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Enhancement of the stability of genetic switches by overlapping upstream regulatory domains

Patrick B. Warren·Pieter Rein ten Wolde
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Abstract

We study genetic switches formed from pairs of mutually repressing operons. The switch stability is characterised by a well defined lifetime which grows sub-exponentially with the number of copies of the most-expressed transcription factor, in the regime accessible by our numerical simulations. The stability can be markedly enhanced by a suitable choice of overlap between the upstream regulatory domains. Our results suggest that robustness against biochemical noise can provide a selection pressure that drives operons, that regulate each other, together in the course of evolution.

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Patrick B. Warren, Pieter Rein ten Wolde. 2003-11-01. Enhancement of the stability of genetic switches by overlapping upstream regulatory domains. https://doi.org/10.1103/physrevlett.92.128101

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