Fitness effects of altering gene expression noise in Saccharomyces cerevisiae
- University of Michigan, United States
Abstract
Gene expression noise is an evolvable property of biological systems that describes differences in expression among genetically identical cells in the same environment. Prior work has shown that expression noise is heritable and can be shaped by selection, but the impact of variation in expression noise on organismal fitness has proven difficult to measure. Here, we quantify the fitness effects of altering expression noise for the TDH3 gene in Saccharomyces cerevisiae. We show that increases in expression noise can be deleterious or beneficial depending on the difference between the average expression level of a genotype and the expression level maximizing fitness. We also show that a simple model relating single-cell expression levels to population growth produces patterns consistent with our empirical data. We use this model to explore a broad range of average expression levels and expression noise, providing additional insight into the fitness effects of variation in expression noise.
Data availability
Flow data (FCS files) used to quantify fluorescence levels produced by the 43 TDH3 promoter alleles are available in the FlowRepository (flowrepository.org) under experiment ID FR-FCM-ZY8Y.Raw bright field and fluorescence images, as well as bright field images where cell division events were annotated, are available on Zenodo (https://zenodo.org) with DOI 10.5281/zenodo.1327545All other data are provided as source data and/or supplementary files with the manuscript.
Article and author information
Author details
Patricia J Wittkopp
Funding
National Institutes of Health (R01GM108826)
- Patricia J Wittkopp
European Molecular Biology Organization (EMBO ALTF 1114-2012)
- Brian PH Metzger
National Science Foundation (CB-1021398)
- Patricia J Wittkopp
National Institutes of Health (1F32GM115198)
- Andrea Hodgins-Davis
National Institutes of Health (R35GM118073)
- Patricia J Wittkopp
National Institutes of Health (T32 HG000040)
- Brian PH Metzger
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Duveau et al.
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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Fitness effects of altering gene expression noise in Saccharomyces cerevisiae
eLife 7:e37272.
https://doi.org/10.7554/eLife.37272
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