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bioRxiv · 10.1101/675736

A live-cell screen for altered Erk dynamics reveals principles of proliferative control

Goglia, A. G.·Wilson, M. Z.·Silbert, J.·Jena, S.·Devenport, D.·Toettcher, J. E.
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Abstract

Complex, time-varying responses have been observed widely in cell signaling, but how specific dynamics are generated or regulated is largely unknown. One major obstacle has been that high-throughput screens for identifying pathway components are typically incompatible with the live-cell assays used to monitor dynamics. Here, we address this challenge by performing a drug screen for altered Erk signaling dynamics in primary mouse keratinocytes. We screened a library of 429 kinase inhibitors, monitoring Erk activity over 5 h in more than 80,000 single live cells. The screen revealed both known and uncharacterized modulators of Erk dynamics, including inhibitors of non-EGFR receptor tyrosine kinases (RTKs) that increased Erk pulse frequency and overall activity. Using drug treatment and direct optogenetic control, we demonstrate that drug-induced changes to Erk dynamics alter the conditions under which cells proliferate. Our work opens the door to high-throughput screens using live-cell biosensors and reveals that cell proliferation integrates information from Erk dynamics as well as additional permissive cues.

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Goglia, A. G., Wilson, M. Z., Silbert, J., Jena, S., Devenport, D., Toettcher, J. E.. 2019-06-19. A live-cell screen for altered Erk dynamics reveals principles of proliferative control. https://doi.org/10.1101/675736

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