Dilley, L.C. et al. eLife (2020) https://doi.org/10.7554/eLife.52676

The younger the animal, the longer it sleeps. That youngsters need more shut eye than their elders is likely related to the heavy demands of their developing nervous system—disrupted sleep in children can lead to neurocognitive problems as they become adults. The molecular underpinnings for such observations, however, remain unknown.

Day-old Drosophila also sleep more than more mature 4–5 day old fruit flies, and the insects lend themselves to high-throughput molecular screens. Using an RNAi screen, researchers at the Perelman School of Medicine at the University of Pennsylvania identify a gene that appears to be required for sleep maturation in the flies: Pdm3, a transcription factor involved in the wiring of dopaminergic neurites, which promote wakefulness, to areas of the brain that promote sleep. Young flies in which pdm3 is knocked down don’t sleep as much as they should.