FIGURE 5.

Nocturnal activity bouts of the different strains at short photoperiods (photoperiods between 6 and 12 h). The same normalized activity profiles shown in Figures 1, 2 are plotted in a way that the night is centered. In (A) are shown per⁰ uas-per; per⁰ clk4.1-gal4 uas-per; per⁰ clk4.1-gal4 uas-per; per⁰ Pdf-gal4 uas-per; and per⁰ Pdf-gal80 mai-gal4 uas-per; whereas in (B), per⁰ mai-gal4 uas-per; per⁰ clk4.1-gal4 mai-gal4 uas-per; per⁰ tim-gal4 uas-per; and WT_CantonS are shown. Black arrows indicate times at which nocturnal activity is reduced. Otherwise, the labeling is similar to Figures 1, 2. Flies with PER in the M-DN show a lower M activity than flies with PER in the M-LN. Therefore, in these flies, it is more difficult to distinguish M activity from general nocturnal (N) activity and we added a question mark to the M peak. In flies with PER in M-, E-LN, and M-DN, N activity appeared absent and only the early M peak was visible, whereas in wild-type flies, N and M activity appeared largely suppressed. The latter is indicated by two black arrowheads.