Dataset Information

Negative auto-regulation increases the input dynamic-range of the arabinose system of Escherichia coli.

ABSTRACT:

Background

Gene regulation networks are made of recurring regulatory patterns, called network motifs. One of the most common network motifs is negative auto-regulation, in which a transcription factor represses its own production. Negative auto-regulation has several potential functions: it can shorten the response time (time to reach halfway to steady-state), stabilize expression against noise, and linearize the gene's input-output response curve. This latter function of negative auto-regulation, which increases the range of input signals over which downstream genes respond, has been studied by theory and synthetic gene circuits. Here we ask whether negative auto-regulation preserves this function also in the context of a natural system, where it is embedded within many additional interactions. To address this, we studied the negative auto-regulation motif in the arabinose utilization system of Escherichia coli, in which negative auto-regulation is part of a complex regulatory network.

Results

We find that when negative auto-regulation is disrupted by placing the regulator araC under constitutive expression, the input dynamic range of the arabinose system is reduced by 10-fold. The apparent Hill coefficient of the induction curve changes from about n = 1 with negative auto-regulation, to about n = 2 when it is disrupted. We present a mathematical model that describes how negative auto-regulation can increase input dynamic-range, by coupling the transcription factor protein level to the input signal.

Conclusions

Here we demonstrate that the negative auto-regulation motif in the native arabinose system of Escherichia coli increases the range of arabinose signals over which the system can respond. In this way, negative auto-regulation may help to increase the input dynamic-range while maintaining the specificity of cooperative regulatory systems. This function may contribute to explaining the common occurrence of negative auto-regulation in biological systems.

SUBMITTER: Madar D

PROVIDER: S-EPMC3163201 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Publications

Negative auto-regulation increases the input dynamic-range of the arabinose system of Escherichia coli.

Madar Daniel D Dekel Erez E Bren Anat A Alon Uri U

BMC systems biology 20110712

<h4>Background</h4>Gene regulation networks are made of recurring regulatory patterns, called network motifs. One of the most common network motifs is negative auto-regulation, in which a transcription factor represses its own production. Negative auto-regulation has several potential functions: it can shorten the response time (time to reach halfway to steady-state), stabilize expression against noise, and linearize the gene's input-output response curve. This latter function of negative auto-r ...[more]

PMID: 21749723

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Dataset Information

Negative auto-regulation increases the input dynamic-range of the arabinose system of Escherichia coli.

Background

Results

Conclusions

Publications

Negative auto-regulation increases the input dynamic-range of the arabinose system of Escherichia coli.

Similar Datasets

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