Figure 1. Dopamine elevates cAMP and PKA across multiple MB lobes.
(A) Confocal image (single z plane) showing YFP fluorescence from the MB of a 238Y-GAL4>UAS-epac-camps fly. Regions of interest were placed at multiple levels of the α/β neurons (α tip, upper stalk, lower stalk), the heel, and the γ lobe (not visible at this plane of section). D: dorsal, L: lateral.
(B) A confocal image of the YFP fluorescence from the MB α/β neurons of a c739-GAL4>UAS-epac-camps fly, oriented as in panel A.
(C) Increases in cAMP observed in several regions of the MB following application of 100 μM dopamine in the bath in 238Y-GAL4>UAS-epac-camps flies (n ≥ 11). Lines and shaded regions represent the mean and S.E.M, respectively.
D) Increases in cAMP observed in several regions of the MB following application of 1 mM dopamine in the bath (n ≥ 11). Colors and lines are the same as in panel C.
(E) cAMP responses following application of 100 μM dopamine in the α and β lobes of c739-GAL4>UAS-epac-camps flies (n = 8) in the presence and absence of 100 μM SCH-23390.
(F) Dose-response curves showing the cAMP responses across multiple regions of interest in the MB to dopamine in 238Y-GAL4>UAS-epac-camps flies (n ≥ 8).
(G) Dose-response curves showing the cAMP responses across multiple regions of interest in the MB to dopamine in c739-GAL4>UAS-epac-camps flies (n ≥ 8).
(H) cAMP responses from the α and β lobes were inhibited by the addition of SCH-23390 in the bath in c739-GAL4>UAS-epac-camps flies (n = 8). The three concentrations were applied sequentially, and the responses recorded 10 min apart. There was a significant main effect of treatment (p < 0.001; two-way repeated-measures ANOVA). *p < 0.05, **p < 0.01, ***p<0.001 (Sidak), relative to the pre-application response magnitudes.
(I) Dose-response curves showing the PKA responses across multiple regions of interest in the MB to dopamine in 238Y-GAL4>UAS-AKAR3 flies (n = 11 for concentrations ≥ 10−6 M, n = 6 for subthreshold concentrations).
(J) Normalized dose-response curves for the data in panel I.
(K) Quantification of the logEC50 of the AKAR3 responses to dopamine. *p < 0.05 (Tukey).