Evolutionary footprint of epistasis

Impact of Epistasis on Evolutionary Adaptation

Background Evolutionary adaptation is a process where a population increases its “fit” to the world it inhabits, and is often likened to climbing a hill or peak. While this process is trivial for fitness landscapes where each mutation provides an advantage (or disadvantage) to the organism that is independent of the fitness effect of a mutation on a different locus, the interaction between muta...

Evolutionary footprint of coevolving positions in genes

MOTIVATION The analysis of molecular coevolution provides information on the potential functional and structural implication of positions along DNA sequences, and several methods are available to identify coevolving positions using probabilistic or combinatorial approaches. The specific nucleotide or amino acid profile associated with the coevolution process is, however, not estimated, but only...

High-order epistasis shapes evolutionary trajectories

High-order epistasis-where the effect of a mutation is determined by interactions with two or more other mutations-makes small, but detectable, contributions to genotype-fitness maps. While epistasis between pairs of mutations is known to be an important determinant of evolutionary trajectories, the evolutionary consequences of high-order epistasis remain poorly understood. To determine the eff...

Supporting Material: Impact of Epistasis and Pleiotropy on Evolutionary Adaptation

The impact of macroscopic epistasis on long-term evolutionary dynamics.

Genetic interactions can strongly influence the fitness effects of individual mutations, yet the impact of these epistatic interactions on evolutionary dynamics remains poorly understood. Here we investigate the evolutionary role of epistasis over 50,000 generations in a well-studied laboratory evolution experiment in Escherichia coli. The extensive duration of this experiment provides a unique...