Gene expression noise can promote the fixation of beneficial mutations in fluctuating environments.

ABSTRACT: Nongenetic phenotypic variation can either speed up or slow down adaptive evolution. We show that it can speed up evolution in environments where available carbon and energy sources change over time. To this end, we use an experimentally validated model of Escherichia coli growth on two alternative carbon sources, glucose and acetate. On the superior carbon source (glucose), all cells achieve high growth rates, while on the inferior carbon source (acetate) only a small fraction of the population manages to initiate growth. Consequently, populations experience a bottleneck when the environment changes from the superior to the inferior carbon source. Growth on the inferior carbon source depends on a circuit under the control of a transcription factor that is repressed in the presence of the

SUBMITTER: Schmutzer M 

PROVIDER: S-EPMC7644098 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature