The p53 tumor suppressor regulates distinct responses to cellular stresses. Although different stresses generate different p53 dynamics, the mechanisms by which cells decode p53 dynamics to differentially regulate target genes are not well understood. Here, we determined in individual cells how canonical p53 target gene promoters vary in responsiveness to features of p53 dynamics. Employing a chemical perturbation approach, we independently modulated p53 pulse amplitude, duration, or frequency, and we then monitored p53 levels and target promoter activation in individual cells. We identified distinct signal processing features—thresholding in response to amplitude modulation, a refractory period in response to duration modulation, and dynamic filtering in response to frequency modulation. We then showed that the signal processing features not only affect p53 target promoter activation, they also affect p53 regulation and downstream cellular functions. Our study shows how different promoters can differentially decode features of p53 dynamics to generate distinct responses, providing insight into how perturbing p53 dynamics can be used to generate distinct cell fates.
Bibliographical noteFunding Information:
We thank all members of the Batchelor laboratory and the Levens laboratory for thoughtful discussions. The pLV‐EF‐mCherry‐Geminin IRES‐Puro plasmid was kindly provided by S Cappell. We thank J Porter for assistance with data analysis. We thank M Aldred, J Wu, and C Corcoran for assistance with image analysis and plasmids. This work was supported by NIH grants 5R01GM124446 (to AS), 5R01GM126557 (to AS), and the Intramural Research Program of the Center for Cancer Research, National Cancer Institute, NIH project ZIA BC011382 (to EB).
© 2019 The Authors. Published under the terms of the CC BY 4.0 license
- gene regulation
- single cell
- transcription factor dynamics