Figure 6. Insulin release in flies with altered OA signalling.

Immunohistochemical analysis of dILP2 levels in the ILP-producing cells of the pars intercerebralis of Tβh^nM18 males and females as well as their matching controls under normal food conditions (A,B,E) as well as following a short period (24 h) of starvation (C,D,F). Representative immunohistochemical pictures (A–D) and a quantitative evaluation (E,F) are shown. Ectopic activation of OA release (Tβh-Gal4) by heat in TrpA1 (UAS-TrpA1)-expressing cells (G, left) or by blue light in channelrhodopsin-2 (UAS-ChR2)-expressing cells (G, right). Effect of exogenously applied OA on relative dILP2 concentrations in ILP-producing cells of control as well as of Tβh^nM18 flies (H). Direct measurement of insulin released into the haemolymph (I) and total insulin levels (K) using flies carrying HA- and FLAG-tagged-dILP2. Mean values of at least five different experiments ± SEM are shown. *p < 0.05, **p < 0.01 and ***p < 0.001.