Figure 1.

Dopaminergic Signaling Is Required in MVP2 Neurons for Appetitive LTM

(A and B) In (A), constitutive downregulation of DAMB in MVP2 neurons impaired appetitive LTM (n = 16), F(2, 45) = 9.25, p < 0.001; whereas in (B), constitutive downregulation of DAMB in MVP2 neurons did not affect 2-hr memory (n = 14), F(2, 39) = 0.69, p = 0.51. Similar results were observed using a second non-overlapping DAMB RNAi (see Figures S1A and S1B). Inhibition of any of the other D1-like dopamine receptors (dDA1 and DopEcR) in MVP2 did not affect LTM (see Figures S1C and S1D).

(C and D) In (C), downregulation of DAMB in MVP2 adult neurons impaired LTM (n = 10), F(2, 27) = 6.67, p < 0.005; whereas non-induced controls displayed normal LTM (see Figure S1C). (D) Downregulation of DAMB in MVP2 adult neurons did not affect 2-hr memory (n = 12), F(2, 33) = 0.20, p = 0.82.

(E and F) In (E), constitutive downregulation of the D2-like dopaminergic receptor dD2R in MVP2 neurons impaired appetitive LTM (n = 16), F(2, 45) = 8.07, p < 0.01. However, unlike DAMB, dD2R downregulation also impaired 2-hr memory, as shown in (F) (n = 11), F(2, 30) = 5.30, p < 0.05.

(G and H) In (G), downregulation of dD2R in MVP2 adult neurons impaired LTM (n = 17), F(2, 49) = 4.87, p < 0.05; whereas non-induced controls displayed normal LTM (see Figure S1F). (H) Downregulation of dD2R in MVP2 adult neurons affected 2-hr memory (n = 18), F(2, 51) = 8.74, p < 0.001.

Error bars indicate mean ± SEM. Statistical tests were performed using one-way ANOVA. ^∗p < 0.05; ^∗∗p < 0.01, in post hoc comparison; ns, not significant. See Table S1 for sugar perception and olfactory acuity controls.