironment. Here we report TRACC, a GPCR-based transcriptional recorder of cellular contacts, which converts contact events into stable transgene expression. TRACC is derived from our previous protein-protein interaction recorders, SPARK (Kim et al., 2017) and SPARK2 (Kim et al., 2019). TRACC incorporates light gating via the LOV domain, which provides user-defined temporal control of tool activation and reduces background. We show that TRACC detects cell-cell contacts with high specificity and sensitivity in mammalian cell culture and that it can be used to interrogate interactions between neurons and glioma, a form of brain cancer.

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Cho, K. F., Gillespie, S. M., Kalogriopoulos, N. A., Quezada, M. A., Jacko, M., Monje, M., Ting, A. Y.. 2022-02-23. A light-gated transcriptional recorder for detecting cell-cell contacts. https://doi.org/10.1101/2022.02.22.481562

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