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Non-genetic diversity modulates population performance.

ABSTRACT: Biological functions are typically performed by groups of cells that express predominantly the same genes, yet display a continuum of phenotypes. While it is known how one genotype can generate such non-genetic diversity, it remains unclear how different phenotypes contribute to the performance of biological function at the population level. We developed a microfluidic device to simultaneously measure the phenotype and chemotactic performance of tens of thousands of individual, freely swimming Escherichia coli as they climbed a gradient of attractant. We discovered that spatial structure spontaneously emerged from initially well-mixed wild-type populations due to non-genetic diversity. By manipulating the expression of key chemotaxis proteins, we established a causal relationship between protein expression, non-genetic diversity, and performance that was theoretically predicted. This approach generated a complete phenotype-to-performance map, in which we found a nonlinear regime. We used this map to demonstrate how changing the shape of a phenotypic distribution can have as large of an effect on collective performance as changing the mean phenotype, suggesting that selection could act on both during the process of adaptation.

SUBMITTER: Waite AJ

PROVIDER: S-EPMC5199129 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Non-genetic diversity modulates population performance.

Waite Adam James AJ Frankel Nicholas W NW Dufour Yann S YS Johnston Jessica F JF Long Junjiajia J Emonet Thierry T

Molecular systems biology 20161219 12

Biological functions are typically performed by groups of cells that express predominantly the same genes, yet display a continuum of phenotypes. While it is known how one genotype can generate such non-genetic diversity, it remains unclear how different phenotypes contribute to the performance of biological function at the population level. We developed a microfluidic device to simultaneously measure the phenotype and chemotactic performance of tens of thousands of individual, freely swimming E ...[more]

PMID: 27994041

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Non-genetic diversity modulates population performance.

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Non-genetic diversity modulates population performance.

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