Resource presentation dictates genetic and phenotypic adaptation in yeast

Area of Science:

• Evolutionary Biology
• Microbial Ecology
• Genetics

Background:

• Environmental conditions drive population adaptation, potentially causing parallelism or divergence.
• The impact of minor environmental shifts on adaptive trajectories is not well understood.

Purpose of the Study:

• To investigate how subtle environmental variations influence phenotypic and genetic adaptation in Saccharomyces cerevisiae.
• To determine if pleiotropic effects of adaptation are predictable and if genomic targets are convergent.

Main Methods:

• Evolving Saccharomyces cerevisiae populations in two distinct but 'synonymous' environments differing in sugar source presentation (glucose-galactose mixture vs. melibiose).
• Analyzing phenotypic and genomic responses to adaptation in each environment.

Main Results:

• Even minor environmental differences led to divergent phenotypic responses between yeast populations.
• Pleiotropic effects of adaptation were largely predictable despite differing adaptive pathways.
• Distinct genomic targets of adaptation were found to be functionally convergent.

Conclusions:

• Subtle environmental variations critically shape phenotypic and genetic adaptation in populations.
• Ancestor's fitness may predict pleiotropic responses, aiding in understanding adaptive outcomes.
• Further studies on diverse environments are crucial to generalize adaptive response patterns.