mortality/aging
N |
• Background Sensitivity: on mixed background, survival to weaning age and beyond is not different from wild-type littermates
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homeostasis/metabolism
• the mean body temperature of homozygotes is significantly lower than controls
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• mutants show disruption of circadian thermoregulation; nocturnal elevations of core body temperature are intermittent, with pronounced dusk and dawn elevations but no sustained elevation between them, in contrast to controls which showed elevated, organized, and sustained core temperatures
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behavior/neurological
• homozygotes are significantly hypokinetic compared to heterozygotes or wild-type, as assessed by wheel-running and general activity
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• when transferred to free-running conditions (continuous darkness, DD), wild-type and heterozygous mice exhibit precise circadian profiles, while homozygotes no longer display burst of activity associated with lights-off
• free-running (DD) activity is less coherent and precise relative to wild-type mice, for wheel-running and general activity
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• significantly reduced activity early during the night (dark phase), although brief burst of activity at onset of dark phase, compared to heterozygotes or wild-type which show increased activity beginning at night onset and activity is sustained through most of the night; consolidated locomotor activity during early night typical of normal mice is absent in mutants
• mutants show a much greater degree of activity, comparable to the other genotypes during the late stage of the dark phase
• this activity is observed in N2F1 mice, as well and N4F2 mice, indicating that it is not influenced by background; also, if mice are entrained to a skeleton photoperiod with two 1 hour light pulses at dusk and dawn, the abnormal phase behavior is observed
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