Institut de Biologie du Developpement de Marseille-Luminy, Aix-Marseille Université, Marseille, France.
PLoS One. 2012;7(8):e43888. doi: 10.1371/journal.pone.0043888. Epub 2012 Aug 30.
In Drosophila, male flies perform innate, stereotyped courtship behavior. This innate behavior evolves rapidly between fly species, and is likely to have contributed to reproductive isolation and species divergence. We currently understand little about the neurobiological and genetic mechanisms that contributed to the evolution of courtship behavior. Here we describe a novel behavioral difference between the two closely related species D. yakuba and D. santomea: the frequency of wing rowing during courtship. During courtship, D. santomea males repeatedly rotate their wing blades to face forward and then back (rowing), while D. yakuba males rarely row their wings. We found little intraspecific variation in the frequency of wing rowing for both species. We exploited multiplexed shotgun genotyping (MSG) to genotype two backcross populations with a single lane of Illumina sequencing. We performed quantitative trait locus (QTL) mapping using the ancestry information estimated by MSG and found that the species difference in wing rowing mapped to four or five genetically separable regions. We found no evidence that these loci display epistasis. The identified loci all act in the same direction and can account for most of the species difference.
在果蝇中，雄性果蝇表现出先天的、刻板的求偶行为。这种先天行为在不同的果蝇物种之间迅速进化，很可能促成了生殖隔离和物种分化。我们目前对促成求偶行为进化的神经生物学和遗传机制知之甚少。在这里，我们描述了两个密切相关的物种 D. yakuba 和 D. santomea 之间的一种新的行为差异：求偶过程中的翅膀划动频率。在求偶过程中，D. santomea 雄蝇反复将翅膀叶片旋转到面向前方，然后再向后（划动），而 D. yakuba 雄蝇很少划动翅膀。我们发现这两个物种的翅膀划动频率在种内几乎没有变化。我们利用多重散弹枪基因分型（MSG）在单条 Illumina 测序的两个回交群体中进行基因分型。我们利用 MSG 估计的祖先信息进行数量性状基因座（QTL）作图，发现翅膀划动的物种差异映射到四个或五个在遗传上可分离的区域。我们没有发现这些位点存在上位性的证据。鉴定出的位点都朝着同一个方向作用，可以解释大部分的物种差异。
