Figure 2.

The zebrafish testis clock ticks in a cell-specific manner. (a and b) Bioluminescence recordings (a) and their periods (b) of the testis cultured ex vivo from Tg(per3: luc) (black), Tg(per3: luc); clock1a^−/− (red) and Tg(bmal1b: luc) (cyan), detrended by 24-hour moving average (n = 10). (c) Locomotor rhythm analysis of 5- to 9-dpf (days postfertilization) WT (black) and clock1a^−/− (red) zebrafish larvae under DD condition (n = 24). (d) Detrended bioluminescence of Tg(per3: luc) testis recordings under 10-hour advanced conditions after the culture ex vivo for 3 days under normal LD (n = 4). (e) Confocal images of the testis from clock1a-KI-tdTomato zebrafish (n = 3). (f) Confocal images of IHC staining in clock1a^−/− and WT control testes with a mouse CLOCK antibody (n = 6). (g and h) Expression of per1b and per2 in the Sertoli cells (g) and spermatogonia (h), and their downregulation in the clock1a^−/− Sertoli cells or spermatogonia, as shown by confocal images of the testes from the Tg(per1b: EGFP; gsdf: mCherry), Tg(per1b: EGFP; gsdf: mCherry); clock1a^−/−, Tg(per2: EGFP; gsdf: mCherry), and Tg(per2: EGFP; gsdf: mCherry); clock1a^−/− zebrafish lines (n = 5–14). In (e–h), all nuclei were counterstained with Hoechst 33342. Arrowheads indicate Sertoli cells, and arrows spermatogonia. Scale bars =100 μm (Fig. S2 and Movie S1).