Related Experiment Video
Updated: May 5, 2026
15:09
Flow Cytometry-based Purification of S. cerevisiae Zygotes
Published on: September 21, 2012
12.0K
Ancient evolutionary trade-offs between yeast ploidy states
Enikö Zörgö1, Karolina Chwialkowska, Arne B Gjuvsland
1Centre for Integrative Genetics, Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, UMB, Ås, Norway.
Plos Genetics
|April 5, 2013
Summary
Ploidy, the number of chromosome sets, significantly impacts yeast reproduction across diverse environments. These ploidy-environment interactions are ancient, suggesting strong evolutionary selection and multiple molecular underpinnings.
Area of Science:
- Evolutionary biology
- Genetics
- Microbiology
Background:
- Ploidy, the number of chromosome sets in a nucleus, is a key genetic variable.
- Its evolutionary significance and impact on fitness across different environments are not well understood.
Purpose of the Study:
- To investigate the influence of ploidy on the mitotic fitness of yeast species.
- To explore how ploidy-environment interactions shape evolutionary trajectories.
Main Methods:
- Comparative analysis of ploidy effects on fitness in Saccharomyces cerevisiae and Saccharomyces paradoxus.
- Examination of genotypic and phenotypic variation across natural populations.
- Molecular investigation of genetic factors influencing ploidy-environment interactions.
Main Results:
- Ploidy significantly influences reproductive fitness, with environment-specific effects being common.
- These interactions are conserved across millions of years, indicating strong selection.
- Cell size and mating type locus composition explain a portion of these interactions.
- Genetic variation, such as in ion transporters, can reverse the relative advantages of different ploidy levels.
Conclusions:
- Ploidy and ecology engage in a dynamic interplay with significant evolutionary consequences.
- Previous hypotheses on general ploidy advantages were too simplistic.
- Multiple molecular mechanisms underlie these complex interactions.
Related Concept Videos
01:28Yeast Signaling
15.7K
Yeasts are single-celled organisms, but unlike bacteria, they are eukaryotes (cells with a nucleus). Cell signaling in yeast is similar to signaling in other eukaryotic cells. A ligand, such as a protein or a small molecule released from a yeast cell, attaches to a receptor on the cell surface. The binding stimulates second-messenger kinases to activate or inactivate transcription factors that further regulate gene expression. Many of the yeast intracellular signaling cascades have similar...
15.7K
01:49Meiosis I
176.7K
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by...
176.7K
01:29Nondisjunction
68.0K
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
68.0K
03:09Meiosis I
30.8K
Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of meiosis, where the genetic recombination of homologous chromosomes and the reduction of the ploidy level by half occurs.
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
30.8K
02:57Meiosis vs. Mitosis
39.5K
Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, meiosis causes the division of germ cells and plays an essential role in sexual reproduction. Due to their unique functional requirements, mitosis and meiosis differ from each other in multiple aspects.
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
Before the start of mitosis and meiosis I, the cell synthesizes DNA, resulting in two homologous copies of each chromosome. DNA synthesis is...
39.5K
01:21Nondisjunction
4.5K
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold...
4.5K