Künstner Axel, Hoffmann Margarete, Fraser Bonnie A, Kottler Verena A, Sharma Eshita, Weigel Detlef, Dreyer Christine
Department of Molecular Biology, Max Planck Institute for Developmental Biology, Tübingen, Germany.
Guest Group Evolutionary Genomics, Max Planck Institute for Evolutionary Biology, Plön, Germany.
PLoS One. 2016 Dec 29;11(12):e0169087. doi: 10.1371/journal.pone.0169087. eCollection 2016.
For over a century, the live bearing guppy, Poecilia reticulata, has been used to study sexual selection as well as local adaptation. Natural guppy populations differ in many traits that are of intuitively adaptive significance such as ornamentation, age at maturity, brood size and body shape. Water depth, light supply, food resources and predation regime shape these traits, and barrier waterfalls often separate contrasting environments in the same river. We have assembled and annotated the genome of an inbred single female from a high-predation site in the Guanapo drainage. The final assembly comprises 731.6 Mb with a scaffold N50 of 5.3 MB. Scaffolds were mapped to linkage groups, placing 95% of the genome assembly on the 22 autosomes and the X-chromosome. To investigate genetic variation in the population used for the genome assembly, we sequenced 10 wild caught male individuals. The identified 5 million SNPs correspond to an average nucleotide diversity (π) of 0.0025. The genome assembly and SNP map provide a rich resource for investigating adaptation to different predation regimes. In addition, comparisons with the genomes of other Poeciliid species, which differ greatly in mechanisms of sex determination and maternal resource allocation, as well as comparisons to other teleost genera can begin to reveal how live bearing evolved in teleost fish.
一个多世纪以来,卵胎生的孔雀鱼(Poecilia reticulata)一直被用于研究性选择以及局部适应性。自然孔雀鱼种群在许多直观上具有适应性意义的性状上存在差异,例如装饰、成熟年龄、繁殖规模和体型。水深、光照供应、食物资源和捕食方式塑造了这些性状,而屏障瀑布常常将同一条河流中形成对比的环境分隔开来。我们已经组装并注释了来自瓜纳波排水系统一个高捕食位点的近交单雌孔雀鱼的基因组。最终组装结果包含731.6兆碱基对,支架N50为5.3兆碱基。支架被定位到连锁群上,将95%的基因组组装定位到22条常染色体和X染色体上。为了研究用于基因组组装的种群中的遗传变异,我们对10个野生捕获的雄性个体进行了测序。鉴定出的500万个单核苷酸多态性(SNP)对应的平均核苷酸多样性(π)为0.0025。该基因组组装和SNP图谱为研究对不同捕食方式的适应性提供了丰富的资源。此外,与性决定机制和母体资源分配差异很大的其他花鳉科物种的基因组进行比较,以及与其他硬骨鱼属进行比较,能够开始揭示卵胎生在硬骨鱼中的进化方式。