Fig. 5

Caffeine triggers c-fos expression more strongly in dbh F0 KOs. a Sleep traces for dbh F0 KO and control-injected larvae exposed to either caffeine or water. The post-drug rebound sleep period of a is summarised for each larva in b (upper chart). Caffeine treatment had a strong boosting effect on rebound sleep in both control-injected and dbh F0 KO larvae (lower chart). The caffeine effect size is not significantly different between the two genotypes. c qRT-PCR on groups of ~ 15 larvae revealed that each group of dbh F0 KO larvae treated with caffeine (n = 3 biological replicates) showed greater relative c-fos expression than the groups of control larvae treated with caffeine (n = 3 biological replicates); see also Fig. S9a. Each square is the mean of triplicate technical replicates. d There is a weak positive correlation between c-fos expression and subsequent rebound sleep levels (R2 = 0.62), but water-treated dbh F0 KO larvae do not conform to this correlation, showing high sleep levels despite low c-fos expression