Figure 8. Aop and dfoxo both regulate a humoral factor, Obp99b, in the fat body.

A AOP was visualised by immunofuorescence in fat bodies of S₁106>Aop^ACT flies induced or not with RU486. In the merged image, AOP is shown in green, DAPI-stained nuclei in blue. AOP accumulates in nuclei of 26±6% of fat body cells. B Genes regulated by RU486 induction in fat bodies of S₁106>Aop^ACT flies were determined by microarray analysis and compared to changes in the fat body upon induction of S₁106>dfoxo. Mean log₂ fold change caused by induction of Aop^ACT (y-axis) is plotted against that caused by induction of dfoxo (x-axis). Genes with significant differential expression (at 20% FDR) upon induction of Aop^ACT are shown in red, dfoxo in green and both Aop^ACT and dfoxo in blue. The location of the Obp99b gene on the graph is indicated. C The levels of Obp99b mRNA in abdominal fat body mRNAs were determined relative to actin by qPCR upon RU486 induction in S₁106>Aop^ACT (n = 4) or S₁106>dfoxo (n = 8) female flies. Boxplots show log-10 derived ratios scaled to set the −RU486 condition to 0. Data were analysed using a mixed-effects linear model with genotype and RU486 as main effects and dissection batch as a random effect. Both main effects as well as their interaction were significant (p<0.01), and one-tailed t-test indicated the +RU486 condition had more Obp99b transcript for each genotype (p<0.05). D Obp99b-V5 was detected in haemolymph (1 µl) of S₁106>Obp99b-V5 female flies, fed or not RU486, or in whole-fly extracts (equivalent of half a fly) using anti-V5 antibody. The secreted IMP-L2 protein was used as a loading control.