Figure 1: Flies form water-reward LTM.
From: Neural circuits for long-term water-reward memory processing in thirsty Drosophila
(a) Olfactory memory curve after water conditioning in wild-type flies. After a single training session, different fly populations were tested once for water memory 0 (3 min), 1, 3, 6, 12, 24 and 32 h after training. Each value represents mean±s.e.m. (N=9, 8, 8, 8, 8, 8 and 7 from left to right points). P>0.05; analysis of variance (ANOVA). (b) PPK28 is required for 3-min, 3-h and 24-h water-reward memories. Genotypes are wild-type (WT) and ppk28 mutant flies, respectively. Each value represents mean±s.e.m. (N=8, 8, 10, 10, 8 and 8 from left to right bars). *P<0.05; t-test. (c) Flies were either fed 35 mM CXM in dry sucrose (+CXM) or dry sucrose alone (−CXM) during the water-deprivation period before and after training (see Methods). Different fly populations were tested once for 3-min, 3-h or 24-h memory. Each value represents mean±s.e.m. (N=8 for each bar). *P<0.05; t-test. (d) The 3-min and 3-h memories were unaffected by crammer (cer), tequila (teq), or radish (rsh) mutations. 24-h memory performances of crammer, tequila and radish mutant flies were significantly different from those of wild-type (WT) flies. Each value represents mean±s.e.m. (N=9, 8, 8, 8, 12, 8, 8, 8, 11, 8, 9 and 8 from left to right bars). *P<0.05; ANOVA followed by Tukey’s test. (e) Adult-stage-specific expression of the dCREB2-b repressor in MBs abolished 24-h memory, leaving 3-min and 3-h memory intact. Left panel, the R13F02-GAL4 expression pattern (green). The brain was immunostained using DLG antibody (magenta). Scale bar, 50 μm. Each value represents mean±s.e.m. (N=8 for each bar). *P<0.05; ANOVA followed by Tukey’s test.
