Natural variation in food acquisition mediatedviaaDrosophilacGMP-dependent protein kinase

Abstract

SUMMARYIn natural environments where food abundance and quality can change drastically over time, animals must continuously alter their food acquisition strategies. Although genetic variation contributes to this plasticity, the specific genes involved and their interactions with the environment are poorly understood. Here we report that natural variation in the Drosophilagene, foraging (for), which encodes a cGMP-dependent protein kinase (PKG), affects larval food acquisition in an environmentally dependent fashion. When food is plentiful, the wild-type rover(forR) allele confers lower food intake and higher glucose absorption than both the wild-type sitter (fors) allele and the mutant fors2 allele. When food is scarce, forR, fors and fors2 larvae increase food intake to a common maximal level, but forRlarvae retain their increased absorption efficiency. Changes in forexpression can induce corrective behavioral modifications in response to food deprivation. When reared in environments with low food levels, forR larvae have higher survivorship and faster development than fors and fors2larvae. Together, these results show that natural variation in forhas far reaching implications affecting a suite of phenotypes involved in the regulation of food acquisition.