Data from: Too much of a good thing: The unique and repeated paths toward copper adaptation

We isolated and identified adaptive mutations soon after they arose, reducing the number of neutral mutations, to determine the first genetic steps that yeast take when adapting to copper. We analyzed 34 such strains through whole-genome sequencing and by assaying fitness within different environments; we also isolated a subset of mutations through tetrad analysis of four lines. We identified a multi-layered evolutionary response.

In total, 57 single base-pair mutations were identified across the 34 lines. In addition, gene amplification of the copper metallothionein protein, CUP1, was rampant, as was chromosomal aneuploidy. Four other genes received multiple, independent mutations in different lines (the vacuolar transporter genes VTC1 and VTC4; the plasma membrane H+-ATPase PMA1; and MAM3, a protein required for normal mitochondrial morphology).

Analyses indicated that mutations in all four genes, as well as CUP1 copy number, contributed significantly to explaining variation in copper tolerance. Our study thus finds that evolution takes both common and less trodden pathways toward evolving tolerance to an essential, but highly toxic, micronutrient.

Usage notes

Data package about copper adaptation in yeast This package contains files and scripts related to the publication "Too much of a good thing: The unique and repeated paths toward copper adaptation". Raw data and analyses are included. DryadSubmission.zip