Fig. 6.

In vitro addition of PDF stabilizes PER in fly brains. Same experiment was performed as in Fig. 4, except that 10 µM PDF peptide instead of Sp-cAMPS was added to the AHL. Brains were dissected at ZT22 in AHL with peptide and drug as indicated in the figure. The brains were incubated for 6 h until ZT4 before and fixed. (A) PER staining (magenta) in PDF cells (green). (Scale bar: 20 µm.) (B) PER signal in PDF cells was quantified. Data were analyzed as in Fig. 4. The bars in the histogram indicate the mean relative PER intensity. The number of brain hemispheres tested in two independent experiments is indicated by “n.” Error bars represent ±SEM. The triple asterisk (***) represents P < 0.001, and “n.s.” represents no statistical significance as determined by one-way ANOVA, Turkey post hoc test.