Using genetic manipulations, the team found two proteins in mice that chaperone odorant receptors to the surface of olfactory nerves in the nose. Odorant receptors are the protein switches nestled in nerve cell membranes that trigger responses to specific volatile chemicals.
The discovery of the chaperone proteins reveals the first molecular components of the olfactory machinery that promotes proper targeting of olfactory receptors to the neuronal cell surface, said Hiroaki Matsunami, Ph.D., assistant professor of molecular genetics and microbiology at Duke. By taking advantage of the newly discovered components of the olfactory machinery, the Duke researchers have already begun tests to match the nearly 1,000 different mouse odorant receptors with the very specific chemical or chemicals to which they respond.
"In a fundamental way, the manner in which odorant receptors function remains a mystery due to technical difficulties that have largely prevented the necessary experiments," Matsunami said. "The finding of these accessory proteins opens the door toward understanding the mechanisms underlying our sense of smell."
Matsunami and his colleagues reported their results in the November 24, 2004, issue of Cell. The work was supported by the National Institutes of Health and Duke University Medical Center.
Humans and other animals can detect and discriminate among thousands of volatile environmental chemicals. The sense of smell is essential for animals to dete
Contact: Kendall Morgan
Duke University Medical Center