PMID:21802129

Citation	Poelwijk, FJ, de Vos, MG and Tans, SJ (2011) Tradeoffs and optimality in the evolution of gene regulation. Cell 146:462-70
Abstract	Cellular regulation is believed to evolve in response to environmental variability. However, this has been difficult to test directly. Here, we show that a gene regulation system evolves to the optimal regulatory response when challenged with variable environments. We engineered a genetic module subject to regulation by the lac repressor (LacI) in E. coli, whose expression is beneficial in one environmental condition and detrimental in another. Measured tradeoffs in fitness between environments predict the competition between regulatory phenotypes. We show that regulatory evolution in adverse environments is delayed at specific boundaries in the phenotype space of the regulatory LacI protein. Once this constraint is relieved by mutation, adaptation proceeds toward the optimum, yielding LacI with an altered allosteric mechanism that enables an opposite response to its regulatory ligand IPTG. Our results indicate that regulatory evolution can be understood in terms of tradeoff optimization theory.
Links	PubMed Online version:10.1016/j.cell.2011.06.035
Keywords	Allosteric Regulation; Biological Evolution; Escherichia coli/genetics; Escherichia coli Proteins/metabolism; Gene Expression Regulation, Bacterial; Genetic Fitness; Isopropyl Thiogalactoside/metabolism; Lac Operon; Lac Repressors/metabolism; Mutation
edit table

Significance

You can help EcoliWiki by summarizing why this paper is useful

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Add links to pages that link here (e.g. gene, product, method pages)

See Help:References for how to manage references in EcoliWiki.