Fig. 7.

Validation of AstC-R2 expression in insulin producing cells. Experimental validation of the presence of an undecribed isoform of allostatin receptor (AstC-R2) in a well characterized cell type, insulin producing cells, for which GAL4 driver lines are available enabling fluorescence co-localization of the receptor in the aforementioned neurons. a Featureplot of mature neurons. Among peptidergic clusters (circled) cells with robust expression of insuline like peptides Ilp2, Ilp3 and Ilp5 are colored in purple. IPCs: Insulin producing cells. b Maximum-intensity projection of the confocal stack of a brain in which the IPCs are labeled with a fluorescent HaloTag ligand (Magenta) and AstC-R2 mRNA is co-detected by FISH (green), bar 10 µm. Dashed lines outline area where the single z plane is shown on the left panels, bar 5 µm. c Dotplot showing the enriched expression of Ilp2, Ilp3, Ilp5 and AstC-R2 in peptidergic cluster 49 compared to the remaining peptidergic clusters (numering as in Fig. 1b). d Anatomy of insulin-producing cells (IPCs). The IPCs are a group of 7 bilaterally symmetrical neurons receiving input coveying the nutritional state of the animal through their dendrites (boxed, bottom). To respond, they release insulin-like peptides (Ilp2, Ilp3, Ilp5) through their axons (boxed, top), which synapse onto the ring gland, a major secretory organ responsible for homeostatic balance in Drosophila