Confinement stress with movement restriction suppresses male courtship in Drosophila through dopamine-dependent neuroplasticity

Stress disturbs the physiological and psychological balance in animals, leading to changes in brain function. Here, we show that stress in a small space with movement restriction (SS stress) suppresses male courtship in Drosophila and that alterations in dopamine signaling induced by SS stress are responsible for the persistence of this suppression after the stress experience. We found that SS stress activates numerous dopamine neurons in the brain. Pharmacological and genetic analyses revealed that dopamine synthesis, release, and reception are essential for the persistence of SS-stress-induced courtship suppression. A specific subset of dopamine neurons projects to the mushroom body (MB), a brain region where various sensory inputs are integrated. We identified that SS-stress-induced dopamine release plastically depresses the activity of a subset of MB neurons, and this neuronal depression contributes to the sustained suppression of male courtship behavior following stress exposure. This novel stress model using Drosophila provides valuable insights into dopamine-mediated stress mechanisms, particularly those related to confined spaces.