Figure 1

Wheel-running behavior of Per1 ^−/− /Pml ^−/− mice. The wheel-running actograms are double plotted showing a 12 h light/12 h dark cycle (LD) and a free-running period of 12 h dark/12 h dark (DD) cycles. Transition from LD to DD is indicated by the marker. Actograms are representative of (A) a wild type mouse, a Per1 ^−/−, a Pml ^−/− and a Per1 ^−/− / Pml ^−/− mouse. (B) Summary of periods obtained from wild type (n = 7) and Per1 ^−/− / Pml ^−/− (n = 12) mice over 1–20, 20–40 and 40–60 days in a free-running environment. Error bar indicates SEM.* p < 0.05.