Octopamine mediates protein-seeking behavior in mated female Drosophila

a Schematic illustration of the DAMS-based locomotion assay. Briefly, virgin female flies were collected shortly after eclosion and raised in the presence of sucrose and yeast extract (S？+？YE) for 3–5 days. Afterwards, female flies were either mated with males for 1 day or kept as virgins. These mated or virgin females were then transferred individually to polycarbonate tubes (5？mm (D)？×？65？mm (L)) and assayed in DAMS. b Midline-crossing activity in 30-min bins of wild-type Canton-S-mated female flies assayed in the presence of 5% sucrose alone (“S”, light orange) or 5% sucrose plus 2% yeast extract (“S？+？YE”, dark orange) (n？=？49–53). Yellow bars represent light-on period of 12？h in this and all other figures. c Average daily midline-crossing activity of flies assayed in b (n？=？49–53). d Average daily midline-crossing activity of flies assayed in b from Day 1 to Day 4 (n？=？49–53). e–g Average daily midline-crossing activity of flies assayed on different protein-rich food types (n？=？38–41, 58–69, 24–28, respectively). h, i Midline-crossing activity in 30-min bins of wild-type Canton-S male flies (h) and virgin female flies (i) assayed in the presence of 5% sucrose alone (“S”, light orange) or 5% sucrose plus 2% yeast extract (“S？+？YE”, dark orange) (n？=？44–53). j Schematic illustration of the video recording-based locomotion assay. Briefly, individual flies were introduced into a behavioral chamber in the presence of a small food patch located in the center, and their positions and behaviors were recorded and analyzed by a custom computer program. k Spatial distribution of protein-deprived Canton-S flies assayed in the presence of sucrose (left) or sucrose plus yeast extract (right) (the heat maps showed the average duration for flies to stay in each pixel; n？=？13 (left) and 17 (right); for SEM see Supplementary Fig. S5). Color temperature represents average time spent on each pixel for the duration of the assay (11？h). l Total walking distance of protein-deprived flies assayed in i (n？=？13 and 17). m On-food and off-food walking speed of protein-deprived flies assayed in i (n？=？13 and 17). n A summary of the behavioral analysis. Briefly, protein deprivation enhances flies’ protein-seeking behavior, by increasing their tendency to approach protein-rich food, to reduce their movement during their visits to protein-rich food, and to reduce their willingness to leave protein-rich food. o–v Average daily midline-crossing activity of flies assayed in S and S？+？YE food (o, n？=？27–42; p, n？=？26–32; q, n？=？28–39; r, n？=？25–33; s, n？=？44–55; t, n？=？22–32; u,