We tested the hypothesis that the time course of the evolution of antifungal drug resistance depends on the ploidy of the fungus. The experiments were designed to measure the initial response to the selection imposed by the antifungal drug fluconazole up to and including the fixation of the first resistance mutation in populations of Saccharomyces cerevisiae. Under conditions of low drug concen...

X chromosomes are unusual in many regards, not least of which is their nonrandom gene content. The causes of this bias are commonly discussed in the context of sexual antagonism and the avoidance of activity in the male germline. Here, we examine the notion that, at least in some taxa, functionally biased gene content may more profoundly be shaped by limits imposed on gene expression owing to h...

The line value of a genotype is defined as the expected value of all lines that can be derived from this genotype. Specific genetic effects are defined for this value: only additive and additive by additive epistatic effects are necessary. There is no dominance effect for such a value. A general expression for the covariances between related lines is given. From a design with several lines per ...

Analyses of diverse eukaryotes reveal that genomes are dynamic, sometimes dramatically so. In numerous lineages across the eukaryotic tree of life, DNA content varies within individuals throughout life cycles and among individuals within species. Discovery of examples of genome dynamism is accelerating as genome sequences are completed from diverse eukaryotes. Though much is known about genomes...

Four caffeine-resistant haploid isolates, two resistant to 50 mM caffeine and two resistant to 100 mM caffeine, were genetically analyzed. Complementation and tetrad analysis indicated that all four mutations are alleles of the same locus. All four isolates demonstrated incomplete dominance when hybridized to the wild-type strain and dominance of high to low resistance when hybridized to one an...

Culturing haploid strains of Saccharomyces cerevisiae in liquid minimal medium with 2% ethanol and 2% leucine resulted in the formation of long anucleate pseudohyphae. This occurred only with the combination of ethanol as carbon source and leucine as nitrogen source and was independent of mating type. The transition to a pseudohyphal form observed under these conditions appears to be irreversib...

It has long been appreciated that aneuploidy - in which cells possess a karyotype that is not a multiple of the haploid complement - has a substantial impact on human health, but its effects at the subcellular level have only recently become a focus of investigation. Here, we summarize new findings characterizing the impact of aneuploidy on protein quality control. Because aneuploidy has been a...

Much of the work on finite populations with overlapping generations has been limited to deriving effective population numbers with the tacit assumption that the dynamics of the population will be similar to a population with nonoverlapping generations and the appropriate population number. In this paper, some exact and approximate results will be presented on the behavior of the first two momen...

We reformulate the eigenvalue problem for the selection-mutation equilibrium distribution in the case of a haploid asexually reproduced population in the form of an equation for an unknown probability generating function of this distribution. The special form of this equation in the infinite sequence limit allows us to obtain analytically the steady state distributions for a number of particula...