Figure 13

Comparison of behavioral phase for intact flies with that of luciferase-reported tim expression for whole animals and isolated body parts. (a) Rhythms of subject types given on the ordinate of the upper-left plot; all types except the top one involved luminescence rhythms. Mean signals are plotted for each (across flies or tissue specimens): behavior, n = 6; whole fly luciferase activity (live fly), n = 10; dissected antennae, n = 16; heads, n = 14; wings, n=15; bpdies (fly segnents posterior to the head), n = 15; legs, n = 24. In each case, the mean signal was smoothed with a 4-hour low-pass filter and normalized. In addition, the behavioral plot was been adjusted by binning the data, so that these average-locomotion plots are normalized against total activity events per hour. This behavioral rhythm (averaged for the 6 flies) shows two peaks, one at lights-on (0, 24, 48...), another at lights-off (12 hours later). The five luciferase rhythms exhibited early-morning peaks, albeit not all at identical times. Some of these molecular timecourses are smooth; others are noisy; and although some display high amplitudes while others do not, it is important to note that the strength of rhythmicity is obtained from the regularity of the data, not merely the amplitude of the oscillation. (b) Mean phase values determined for the entirety of the 144-hour (6-days) records in (a) are plotted over time for each whole-fly or dissected-specimen group. Note that the behavioral signal has been split into two components for this presentation: beh(m) is the morning peak near times of lights-on; beh(e), evening peak near lights-off. (c) Phase data in (b) re-plotted in polar coordinates on a unit circle. The direction of a given line extending from the center indicates the phase-time in hours, and the length of that line the consistency of the peak times over the 6-day timecourse. Whereas the average luciferase signals were quite consistent temporally (including on consecutive days), the behavioral peaks, especially the morning ones, were more variable.