Monitoring Circadian Rhythms in Drosophila

Individual, 21-day-old, mated female flies were placed in glass tubes (65 mm × 5 mm) containing standard 1× SYA, and activity was recorded using the DAM System (Drosophila Activity Monitoring System; TriKinetics) as described previously [49 (link)]. Flies were entrained to a 12-hr:12-hr light:dark (LD) cycle at 25°C and 65% humidity 24–36 hr before recording. 5 days of the 12:12 hr LD cycle were recorded, followed by 5 days of a 12-hr:12-hr dark:dark (DD) cycle. Analysis of locomotor activity was performed using the fly toolbox and MATLAB software (MathWorks), as described previously [50 (link)]. Sleep was defined as a bout of inactivity lasting 5 min or more, and sleep analysis was performed with pySOLO [51 (link)]. All behavioral data (activity and sleep duration) are represented by mean values with their SEM.