Eau de fruit fly
A single scent moves female fruit files to swoon and males to flee. The difference, new research shows, is in the brain’s wiring.
Male flies on the prowl put out a pheromone called cis-vaccenyl acetate (cVA) that both sexes detect with scent-sensing cells on their antennae.
To explain how cVA prompts such different reactions in male and female flies, researchers traced the circuitry of the cells connecting the antennae to the brain. In the brain, the cells branch out and make connections with other neurons. The researchers discovered that wiring between the cVA–detecting cells and the brain is different in males than in females.
This difference may affect how the cVA message travels through the brain, enabling the flies to react to pheromones with sex-specific behaviors, says Robert Datta, a neuroscientist at Columbia University in New York. He and colleague Maria Luisa Vasconcelos led the study, which appeared online in Nature Feb. 27.
A gene called fruitless determines mating behavior and controls the wiring of the cVA–sensing cells. Females genetically engineered with the male version of fruitless turn to prudes, uninterested in mating. Their brains resemble those of male flies. Male flies without the gene court other males, and their cVA–sensing brain cells take on the female pattern.