Decoding stimulus-specific regulation of promoter activity of p53 target genes
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View abstract on PubMed
Summary
This summary is machine-generated.The tumor suppressor p53 regulates gene expression in response to DNA damage through dynamic, stochastic bursts. Its transcriptional activity depends on promoter switching rates, not just p53 levels, revealing complex control of cellular responses.
Area Of Science
- Molecular Biology
- Genetics
- Cell Biology
Background
- The tumor suppressor p53 is critical for genome integrity, responding to cellular stress by regulating genes involved in apoptosis, cell cycle arrest, and DNA repair.
- Gene transcription is inherently stochastic, characterized by bursts of activity and promoter switching, leading to cell-to-cell variability in gene expression.
- Understanding how p53 dynamics translate into specific gene regulation patterns under various DNA damage conditions is crucial for comprehending cellular responses.
Purpose Of The Study
- To investigate how stimulus-dependent p53 dynamics are converted into specific gene regulation patterns following diverse DNA damage.
- To quantify target gene promoter activity at single-cell and single-molecule levels using advanced imaging techniques.
- To develop a computational framework for analyzing stochastic gene expression data and inferring regulatory parameters.
Main Methods
- Induction of various DNA damage types (ionizing radiation, UV radiation, chemotherapeutics).
- Single molecule fluorescence in situ hybridization (smFISH) for quantifying promoter activity.
- Bayesian inference framework for analyzing stochastic gene expression parameters.
Main Results
- Stimulus-specific p53-mediated gene expression patterns are differentially regulated based on the target gene and DNA damage type/extent.
- Stochastic gene expression is primarily controlled by promoter activation and deactivation rates.
- Transcriptional activity was often uncoupled from total p53 levels or DNA-bound fractions, indicating multi-dimensional regulation.
Conclusions
- p53's role in transcriptional regulation is complex and multi-dimensional, extending beyond simple concentration-dependent effects.
- Stimulus-specific promoter switching dynamics are key to translating p53 activation into distinct cellular responses to DNA damage.
- This study provides novel insights into the stochastic nature of p53-mediated gene regulation in response to DNA damage.
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