Cis-regulatory divergence of eloF drives reproductive isolation in Drosophila

The differential production of pheromones is a major barrier to mating between species in Drosophila. Individuals from morphologically similar sister species can produce different sets of cuticular hydrocarbons that allow potential mates to identify them as a suitable partner. In order to elucidate cis-regulatory mechanisms behind speciation, we looked for allele-specific expression in hydrocarbon-producing oenocytes from F1 hybrids of the sister species D. simulans and D. sechellia. By focusing on cis-regulatory changes specific to female oenocytes, we rapidly identified a small number of candidate genes. Oour RNA-seq approach proved to be far more efficient than QTL mapping in identifying candidate genes, and it can be used to pinpoint the genetic basis for a wide range of traits differing due to cis-regulatory divergence between any interfertile species. mRNA profiles of male and female oenocytes and fat bodies were generated from F1 hybrid D. sechellia x D. simulans flies, by deep sequencing, in duplicate, using Illumina HiSeq 2000