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关键作用。解析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及其在物种形成过程中的作用。此前一项研究利用微卫星标记，对蒙氏果蝇（Drosophila montana）雄性求偶歌载波频率的数量性状基因座（Quantitative Trait Locus, QTL）进行了定位分析。本研究对该工作进行了优化：在连锁图谱中加入了10个已知可影响黑腹果蝇（Drosophila melanogaster）鸣曲产生的候选基因标记。同时，我们将分析拓展至更多鸣曲特征，包括脉冲列长度、脉冲数量、脉冲间隔、脉冲时长与周期数。研究结果显示，基因组两个不同区域的基因座分别调控求偶歌的不同特征。脉冲列性状（脉冲列长度与脉冲数量）被定位至X染色体，且与周期基因（period gene）存在显著连锁关系。与之相反，与鸣曲脉冲特性相关的特征（脉冲时长、周期数与载波频率）被定位至2号染色体上靠近候选基因fruitless的区域，提示上述基因可作为后续研究的理想靶点。既往研究发现，脉冲列性状在不同果蝇物种间存在显著差异，因此可作为潜在的物种识别信号；而脉冲性状则在种内配偶选择中发挥更为关键的作用。