Research Uncovers Details of How Sense of Smell Works; First Aroma Scientists Detect Is That of Meat
Molecular biologists at Columbia University for the first time have linked a particular odor with the proteins in the human nose that detect it. They made their first match with the smell of meat.
The research, by a team of biologists led by Stuart Firestein, associate professor of biological sciences at Columbia, is reported in the Jan. 9 issue of the journal Science. It builds on work conducted at Columbia that discovered the receptors' proteins that stick out from nerve cells in the nasal cavity and connect to molecules floating in the air, setting in motion a cascade of reactions that create a perception of odor in the brain.
"I believe this experiment will prove to be a Rosetta stone for olfaction, in that we can now begin to match odorants to receptors and decode this elusive sense," said Darcy Kelley, professor of biological sciences at Columbia, in an interview.
Researchers sprayed 74 individual scents, one at a time, over rat nerve cells that contained a particular odor receptor they had inserted in the cells. The first odor they matched to a receptor was that of octanal, which to humans smells like meat.
Linda Buck, a neuroscientist at Harvard Medical School, and Richard Axel, Higgins Professor of Biochemistry and Molecular Biophysics at Columbia's College of Physicians & Surgeons, in 1991 discovered both the family of transmembrane proteins that they believed to be odor receptors and some of the genes that code for those proteins. They found nearly 1,000 receptors, which in the human body number second only to the receptors in the immune system. Yet researchers had been unable to pair any single receptor or group of receptors with any particular odor until Professor Firestein's team reported their results.