Fig 4. Period dissociation in LL detected by long tern recording of RWA.

A. Initial responses of RWA to transition from LD12:12 cycle to LL. Two representative actograms from each genotype are shown. B, C, D. Examples of long term RWA in WT, mPer2^Luc/Luc, and Per2^+/Luc mice, respectively. All animals were entrained to LD12:12 prior release into LL. Wild type animals (B) show the expected range of periods (all >24 h in LL); whereas homozygous mPer2^Luc/Luc mice (C) show dual rhythms (<24 h and >24 h in LL). (D) Heterozygous mPer2^+/Luc mice exhibit individual variance with patterns ranging between the wild type and mutant characteristics, as well as unpredictable arrhythmicity over time in LL. E. Period analysis of rhythm from the 3 genotypes in the first 7 days following transition from LD to LL. Red, Green, Blue symbols indicate significant periods of individual mice from each of the three genotypes. Closed symbols indicate the higher amplitude rhythm. Open symbols indicate a second significant rhythm with lower amplitude. No significant genotype differences were found among either long periods or short periods. F. Expression of short (<24 h) and long (>24 h) periods in LL determined 12 weeks following entry into LL (symbols shown as described in 4F). No significant differences between genotypes as in 4E. Long and short periods were significantly different within genotype for both mPer2^Luc/Luc and Per2^+/Luc.