Insulin signalling underlies both plasticity and divergence of a reproductive trait in Drosophila.
Phenotypic plasticity is the ability of a single genotype to yield distinct phenotypes in different environments. The molecular mechanisms linking phenotypic plasticity to the evolution of heritable diversification, however, are largely unknown. Here, we show that insulin/insulin-like growth factor signalling (IIS) underlies both phenotypic plasticity and evolutionary diversification of ovariole number, a quantitative reproductive trait, in Drosophila. IIS activity levels and sensitivity have diverged between species, leading to both species-specific ovariole number and species-specific nutritional plasticity in ovariole number. Plastic range of ovariole number correlates with ecological niche, suggesting that the degree of nutritional plasticity may be an adaptive trait. This demonstrates that a plastic response conserved across animals can underlie the evolution of morphological diversity, underscoring the potential pervasiveness of plasticity as an evolutionary mechanism.
Department of Molecular and Cellular Biology, Harvard University, , 16 Divinity Avenue, Cambridge, MA 02138, USA, Department of Organismic and Evolutionary Biology, Harvard University, , 16 Divinity Avenue, Cambridge, MA 02138, USA.
Delbert A
DA
Green
Cassandra G
CG
Extavour
D000818:Animals; D004330:Drosophila / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005260:Female; D005298:Fertility; D005838:Genotype; D007328:Insulin / Q000378:metabolism*; D010053:Ovary / Q000033:anatomy & histology / Q000254:growth & development / Q000502:physiology; D010641:Phenotype; D015398:Signal Transduction; D013002:Somatomedins / Q000378:metabolism
D007328:Insulin; D013002:Somatomedins
Drosophila erecta; Drosophila sechellia; insulin receptor; ovariole; ovary; phenotypic plasticity