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arXiv · 1207.2728

The Influence of Decoys on the Noise and Dynamics of Gene Expression

Anat Burger·Aleksandra M. Walczak·Peter G. Wolynes
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Abstract

Many transcription factors bind to DNA with a remarkable lack of specificity, so that regulatory binding sites compete with an enormous number of non-regulatory 'decoy' sites. For an auto-regulated gene, we show decoy sites decrease noise in the number of unbound proteins to a Poisson limit that results from binding and unbinding. This noise buffering is optimized for a given protein concentration when decoys have a 1/2 probability of being occupied. Decoys linearly increase the time to approach steady state and exponentially increase the time to switch epigenetically between bistable states.

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Anat Burger, Aleksandra M. Walczak, Peter G. Wolynes. 2012-07-11. The Influence of Decoys on the Noise and Dynamics of Gene Expression. https://doi.org/10.1103/physreve.86.041920

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