Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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Tracking the dynamics and diversity of segmental amplification in evolving populations of Saccharomyces cerevisiae

ABSTRACT: Population adaptation to strong selection can occur through the sequential or parallel accumulation of competing beneficial mutations. The dynamics, diversity and rate of fixation of beneficial mutations within and between populations are still poorly understood. To study the changes in the mutational landscape across populations during adaptation, we performed experimental evolutions on seven parallel populations of Saccharomyces cerevisiae continuously cultured in limiting sulfate medium. By combining qPCR, array CGH, restriction, digestion and CHEF gels, and whole genome sequencing, we followed the trajectory of evolution to determine the identity and fate of beneficial mutations. Over a period of 200 generations, the yeast populations displayed parallel evolutionary dynamics that are driven by the coexistence of independent beneficial mutations. Segmental amplifications are rapidly gained under this selective pressure, including, common inverted amplifications containing the sulfate transporter gene SUL1. Detailed analysis of the populations uncovers a deep complexity where by multiple subpopulations arise and compete with each another. The most common trajectories to adaptation in these populations are incomplete soft sweeps, with adaptive variants replacing one another. These are CGH arrays. Each experiment compares the DNA content of an experimentally evolved strain with its ancestor.

ORGANISM(S): Saccharomyces cerevisiae

SUBMITTER: Maitreya Dunham

PROVIDER: E-GEOD-47854 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Tracking the dynamics and diversity of segmental amplification in evolving populations of Saccharomyces cerevisiae

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