A New Mouse Fear Pheromone

Freaked-out mice produce a variety of airbone molecules that communicate their alarm to other mice. Researchers in Switzerland are reporting a new such fear pheromone, 2-sec-butyl-4,5-dihydrothiazole (SBT), that mice use to communicate fear among themselves (Proc. Nat. Acad. Sci. USA, DOI: 10.1073/pnas.1214249110). The team, led by Marie-Christine Broillet at the University of Lausanne, points out that the new pheromone is structurally similar to a variety of scent compounds produced by predators that also scare mice, such as 2,4,5-trimethylthiazoline (TMT), found in fox feces. SBT and TMT are heterocyclic sulfur- and nitrogen-containing molecules. Both compounds are detected by the Grue­ne­berg ganglion, a sensory organ found in mouse nostrils, near the olfaction center. The team proposes that mice may have evolved the alarm pheromone to make use of a preexisting ability to detect predator scents. They are now searching for protein receptors in the Grue­ne­berg ganglion that can detect both the pheromone and the predator scents.