Fig. 7
Ecdysone suppression of Inka cell secretory competence reduces ETH levels in hemolymph of stressed flies. a Ecdysone levels were determined by enzyme immunoassay (EIA) from unstressed/fed flies 24 h after heat stress or 24 h after starvation (n = 15 flies per point; each point represents a separate experiment). b, c ETH levels were determined by EIA from hemolymph extractions of unstressed mated females or 24 h after heat stress (b, see Additional file 10: Figure S4E) and after 24 h of sugar starvation (c, see Additional file 10: Figure S4F) (n = 50 flies per point; each point represents a separate experiment). d Volume of ETH immunoreactivity in A4 Inka cells from saline- or 20-hydroxyecdysone (20E)-injected females (n = 20). e ETH-like immunoreactivity of Inka cells (green) observed in ETH-Gal4/UAS-Red Stinger females 24 h after injection of either saline (e) or 36 ng of 20E (e’) (scale bars = 10 μm). f–h Heat-stressed females of genotypes ETH-Gal4;Tubulin-Gal80ts/UAS-ßFTZ-F1, ETH-Gal4;Tubulin-Gal80ts/UAS-EcR-DN, ETH-Gal4;Tubulin-Gal80ts/UAS-EcR-RNAi, and genetic controls scored for oogenesis (f) stages 8–9 progressing (green), degenerating (red), and late stage (10–13) oocytes (blue), (g) egg retention, and (h) eggs laid during the 3 days after heat stress (n = 30) (biological replicates). Error bars represent SEM. NS, p > 0.05; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001