Figure 4.

Reduced sleep in p{dmper/M2M1} flies continues even during extended constant light conditions where circadian clock function is abolished. Shown are group averages of locomotor activity (A,B) and sleep profiles (C,D) for either p{dmper/8:8} (WT; black line) or p{dmper/M2M1} (black dashed line) male flies at 18°C. Flies were entrained for 5 days in LD. Subsequently, one group was placed in constant darkness (DD), whereas another group was placed in constant light (LL). For each genotype and entrainment condition, data from at least 16 flies was used to generate the profiles shown. White, black, dark gray, and light gray horizontal bars denote periods of light, dark, “subjective daytime” in DD, and “subjective nighttime” in LL, respectively.