A Novel Role for the PKG‐encoding foraging Gene in the Fly ‘Pancreas’ of Drosophila melanogaster

Abstract

The Drosophila melanogaster corpora cardiaca (CC) is functionally homologous to the mammalian pancreatic alpha cells and anterior pituitary gland. The CC is the site of biosynthesis and secretion of the fly glucagon homolog, adipokinetic hormone (AKH). The foraging gene (for) in D. melanogaster encodes a cGMP‐dependent protein kinase (PKG) and is evolutionarily conserved across taxa. for has a well‐established role in the regulation of feeding behavior and metabolism. Here we identify a CC‐specific role for for in the regulation of adult feeding behavior, lipid metabolism, and starvation stress response. The expression of transgenic for‐RNAi constructs specifically in the CC significantly decreases adult whole body lipid content and starvation resistance, and increases adult feeding behavior. Immunohistochemistry data suggest that the transgenic manipulation of for in the CC alters the secretion of AKH. By restricting the CC‐specific transgenic manipulation of for to precise developmental periods, we demonstrate that the effects on adult metabolism and feeding behavior have their origin in juvenile life. These data demonstrate a novel role for foraging and PKG in the CC, and begin to elucidate a putative mechanism whereby juvenile experience can influence adult metabolism and health outcomes.