Mouse Wheel-Running Activity Monitoring and Analyses.

This experiment was performed using male mice (aged 2–6 mo) of the following genotypes on a C57BL6 background: WT, hPER3-WT-Tg, hPER3-P415A/H417R-Tg, and Per3^−/− (32). Mouse housing, handling, and wheel-running activity monitoring were performed as described previously (17). The activity onset and offset times were calculated using standard parameters in the ClockLab software. The default template was 6 h of inactivity followed by 6 h of activity for onsets (and vice versa for offsets). To calculate the time of onset or offset of wheel-running activity in LD 4:20, the largest 1-h increase or decrease in activity for each mouse was determined. The time designation refers to the end point of the maximal activity decrease or increase, as averaged among individual mice in each genotype. “Phase delay” is the hours of delayed-onset Zeitgeber time (ZT), calculated by comparing mutant transgenic mice with control mice. All of the mice used in this work were on a C57BL6 background except the mice shown in Fig. 2 E and F, Bottom, which were on a C57/SJL hybrid background. More information is available in SI Materials and Methods.