Adaptation is the process whereby a population or species becomes better fitted to its habitat, through modifications of various life-history traits which can be positively or negatively correlated. The molecular factors underlying these co-variations remain to be elucidated. Using Saccharomyces cerevisiae as a model system, we have investigated effects of varying the dosage of genes involved in the transformation of resources into energy on life-history traits. Changing gene dosage for each of three glycolytic enzyme genes (hexokinase 2, phosphoglucose isomerase and fructose 1,6-bisphosphate aldolase) resulted in variation of enzyme activities, glucose consumption rate, and life-history traits (growth rate, carrying capacity and cell size). However, the range of effects depended on which enzyme is expressed differently. Most interestingly, these changes revealed a genetic trade-off between carrying capacity and cell size, supporting the discovery of two extreme life-history strategies already described in yeast populations. The "ants", which have lower glycolytic gene dosage, uptake glucose slowly and have a small cell size but reach a high carrying capacity, whereas the "grasshoppers", which have higher glycolytic gene dosage, consume glucose more rapidly, allocate it to a larger cell size but reach a lower carrying capacity. These results demonstrate antagonist pleiotropy for glycolytic genes and show that altered dosage of a single gene drives a switch between two life-history strategies in yeast.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Annotation Extension||Reference|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Assay||Construct||Conditions||Strain Background||Reference|