UMass Chan Medical School Faculty Publications


Shifting fitness landscapes in response to altered environments

UMMS Affiliation

Department of Biochemistry and Molecular Pharmacology; Program in Bioinformatics and Integrative Biology

Publication Date


Document Type



Adaptation, Physiological; *Environment; Evolution, Molecular; *Genetic Fitness; HSP90 Heat-Shock Proteins; Point Mutation; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; *Selection, Genetic


Computational Biology | Ecology and Evolutionary Biology | Integrative Biology | Population Biology


The role of adaptation in molecular evolution has been contentious for decades. Here, we shed light on the adaptive potential in Saccharomyces cerevisiae by presenting systematic fitness measurements for all possible point mutations in a region of Hsp90 under four environmental conditions. Under elevated salinity, we observe numerous beneficial mutations with growth advantages up to 7% relative to the wild type. All of these beneficial mutations were observed to be associated with high costs of adaptation. We thus demonstrate that an essential protein can harbor adaptive potential upon an environmental challenge, and report a remarkable fit of the data to a version of Fisher's geometric model that focuses on the fitness trade-offs between mutations in different environments. Evolution.

DOI of Published Version



Evolution. 2013 Dec;67(12):3512-22. doi: 10.1111/evo.12207. Epub 2013 Aug 2. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Journal/Book/Conference Title

Evolution; international journal of organic evolution

PubMed ID