Figure 1.

The Clk-GFP transgene rescues activity rhythms and expression in brain pacemaker neurons. A, w¹¹¹⁸; Clk^out (Clk^out), (w¹¹¹⁸; Clk-GFP; Clk^out), and PBac{yellow[+]-attP-9A}VK00018 (VK18, attP insertion site for Clk-GFP) flies were entrained in LD cycles for 3 d and transferred to constant darkness. Activity in constant darkness was analyzed as described in Materials and Methods. N, Number of animals tested; % Rhythmic, percentage of flies that showed significant rhythmicity; Period ± SEM, rhythm period ± SEM; Power ± SEM, rhythm power ± SEM. B, Representative actograms of flies tested in A. Flies of the indicated genotypes were entrained in LD cycles, then placed in DD for at least 7 d. The actograms show two LD cycles per line, where the second cycle on a line is the same as the first cycle on the following line. White boxes, Lights-on period; black boxes, lights-off period; gray asterisk, time when flies were placed in DD; vertical bars, fly activity. The height of vertical bars indicates relative level of activity.