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.
Figure 2
Phase shift behavior of Per1−/−/Pml−/−mice. Mice were entrained to a 12 h light/12 h dark cycle (LD) and a light pulse was given on the last day of LD at ZT 14 or ZT 22. (A) &(B) Phase delay response to a ZT14 light pulse (15 min) of wild type, Per1−/−, Pml−/− and Per1−/−/Pml−/− mice. (C) &(D) Phase advance response to a ZT22 light pulse (15 min) of wild type, Per1−/−, Pml−/− and Per1−/−/Pml−/− mice. Error bar indicates SEM. p < 0.05, (n = 9).
Figure 3
Average time of activity onset during LD cycles. The average time of activity onset over 14 days before ZT12 was measured for wildtype, Per1−/−, Pml−/−, Per1−/−/Pml−/− and Per2−/−/Pml−/− mice. Activity onset for Per2−/− and Per1−/− mice was previously reported by Spoelstra et al., 2004. Error bar indicates SEM. *p < 0.05, (n = 6).
Table 1
Comparison of periods and light pulse responses in mice with different genotype
| Hours (SEM) | Hours (SEM) | Hours (SEM) | |
|---|---|---|---|
| PER2/PML (n = 6) | arrhythmic | N.D. | N.D. |
Figure 4
Wheel-running behavior of Per2−/−, Pml−/−and Per2−/−/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. The marker identifies the transition from LD to DD. Light pulse (LP) is indicated by the red asterisk. Actograms are representative of (A) a wild type mouse, (B) two representative Per2−/− mice, (C) a representative Pml−/− mouse, and (D) two representative Per2−/−/Pml−/− mice. Note the level of increased activity onset prior to ZT12 in the LD cycle.