Data from: Distinct developmental mechanisms influence sexual dimorphisms in the milkweed bug Oncopeltus fasciatus

Sexual dimorphism is common in animals. The most complete model of sex
determination comes from Drosophila melanogaster, where the relative
dosage of autosomes and X chromosomes leads indirectly to sex-specific
transcripts of doublesex (dsx). Female Dsx interacts with a mediator
complex protein encoded by intersex to activate female development. In
males the transcription factor encoded by fruitless promotes male-specific
behavior. The genetics of sex determination have been examined in a small
number of other insects, yet several questions remain about the
plesiomorphic state. Is doublesex required for female and male
development? Is fruitless conserved in male behavior or morphology? Are
other components such as intersex functionally conserved? To address these
questions, we report the expression and functional tests of doublesex,
intersex and fruitless in the hemipteran Oncopeltus fasciatus,
characterizing three sexual dimorphisms. doublesex prevents intersex
phenotypes in all sexes and dimorphic traits in the milkweed bug. intersex
and fruitless are expressed across the body, in females and males.
fruitless and intersex also affect the genitalia of both sexes but have
effects limited to different dimorphic structures in different sexes.
These results reveal roles for intersex and fruitless distinct from other
insects and demonstrate distinct development mechanisms in different
sexually dimorphic structures.