MADISON -- Fruit flies don't have noses, but a huge part of their brains is dedicated to processing smells. Flies probably rely on the sense of smell more than any other sense for essential activities such as finding mates and avoiding danger.
UW-Madison researchers have discovered that a gene called distal-less is critical to the fly's ability to receive, process and respond to smells.
As reported in the current issue of the Proceedings of the National Academy of Sciences, the scientists also found evidence that distal-less is important for generating and maintaining self-renewing stem cells in the large brain structure that's responsible for processing odors and carrying out other important duties.
The corresponding gene in mammals and humans, called Dlx, is known to be important in the sense of smell. The Dlx gene has also been implicated in autism and epilepsy. By studying how distal-less works in fruit fly neurons, the scientists also hope to expand understanding of Dlx.
"We're really interested in knowing at a very fundamental level what distal-less is doing in the fly olfactory system and how it's doing it," says senior author Dr. Grace Boekhoff-Falk, associate professor of cell and regenerative biology at the School of Medicine and Public Health. "We're also hoping that what we learn in flies can give us a better understanding of how Dlx works in vertebrates, including humans."
Studying distal-less is much easier than studying Dlx, she adds, partly because mice and humans have six Dlx genes while flies have only one distal-less.
Odors enter fruit flies through nerve cells designed to receive smells--olfactory receptor neurons. From receptor neurons, projection neurons relay olfactory information to the large brain structure called the mushroom body (MB), which then triggers the animals to move in the right directiontowards the fragrance of food, for example, or away from the od
|Contact: Dian Land|
University of Wisconsin-Madison