![Reducing dopamine signaling impairs learning. (A) 3-Iodo-l-tyrosine (3IY)-fed flies display an increase in sleep compared with vehicle-fed controls (Sleep in minutes per hour, n = 20–21 flies/group, two-way repeated-measures ANOVA for drug × time F[23,782] = 5.49, p < 10−6). (B) 3IY-fed flies display more total sleep than age-matched vehicle-fed siblings (*p < 10–6, t-test). (C) 3IY increased average daytime sleep bout duration (*p < 0.001, t-test). (D) 3IY did not impair waking activity compared with vehicle-fed controls (*p < 0.01, t-test). (E) Vehicle-fed Cs controls displayed spatial learning. (F) In contrast to vehicle-fed flies, 3IY-fed Cs flies were impaired in spatial learning. (n = 8 flies/group, two-way ANOVA drug × trial, F[9,126] = 2.33, p < 0.05). (G) Learning index of 3IY-fed flies was greatly reduced compared with vehicle-fed controls (*p < 0.01, t-test). (H) Schematic of temperature-shift experiment for sleep. Sleep is recorded over 24 h of 5-day-old TH-GAL4/+, tubpGAl80ts, UAS Kir/+, and TH-GAL4/+ > tubpGAl80ts, UAS Kir/+ flies maintained at 18°C and of their sibling flies that are reared for 3 days at 18°C, and then shifted to the elevated temperature of 30°C for 2 days prior to testing. (I) TH-GAL4/+>GAL80ts, UAS Kir/+ flies displayed an increase in sleep at 30°C compared with siblings maintained at 18°C; sleep in TH-GAL4/+ or the tubP GAL80ts, UAS Kir/+ parental controls was similar at both 18°C and 30°C (n = 20–30 flies/group, two-way ANOVA for genotype × temperature, F[2,131] = 7.28, p < 0.01; *p < 0.001, modified Bonferroni test). (J) Schematic of temperature-shift experiment for learning. Spatial learning is evaluated in 5-day-old TH-GAL4/+, tubpGAl80ts, UAS Kir/+, and TH-GAL4/+ > tubpGAl80ts, UAS Kir/+ flies maintained at 18°C and of their sibling flies that are reared for 3 days at 18°C, and then shifted to the elevated temperature of 30°C for 2 days prior to testing. (K) Spatial learning is impaired in TH>GAL80ts, UAS Kir flies at 30°C compared with siblings maintained at 18°C; temperature did not impact spatial learning in either TH-GAL4/+ or the tubP GAL80ts, UAS Kir/+ parental controls (n = 8–12 flies/group, Two-way ANOVA for genotype × temperature, F[2,116] = 4.96, p < 0.01, *p < 0.05, modified Bonferroni test).](https://oup.silverchair-cdn.com/oup/backfile/Content_public/Journal/sleep/44/3/10.1093_sleep_zsaa197/2/zsaa197_fig6.jpeg?Expires=1749707814&Signature=kqSPgr2rl7i-npbzlwKgvV02xCygHEAmqiAMlbKCKz6QSP8VZGr~dnfaD5PDYkpLIQnCvhzJmfcgGxzLTZ76Kp190-2ucrh4sP08YI3xW8eV~5o2uvjvv5X-fUhDVYGhV1o3IWbCNeW66ZRRZedTNfXxiroAp9x9PDNDm24IzlYN6FI2VqOanTJHmDB4pp54LgdP2w5oIMr9xX1XTHs2HareJv3lDUCrg2Pe0SsOkjeIY2Js4e9UQEIQxl0a66UEZlsIxyDi7lGh5Iamt5iDYFzaJKC6PD6foW3j~gn9cCI-bVqQEAxi9UM617UuJ710rBoKlRHw59FkUC96vYlbPg__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Reducing dopamine signaling impairs learning. (A) 3-Iodo-l-tyrosine (3IY)-fed flies display an increase in sleep compared with vehicle-fed controls (Sleep in minutes per hour, n = 20–21 flies/group, two-way repeated-measures ANOVA for drug × time F[23,782] = 5.49, p < 10−6). (B) 3IY-fed flies display more total sleep than age-matched vehicle-fed siblings (*p < 10–6, t-test). (C) 3IY increased average daytime sleep bout duration (*p < 0.001, t-test). (D) 3IY did not impair waking activity compared with vehicle-fed controls (*p < 0.01, t-test). (E) Vehicle-fed Cs controls displayed spatial learning. (F) In contrast to vehicle-fed flies, 3IY-fed Cs flies were impaired in spatial learning. (n = 8 flies/group, two-way ANOVA drug × trial, F[9,126] = 2.33, p < 0.05). (G) Learning index of 3IY-fed flies was greatly reduced compared with vehicle-fed controls (*p < 0.01, t-test). (H) Schematic of temperature-shift experiment for sleep. Sleep is recorded over 24 h of 5-day-old TH-GAL4/+, tubpGAl80ts, UAS Kir/+, and TH-GAL4/+ > tubpGAl80ts, UAS Kir/+ flies maintained at 18°C and of their sibling flies that are reared for 3 days at 18°C, and then shifted to the elevated temperature of 30°C for 2 days prior to testing. (I) TH-GAL4/+>GAL80ts, UAS Kir/+ flies displayed an increase in sleep at 30°C compared with siblings maintained at 18°C; sleep in TH-GAL4/+ or the tubP GAL80ts, UAS Kir/+ parental controls was similar at both 18°C and 30°C (n = 20–30 flies/group, two-way ANOVA for genotype × temperature, F[2,131] = 7.28, p < 0.01; *p < 0.001, modified Bonferroni test). (J) Schematic of temperature-shift experiment for learning. Spatial learning is evaluated in 5-day-old TH-GAL4/+, tubpGAl80ts, UAS Kir/+, and TH-GAL4/+ > tubpGAl80ts, UAS Kir/+ flies maintained at 18°C and of their sibling flies that are reared for 3 days at 18°C, and then shifted to the elevated temperature of 30°C for 2 days prior to testing. (K) Spatial learning is impaired in TH>GAL80ts, UAS Kir flies at 30°C compared with siblings maintained at 18°C; temperature did not impact spatial learning in either TH-GAL4/+ or the tubP GAL80ts, UAS Kir/+ parental controls (n = 8–12 flies/group, Two-way ANOVA for genotype × temperature, F[2,116] = 4.96, p < 0.01, *p < 0.05, modified Bonferroni test).
