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Genomic convergence toward diploidy in Saccharomyces cerevisiae.

ABSTRACT: Genome size, a fundamental aspect of any organism, is subject to a variety of mutational and selection pressures. We investigated genome size evolution in haploid, diploid, and tetraploid initially isogenic lines of the yeast Saccharomyces cerevisiae. Over the course of approximately 1,800 generations of mitotic division, we observed convergence toward diploid DNA content in all replicate lines. This convergence was observed in both unstressful and stressful environments, although the rate of convergence was dependent on initial ploidy and evolutionary environment. Comparative genomic hybridization with microarrays revealed nearly euploid DNA content by the end of the experiment. As the vegetative life cycle of S. cerevisiae is predominantly diploid, this experiment provides evidence that genome size evolution is constrained, with selection favouring the genomic content typical of the yeast's evolutionary past.

SUBMITTER: Gerstein AC

PROVIDER: S-EPMC1570378 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Genomic convergence toward diploidy in Saccharomyces cerevisiae.

Gerstein Aleeza C AC Chun Hye-Jung E HJ Grant Alex A Otto Sarah P SP

PLoS genetics 20060901 9

Genome size, a fundamental aspect of any organism, is subject to a variety of mutational and selection pressures. We investigated genome size evolution in haploid, diploid, and tetraploid initially isogenic lines of the yeast Saccharomyces cerevisiae. Over the course of approximately 1,800 generations of mitotic division, we observed convergence toward diploid DNA content in all replicate lines. This convergence was observed in both unstressful and stressful environments, although the rate of co ...[more]

PMID: 17002497

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Dataset Information

Genomic convergence toward diploidy in Saccharomyces cerevisiae.

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Genomic convergence toward diploidy in Saccharomyces cerevisiae.

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