Evolved S. cerevisiae population sequencing

This project contains sequencing data from 90 focal populations at 6 timepoints during an evolution experiment. Abstract: "Laboratory experimental evolution provides a window into the details of the evolutionary process. To investigate the consequences of long-term adaptation, we evolved 205 S. cerevisiae populations (124 haploid and 81 diploid) for ~10,000 generations in three environments. We measured the dynamics of fitness changes over time, finding repeatable patterns of declining adaptability. Sequencing revealed that this phenotypic adaptation is coupled with a steady accumulation of mutations, widespread genetic parallelism, and historical contingency. In contrast to long-term evolution in E. coli, we do not observe long-term coexistence or populations with highly elevated mutation rates. We find that evolution in diploid populations involves both fixation of heterozygous mutations and frequent loss-of-heterozygosity events. Together, these results help distinguish aspects of evolutionary dynamics that are likely to be general features of adaptation across many systems from those that are specific to individual organisms and environmental conditions. "

本项目包含一项进化实验中90个焦点种群在6个时间点的测序数据。摘要："实验室进化实验为解析进化过程的具体细节提供了重要窗口。为探究长期适应性演化的后果，我们对205个酿酒酵母（Saccharomyces cerevisiae）种群（124个单倍体（haploid）种群与81个二倍体（diploid）种群）在三种环境下开展了约10000代的传代培养。我们测定了适合度（fitness）随时间变化的动态过程，发现了适应性下降的可重复模式。测序结果表明，该表型适应性伴随突变的持续积累、广泛的遗传平行性（genetic parallelism）与历史偶然性（historical contingency）。与大肠杆菌（Escherichia coli）的长期进化实验结果不同，本研究未观测到长期共存现象，也未发现突变率显著升高的种群。我们发现二倍体种群的进化过程同时包含杂合突变的固定以及频繁的杂合性丢失（loss-of-heterozygosity）事件。综上，这些研究结果有助于区分进化动态中可能属于多系统通用的适应性特征，以及仅局限于特定物种与环境条件的特异性特征。"