Ligand for the CCHamide-2 receptor CCHa2-R (PubMed:23293632, PubMed:21110953). In one study, shown to be an orexigenic peptide which induces appetite and stimulates food intake, leading to the release of insulin-like peptides which stimulate growth (PubMed:26168160). In another study, shown to be a nutrient-sensitive peptide derived from peripheral tissues which controls growth by directly regulating the production and release of insulin-like peptides (PubMed:26020940). Expressed in endocrine cells of the larval midgut (at protein level) (PubMed:24098432, PubMed:24850274). Also expressed in endocrine cells of the midgut of adult males and females (at protein level) (PubMed:24098432). In the midgut, expression occurs mainly in the anterior region (at protein level) (PubMed:24098432). In the larval central nervous system, expressed in about 40 neurons in the brain hemispheres and ventral nerve cord (at protein level) (PubMed:24098432). Highly expressed in larval and adult gut with low levels in larval and adult brain (PubMed:24098432). Very little expression in the larval fat body (PubMed:26168160). However, another study shows high levels of expression in the larval fat body as well as the larval gut with low levels in the larval central nervous system (PubMed:26020940). Very low expression in eggs. Expression increases during the first instar larval stage, decreases gradually during the second and third instar larval stages and in pupae and increases in adults. Repressed in larvae by starvation for 18 hours with levels recovering when larvae are refed with yeast or glucose. Reduced food intake in adults and larvae, reduced locomotor activity, delayed development with mutants taking 200 hours to develop from egg to pupa compared to 130 hours for wild-type flies, reduced levels of the insulin-like peptides Ilp2 and Ilp3, and reduced wing size (PubMed:26168160). Reduced levels of insulin-like peptide Ilp5 and reduced body weight of mid-third instar larvae (PubMed:26020940).