Collaborative research: The genomics of adaptation in experimental yeast populations during short and long-term selection on invasive growth

种群如何在遗传上发生变化并适应环境条件是进化生物学、动植物育种和疾病研究中的一个基本问题。这样的基因变化在两个时间尺度上发生。在短期内，选择作用于现有的遗传变异。在更长的时间尺度上，适应需要输入和选择新的突变。新的基因组测序技术使直接观察在对新的环境条件作出反应期间发生的全基因组遗传变化成为可能。该项目将在模式微生物酿酒酵母(面包师酵母)的种群中研究侵入性生长选择过程中适应的遗传基础，这是真菌毒性的一个重要方面。新的基因组测序和分析技术将被用于识别有助于侵入性生长的变异的基因座，研究等位基因频率的变化，并识别在选择过程中发生的新突变。这项研究将提供关于全基因组遗传组成如何影响进化的新信息，这些实验集中在一种生态上重要的和与病原性的出现相关的真菌特性上。该项目将为关于进化、进化中随机和可预测过程之间的相互作用以及进化与人类健康的直接相关性的公共教育提供一个极好的案例研究。研究和推广活动将为研究生、本科生和高中生提供实验室实验、种群遗传学、基因组学和生物信息学方面的跨学科和定量培训机会。

How populations change genetically and adapt to environmental conditions is a fundamental issue in evolutionary biology, plant and animal breeding, and disease. Such genetic changes occur on two time scales. In the short term, selection acts on existing genetic variation. On longer time scales, adaptation requires the input and selection of new mutations. New genome-sequencing technologies make it possible to observe directly the genome-wide genetic changes that occur during response to novel environmental conditions. The project will study the genetic basis of adaptation during selection for invasive growth, a trait that is an important aspect of fungal virulence, in populations of the model microbe Saccharomyces cerevisiae (baker's yeast). New technologies for sequencing and analyzing genomes will be used to identify loci that contribute to variation for invasive growth, to study changes in allele frequencies, and to identify novel mutations that occur during selection.This study will provide new information about how genome-wide genetic composition both influences and is influenced by evolution in controlled, reproducible experiments that focus on a fungal trait that is ecologically important and related to emergence of pathogenicity. This project will furnish an excellent case study for public education on evolution, the interactions between random and predictable processes in evolution, and the direct relevance of evolution to human health. Research and outreach activities will provide interdisciplinary and quantitative training opportunities in laboratory experimentation, population genetics, genomics, and bioinformatics for graduate students, undergraduates, and high school students.