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Title: A Theoretical Lower Bound for Selection on the Expression Levels of Proteins

Abstract

We use simple models of the costs and benefits of microbial gene expression to show that changing a protein's expression away from its optimum by 2-fold should reduce fitness by at least [Formula: see text], where P is the fraction the cell's protein that the gene accounts for. As microbial genes are usually expressed at above 5 parts per million, and effective population sizes are likely to be above 10(6), this implies that 2-fold changes to gene expression levels are under strong selection, as [Formula: see text], where Ne is the effective population size and s is the selection coefficient. Thus, most gene duplications should be selected against. On the other hand, we predict that for most genes, small changes in the expression will be effectively neutral.

Authors:
 [1];  [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Genomics and Systems Biology
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1379417
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Genome Biology and Evolution
Additional Journal Information:
Journal Volume: 8; Journal Issue: 6; Journal ID: ISSN 1759-6653
Publisher:
Society for Molecular Biology and Evolution
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 60 APPLIED LIFE SCIENCES; gene expression levels; metabolic models; microbiology

Citation Formats

Price, Morgan N., and Arkin, Adam P. A Theoretical Lower Bound for Selection on the Expression Levels of Proteins. United States: N. p., 2016. Web. doi:10.1093/gbe/evw126.
Price, Morgan N., & Arkin, Adam P. A Theoretical Lower Bound for Selection on the Expression Levels of Proteins. United States. doi:10.1093/gbe/evw126.
Price, Morgan N., and Arkin, Adam P. 2016. "A Theoretical Lower Bound for Selection on the Expression Levels of Proteins". United States. doi:10.1093/gbe/evw126. https://www.osti.gov/servlets/purl/1379417.
@article{osti_1379417,
title = {A Theoretical Lower Bound for Selection on the Expression Levels of Proteins},
author = {Price, Morgan N. and Arkin, Adam P.},
abstractNote = {We use simple models of the costs and benefits of microbial gene expression to show that changing a protein's expression away from its optimum by 2-fold should reduce fitness by at least [Formula: see text], where P is the fraction the cell's protein that the gene accounts for. As microbial genes are usually expressed at above 5 parts per million, and effective population sizes are likely to be above 10(6), this implies that 2-fold changes to gene expression levels are under strong selection, as [Formula: see text], where Ne is the effective population size and s is the selection coefficient. Thus, most gene duplications should be selected against. On the other hand, we predict that for most genes, small changes in the expression will be effectively neutral.},
doi = {10.1093/gbe/evw126},
journal = {Genome Biology and Evolution},
number = 6,
volume = 8,
place = {United States},
year = 2016,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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