How Do Fruit Flies Smell Food?
WouterResearchers at Caltech have been exploring the nature of smell and olfaction in fruit flies for years. One of the most intriguing findings involves the way flies sense CO2. Insects have olfactory organs called sensilla, which are located on the antennae. The RIKEN Center for Biosystems Dynamics has recently studied the development and function of sensilla, as well as the gene that drives its development.
Flies have a sophisticated olfactory sense, and their antennae contain olfactory sensory nerve cells. Odours are absorbed through these cells, which allow flies to detect odors up to seven kilometres away. These neurons send signals down the sensillum and into the brain. This incredible ability helps flies detect and react to food and odors, enabling them to avoid predators and survive in their environment.
The study was published in the journal Chemical Senses, where the research team reported their findings. They concluded that the odor of sucrose increased the appetite of the fly three times, even when it was not exposed to the odorant itself. However, it is not yet known exactly what neural mechanisms control odor and taste in the fly brain.
A specialized receptor called DTKR is responsible for regulating the activity of the olfactory system. When flies are starved, their insulin levels decrease and two neuropeptide signaling systems are activated. The short neuropeptide F helps transmit signals from DM1 to DM5 glomeruli, whereas the long neuropeptide F inhibits the transmission of signals in DM5. These two systems help flies pursue less optimal food sources during times of scarcity.
