Figure 4.

Reduction in sleep rebound following thermogenetic sleep deprivation extends to sleep depth/arousal threshold but is not observed following mechanical sleep deprivation. (A) Arousal threshold for the control MI00386/+ and lines with low sleep rebound, MI00323/+ and MI00393/+, under undeprived conditions (Cntrl) or after thermogenetic sleep deprivation (Sleep Dep). Mechanical stimulus was applied at Zeitgeber time (ZT)23, 2 h after the temperature was returned to 21°C for the sleep deprived groups. Flies that were asleep at the time the stimulus was applied were marked as responding if they showed movement within 2 min following stimulus. Plotted data are the mean and range of fraction of flies awoken in four independent experiments (n = 12–32 sleeping flies in each experiment). A two-way analysis of variance with experimental run as an additional blocking variable indicates main effects of sleep deprivation and genotype on arousal threshold as well as a significant interaction between sleep deprivation and genotype, P < 0.05. Tukey honest significant difference test is used for individual comparisons between groups in post hoc analysis. (B) Sleep rebound following mechanical sleep deprivation for the lines identified as hits from the thermogenetic sleep deprivation screen, with comparison to MI00386/+ as a control. Data are plotted ± standard error of the mean from three combined experiments, n = 24–32 per genotype in each experiment. No significant reduction of sleep rebound is observed for either MI00323/+ or MI00393/+ in three of three experiments assessed by Welch t-test, P < 0.05.