Department of Electrical & Computer Engineering, University of California, San Diego, La Jolla, CA, USA.
Division of Respiratory Medicine, Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA.
Nat Commun. 2021 Feb 12;12(1):997. doi: 10.1038/s41467-021-21281-6.
To detect the genomic mechanisms underlying evolutionary dynamics of adaptation in sexually reproducing organisms, we analyze multigenerational whole genome sequences of Drosophila melanogaster adapting to extreme O conditions over an experiment conducted for nearly two decades. We develop methods to analyze time-series genomics data and predict adaptive mechanisms. Here, we report a remarkable level of synchronicity in both hard and soft selective sweeps in replicate populations as well as the arrival of favorable de novo mutations that constitute a few asynchronized sweeps. We additionally make direct experimental observations of rare recombination events that combine multiple alleles on to a single, better-adapted haplotype. Based on the analyses of the genes in genomic intervals, we provide a deeper insight into the mechanisms of genome adaptation that allow complex organisms to survive harsh environments.
为了检测有性繁殖生物适应进化动态的基因组机制，我们分析了在近 20 年的实验中适应极端 O 条件的黑腹果蝇的多代全基因组序列。我们开发了分析时间序列基因组学数据和预测适应性机制的方法。在这里，我们报告了在重复种群中硬选择和软选择扫荡的惊人同步性水平，以及有利的新出现突变的出现，这些突变构成了少数几个不同步的扫荡。我们还对罕见的重组事件进行了直接的实验观察，这些事件将多个等位基因组合成一个单一的、适应性更好的单倍型。基于对基因组区间内基因的分析，我们深入了解了允许复杂生物在恶劣环境中生存的基因组适应机制。
