Comparison of ADH activity in 3-day-old wild type (CS), perS and perL flies at six time points in a 24-hour duration (ZT0, ZT4, ZT8, ZT12, ZT16, and ZT20). Each point on the line graph represents mean ADH activity +/− standard error of 3 biological replicates. ADH activity is represented as normalized absorbance units (NAU). NAU was calculated by normalizing the change in absorbance (ΔOD) due to accumulation of ADH-catalyzed NADH with the total protein concentration in each sample (BCA). X-axis is shaded clear and dark to depict light and dark conditions respectively. For each ADH activity assay five male flies were used.