Data from: Two distinct genomic regions, harbouring the period and fruitless genes, affect male courtship song in Drosophila montana

Acoustic signals often play a significant role in pair formation and in species recognition. Determining the genetic basis of signal divergence will help to understand signal evolution by sexual selection and its role in the speciation process. An earlier study investigated QTL for male courtship song carrier frequency in Drosophila montana using microsatellite markers. We refined this study by adding to the linkage map markers for ten candidate genes known to affect song production in D. melanogaster. We also extended the analyses to additional song characters (pulse train length, pulse number, interpulse interval, pulse length and cycle number). Our results indicate that loci in two different regions of the genome control distinct features of the courtship song. Pulse train traits (pulse train length and pulse number) mapped to the X chromosome, showing significant linkage with the period gene. In contrast, characters related to song pulse properties (pulse length, cycle number and carrier frequency) mapped to the region of chromosome 2 near the candidate gene fruitless, identifying these genes as suitable loci for further investigations. In previous studies, the pulse train traits have been found to vary substantially between Drosophila species, and so are potential species recognition signals, while the pulse traits may be more important in intra-specific mate choice.

声学信号在配偶配对与物种识别中通常发挥着关键作用。阐明信号分化的遗传基础，将有助于理解性选择驱动的信号演化过程，以及其在物种形成进程中的功能。此前一项研究利用微卫星标记，对山果蝇（Drosophila montana）雄性求偶歌载波频率相关的数量性状基因座（QTL）进行了定位分析。本研究对该工作进行了优化：我们在连锁图谱中加入了10个已知可影响黑腹果蝇（Drosophila melanogaster）歌声产生的候选基因标记。此外，我们还将分析拓展至更多歌声特征维度，包括脉冲串长度、脉冲数、脉冲间隔、脉冲时长与周期数。研究结果显示，基因组内两个不同区域的基因座分别调控求偶歌的不同特征。脉冲串相关性状（脉冲串长度与脉冲数）定位至X染色体，且与周期基因（period gene）存在显著连锁关系。与之相反，与歌声脉冲特性相关的性状（脉冲时长、周期数与载波频率）则定位至2号染色体上靠近候选基因无果基因（fruitless）的区域，这表明这些基因可作为后续研究的理想靶位点。既往研究表明，不同果蝇物种间的脉冲串性状存在显著差异，因此其可能作为潜在的物种识别信号；而脉冲相关性状则更可能在种内配偶选择中发挥关键作用。