Identification of a Dopamine Pathway That Regulates Sleep and Arousal in Drosophila

The dopamine pathways involved in sleep and arousal have not been well characterized. This is an elegant study using anatomically targeted genetic modifications in Drosophila to identify a specific dopamine-mediated arousal pathway. The authors found that activating a single dopamine neuron projecting to the dorsal fan-shaped body activates arousal via a DA1 receptor-mediated mechanism. They also demonstrated that this pathway is distinct from a dopamine pathway known to be involved in memory formation. These results encourage further work to identify the corresponding dopaminergic arousal pathway(s) in larger animals and humans.