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Positive Autoregulation Shapes Response Timing and Intensity in Two-component Signal Transduction Systems

Overview
Journal J Mol Biol
Publisher Elsevier
Date 2010 Jul 6
PMID 20600106
Citations 16
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Abstract

Positive feedback loops are regulatory elements that can modulate expression output, kinetics and noise in genetic circuits. Transcriptional regulators participating in such loops are often expressed from two promoters, one constitutive and one autoregulated. Here, we investigate the interplay of promoter strengths and the intensity of the stimulus activating the transcriptional regulator in defining the output of a positively autoregulated genetic circuit. Using a mathematical model of two-component regulatory systems, which are present in all domains of life, we establish that positive feedback strongly affects the steady-state output levels at both low and high levels of stimulus if the constitutive promoter of the regulator is weak. By contrast, the effect of positive feedback is negligible when the constitutive promoter is sufficiently strong, unless the stimulus intensity is very high. Furthermore, we determine that positive feedback can affect both transient and steady state output levels even in the simplest genetic regulatory systems. We tested our modeling predictions by abolishing the positive feedback loop in the two-component regulatory system PhoP/PhoQ of Salmonella enterica, which resulted in diminished induction of PhoP-activated genes.

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References
1.
Purnick P, Weiss R . The second wave of synthetic biology: from modules to systems. Nat Rev Mol Cell Biol. 2009; 10(6):410-22. DOI: 10.1038/nrm2698. View

2.
Mitrophanov A, Jewett M, Hadley T, Groisman E . Evolution and dynamics of regulatory architectures controlling polymyxin B resistance in enteric bacteria. PLoS Genet. 2008; 4(10):e1000233. PMC: 2565834. DOI: 10.1371/journal.pgen.1000233. View

3.
Alon U . Network motifs: theory and experimental approaches. Nat Rev Genet. 2007; 8(6):450-61. DOI: 10.1038/nrg2102. View

4.
Batchelor E, Goulian M . Robustness and the cycle of phosphorylation and dephosphorylation in a two-component regulatory system. Proc Natl Acad Sci U S A. 2003; 100(2):691-6. PMC: 141058. DOI: 10.1073/pnas.0234782100. View

5.
Chang D, Leung S, Atkinson M, Reifler A, Forger D, Ninfa A . Building biological memory by linking positive feedback loops. Proc Natl Acad Sci U S A. 2009; 107(1):175-80. PMC: 2806707. DOI: 10.1073/pnas.0908314107. View