Phenotypic plasticity as an adaptation to a functional trade-off
Abstract
We report the evolution of a phenotypically plastic behavior that circumvents the hardwired trade-off that exists when resources are partitioned between growth and motility in Escherichia coli. We propagated cultures in a cyclical environment, alternating between growth up to carrying capacity and selection for chemotaxis. Initial adaptations boosted overall swimming speed at the expense of growth. The effect of the trade-off was subsequently eased through a change in behavior; while individual cells reduced motility during exponential growth, the faction of the population that was motile increased as the carrying capacity was approached. This plastic behavior was produced by a single amino acid replacement in FliA, a regulatory protein central to the chemotaxis network. Our results illustrate how phenotypic plasticity potentiates evolvability by opening up new regions of the adaptive landscape.
Article and author information
Author details
Funding
University of Minnesota (Research Support)
- Xiao Yi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Wenying Shou, Fred Hutchinson Cancer Research Center, United States
Version history
- Received: July 1, 2016
- Accepted: September 28, 2016
- Accepted Manuscript published: October 3, 2016 (version 1)
- Version of Record published: October 11, 2016 (version 2)
- Version of Record updated: October 13, 2016 (version 3)
Copyright
© 2016, Yi & Dean
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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