Open AccessNatural sequence variants of yeast environmental sensors confer cell‐to‐cell expression variability
Author(s) -
Fehrmann Steffen,
BottinDuplus Hélène,
Leonidou Andri,
Mollereau Esther,
Barthelaix Audrey,
Wei Wu,
Steinmetz Lars M,
Yvert Gaël
Publication year - 2013
Publication title -
molecular systems biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 8.523
H-Index - 148
ISSN - 1744-4292
DOI - 10.1038/msb.2013.53
Subject(s) - biology , genetics , locus (genetics) , gene , phenotype , expression quantitative trait loci , frameshift mutation , genotype , single nucleotide polymorphism
Living systems may have evolved probabilistic bet hedging strategies that generate cell‐to‐cell phenotypic diversity in anticipation of environmental catastrophes, as opposed to adaptation via a deterministic response to environmental changes. Evolution of bet hedging assumes that genotypes segregating in natural populations modulate the level of intraclonal diversity, which so far has largely remained hypothetical. Using a fluorescent P met17 ‐GFP reporter, we mapped four genetic loci conferring to a wild yeast strain an elevated cell‐to‐cell variability in the expression of MET17 , a gene regulated by the methionine pathway. A frameshift mutation in the Erc1p transmembrane transporter, probably resulting from a release of laboratory strains from negative selection, reduced P met17 ‐GFP expression variability. At a second locus, cis ‐regulatory polymorphisms increased mean expression of the Mup1p methionine permease, causing increased expression variability in trans . These results demonstrate that an expression quantitative trait locus (eQTL) can simultaneously have a deterministic effect in cis and a probabilistic effect in trans . Our observations indicate that the evolution of transmembrane transporter genes can tune intraclonal variation and may therefore be implicated in both reactive and anticipatory strategies of adaptation.