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Real-Time Proxy-Control of Re-Parameterized Peripheral Signals using a Close-Loop Interface
Published on: May 8, 2021
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A mixed incoherent feed-forward loop allows conditional regulation of response dynamics.
1Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
Plos One
|March 14, 2014
Summary
This study shows that a specific regulatory network in E. coli allows faster responses to superoxide stress under low iron conditions. This feed forward loop conditionally modulates response times for superoxide dismutase expression.
Area of Science:
- Microbiology
- Molecular Biology
- Systems Biology
Background:
- Escherichia coli's SodA (MnSOD) expression is controlled by superoxide levels via SoxRS and iron levels via Fur and RyhB RNA.
- A mixed incoherent feed forward loop (FFL) integrates these regulatory signals.
Purpose of the Study:
- To theoretically analyze the function of the Fur-RyhB FFL in regulating cytoplasmic superoxide dismutases (SodA and SodB) in E. coli.
- To understand how this FFL impacts the cellular response to superoxide stress under varying iron concentrations.
Main Methods:
- Theoretical analysis of gene regulatory network dynamics.
- Mathematical modeling of transcriptional regulation.
Main Results:
- The feed forward loop enables a faster cellular response to superoxide stress when intracellular iron levels are low.
- The FFL's regulatory effect is conditional, modulating response times based on iron availability.
Conclusions:
- The identified FFL provides a mechanism for conditional modulation of gene expression response times.
- This regulatory strategy enhances bacterial adaptation to oxidative stress in environments with fluctuating iron levels.
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