The environment affects epistatic interactions to alter the topology of an empirical fitness landscape.

ABSTRACT: The fitness effect of mutations can be influenced by their interactions with the environment, other mutations, or both. Previously, we constructed 32 ( = 2⁵) genotypes that comprise all possible combinations of the first five beneficial mutations to fix in a laboratory-evolved population of Escherichia coli. We found that (i) all five mutations were beneficial for the background on which they occurred; (ii) interactions between mutations drove a diminishing returns type epistasis, whereby epistasis became increasingly antagonistic as the expected fitness of a genotype increased; and (iii) the adaptive landscape revealed by the mutation combinations was smooth, having a single global fitness peak. Here we examine how the environment influences epistasis by determining the interactions betwe

SUBMITTER: Flynn KM 

PROVIDER: S-EPMC3616912 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature