1. Non-genetic diversity modulates population performance.
- Author
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Waite, Adam James, Frankel, Nicholas W, Dufour, Yann S, Johnston, Jessica F, Long, Junjiajia, and Emonet, Thierry
- Subjects
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ESCHERICHIA coli , *CELL motility , *CHEMOTAXIS , *JENSEN'S inequality , *STABILITY of nonlinear systems , *BIOLOGICAL adaptation , *BACTERIA - 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. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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