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Bistable responses in bacterial genetic networks: designs and dynamical consequences
Abhinav Tiwari1, J Christian J Ray, Jatin Narula
1Department of Bioengineering, Rice University, Houston, TX 77005, USA.
Mathematical Biosciences
|March 10, 2011
Summary
Cellular responses to stimuli can be bistable, meaning they have two stable states. This review explores how evolutionary principles shape these biochemical networks in bacteria.
Area of Science:
- Biochemistry
- Systems Biology
- Molecular Biology
Background:
- Living cells respond to stimuli via biochemical and genetic networks.
- Networks can exhibit graded (continuous) or bistable (two stable states) responses.
- Bistability allows systems to maintain distinct states over a range of signals.
Purpose of the Study:
- To review conceptual examples of network designs leading to bistability.
- To examine bistability in bacterial master-regulatory genetic circuits.
- To understand evolutionary design principles of bistable networks.
Main Methods:
- Conceptual review of network designs.
- Examination of bacterial genetic circuits (two-component systems, sigma-factor networks, multistep phosphorelays).
- Analysis of mechanisms and dynamic consequences of bistability.
Main Results:
- Several conceptual network designs can generate bistable responses.
- Bistability is observed in key bacterial regulatory circuits.
- Specific mechanisms driving bistability in these circuits are discussed.
Conclusions:
- Bistable responses are a significant feature of cellular regulation.
- Evolutionary principles guide the design of these complex networks.
- Understanding bistability enhances knowledge of cellular information processing.
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