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bioRxiv · 10.1101/137810

Cellular Adaptation Through Fitness-Directed Transcriptional Tuning

Freddolino, P. L.·Yang, J.·Tavazoie, S.
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Abstract

Cells adapt to changes in their environment through transcriptional responses that are hard-coded in their regulatory networks. Such dedicated pathways, however, may be inadequate for adaptation to novel or extreme environments. We propose the existence of a fitness optimization mechanism that tunes the global transcriptional output of a genome to match arbitrary external conditions in the absence of dedicated gene-regulatory networks. We provide evidence for the proposed tuning mechanism in the adaptation of Saccharomyces cerevisiae to laboratory-engineered environments that are foreign to its native gene-regulatory network. We show that transcriptional tuning operates locally at individual gene promoters and its efficacy is modulated by genetic perturbations to chromatin modification machinery.

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Freddolino, P. L., Yang, J., Tavazoie, S.. 2017-05-14. Cellular Adaptation Through Fitness-Directed Transcriptional Tuning. https://doi.org/10.1101/137810

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