Figure 2.

A selection of rhythmic clock-target genes regulated in the early stages of zebrafish larval development. A Nanostring-based gene expression analysis of a wide selection of genes examined between 72–168 h post-fertilization. The selected data shown in panels a, b and c reveals a wide range of genes that show robust oscillations during embryo development, when larvae are raised on a light-dark cycle. Constant light (in red) stops the circadian pacemaker in the embryo, as well as the rhythmic expression in downstream, clock-regulated genes. (a) shows that numerous cell cycle regulators have robust transcriptional daily rhythms. (b) shows changes in three genes involved in neuro-development and differentiation, with neuroD showing very high amplitude rhtyhms. (c) shows rhythms in three genes involved in cell fate decisions in the intestine. (d) shows how neuroD only begins to show robust oscillations from day 4–5 of development onwards. (Taken from Laranjeiro and Whitmore, 2014) [26].