Gene expression in mammalian cells results from coordinated protein-driven processes guided by diverse mechanisms of regulation, including protein–protein interactions, protein localization, DNA modifications and chromatin rearrangement. Regulation of gene expression is particularly important in stress-response pathways. To address the need to monitor chromosomal gene expression generating a readily detectable signal output that recapitulates gene expression dynamics, we developed a gene signal amplifier platform that links transcriptional and post-translational regulation of a fluorescent output to the expression of a chromosomal target gene. We generated a multiplex reporter system for monitoring markers of the unfolded protein response, a complex signal transduction pathway that remodels gene expression in response to proteotoxic stress in the endoplasmic reticulum. By recapitulating the transcriptional and translational control mechanisms underlying the expression of a target gene with high sensitivity, this platform provides a technology for monitoring gene expression with superior sensitivity and dynamic resolution.
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The authors declare that data supporting the finding of this study are available within the article and its Supplementary Information. Additional data are available from the corresponding author upon reasonable request.
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This work was funded by the National Science Foundation (grant no. MCB-1615562, grant no. CBET-1805317 and grant no. CBET-1930149) and the Welch Foundation (grant no. C-1824), and was conducted in part using resources of the Shared Equipment Authority at Rice University. This project was supported by the Cytometry and Cell Sorting Core at Baylor College of Medicine, with funding from the CPRIT Core Facility Support Award (grant no. CPRIT-RP180672), and by the NIH (grant no. P30 CA125123 and grant no. S10 RR024574).
The authors declare no competing interests.
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Origel Marmolejo, C.A., Bachhav, B., Patibandla, S.D. et al. A gene signal amplifier platform for monitoring the unfolded protein response. Nat Chem Biol (2020). https://doi.org/10.1038/s41589-020-0497-x