Document Type
Article
Publication Title
Genomics
Publication Date
12-2014
Volume
104
Issue
6
Disciplines
Biology | Life Sciences
Abstract
The fitness landscape is a powerful metaphor for describing the relationship between genotype and phenotype for a population under selection. However, empirical data as to the topography of fitness landscapes are limited, owing to difficulties in measuring fitness for large numbers of genotypes under any condition. We previously reported a case of reciprocal sign epistasis (RSE), where two mutations individually increased yeast fitness in a glucose-limited environment, but reduced fitness when combined, suggesting the existence of two peaks on the fitness landscape. We sought to determine whether a ridge connected these peaks so that populations founded by one mutant could reach the peak created by the other, avoiding the low-fitness "Valley-of-Death" between them. Sequencing clones after 250 generations of further evolution provided no evidence for such a ridge, but did reveal many presumptive beneficial mutations, adding to a growing body of evidence that clonal interference pervades evolving microbial populations.
Keywords
Epistasis, Evolution, Genomics, Yeast
DOI
https://doi.org/10.1016/j.ygeno.2014.10.011
Rights
© 2014 Elsevier Inc. All rights reserved.
Recommended Citation
Kami E. Chiotti, Daniel J. Kvitek, Karen H. Schmidt, Gregory Koniges, Katja Schwartz, Elizabeth A. Donckels, Frank Rosenzweig, Gavin Sherlock, The Valley-of-Death: Reciprocal sign epistasis constrains adaptive trajectories in a constant, nutrient limiting environment, Genomics, Volume 104, Issue 6, Part A, 2014, Pages 431-437, https://doi.org/10.1016/j.ygeno.2014.10.011