LAUSR

Mutations at the Darkener of Apricot (Doa) locus of Drosophila melanogaster alter sexual differentiation by disrupting sex-specific splicing of doublesex pre-mRNA, a key regulator of sex determination. Here, we study the effect of seven Doa alleles and several trans-heterozygous combinations on pheromones and courtship behavior. The cuticular hydrocarbon (CHC) profile was slightly masculinized in females, with an accumulation of shorter compounds (C23 and C25) and a reduction in longer compounds (C27 and C29). The profile was feminized in males. Female cuticular profiles showed fewer dienes and female pheromones in six alleles and in the trans-heterozygotes and showed more male pheromones (tricosene and pentacosene) in three alleles (DEM, E786 and HD) and in all trans-heterozygotes. Courtship was severely affected in Doa males; in particular, males made fewer copulation attempts and copulated less with both control and Doa females. These results suggest that Doa could modulate pheromone production and sex behavior by altering sexual differentiation in the cuticle and the nervous system.