Fruit fly avoidance mechanism could lead to new ways to control pain in humans

At first, fruit flies eat like horses. Hatching inside over-ripe fruit where they were laid, they feed wildly in the sugar-rich environment until nature sends them an offer they can’t refuse. To survive, they must leave the fruit, wander off and burrow into the earth where they avoid food as if it were poison. Only then can the larvae grow and hatch into flies that will take wing to lay their own eggs.

Now, a team of researchers from the University of Georgia has discovered for the first time that the important developmental switch from food attraction to aversion in the fruit fly larva is controlled by a timing mechanism in the brain and its sensory system. The study shows how this important avoidance mechanism has been recruited into evolutionary processes to promote development and could one day lead to new methods of controlling pain in humans and other animals.

“The findings provide an intriguing glimpse into how an animal modulates its chemosensory properties and behaviors in coordination with development,” said Ping Shen, an assistant professor in the department of cellular biology at UGA and a member of the Biomedical & Health Sciences Institute. The research was published today in the journal Nature Neuroscience.

“Fruit fly larvae are like tadpoles—they have to migrate from their first habitat to stay alive and flourish,” said Shen. “What we found was that a molecular timing switch tells them when to quit eating and burrow into the earth. We also found that the same switch can trigger strong cooperative behavior in the flies.”