FIGURE 3.

miR-279 regulates the circadian rhythm in Drosophila.(A)Schematic showing the molecular mechanisms of central clock neurons to downstream neurons in order to regulate the rest/activity cycle. The central clock neurons release PDF which is sensed via the pdf receptor in target cells. Upon PDF receptor activation, the expression of the cytokine Unpaired is activated, but also repressed via the microRNA miR-279. The released cytokine is bound by the receptor DOME in central clock downstream neurons which eventually assure the transition between rest and activity in the circadian rhythm of the fly. (B) During the day a wildtype fly shows alternating patterns of activity and rest. During daytime the fly shows high activity which is indicated by the high bars in the activity plot. During the night the rest cycle starts, indicated by low bars. The microRNA-279 mutant flies do not show rest/activity cycles anymore and show a overall activity throughout day and night.