dSir2 in the fat body and muscles regulates glucose homeostasis. An oral glucose tolerance test (oGTT) was performed using hemolymph isolated from pSw-MHC-Gal4/Sir2EP2300 (mdSir2OE) (A), pSw-MHC-Gal4; UAS-Sir2RNAi (mdSir2KD) (B), pSw-S1106-Gal4/Sir2EP2300 (fbdSir2OE) (C), and pSw-S1106-Gal4; UAS-Sir2RNAi (fbdSir2KD) (D) flies. For every time point, 5 samples from hemolymph isolated from 12 flies each were used. Control, −RU486; overexpression/knockdown, +RU486 (200 μM). All data are shown as means ± standard errors of the means. *, P < 0.05; **, P < 0.01; ***, P < 0.001.