Single-cell in vivo imaging of cellular circadian oscillators in zebrafish

The circadian clock is a cell-autonomous time-keeping mechanism established gradually during embryonic development. Here, we generated a transgenic zebrafish line carrying a destabilized fluorescent protein driven by the promoter of a core clock gene, nr1d1, to report in vivo circadian rhythm at the single-cell level. By time-lapse imaging of this fish line and 3D reconstruction, we observed the sequential initiation of the reporter expression...