Sense of Smell Wins Nobel Prize (cont.)
Each olfactory receptor cell possesses only one type of odorant receptor, and each receptor can detect a limited number of odorant substances. Our olfactory receptor cells are therefore highly specialized for a few odors.
From these microdomains in the olfactory bulb, the information is relayed further to other parts of the brain, where the information from several olfactory receptors is combined, forming a pattern.
Lilacs and Strawberries
When something tastes really good it is primarily activation of the olfactory system which helps us detect the qualities we regard as positive. A good wine or a sunripe wild strawberry activates a whole array of odorant receptors, helping us to perceive the different odorant molecules.
Loss of Sense of Smell
To lose the sense of smell is a serious handicap -- we no longer perceive the different qualities of food and we cannot detect warning signals, for example smoke from a fire.
The following sections provide more information about the science of our system of smell and are based upon the press release today from the Nobel Assembly.
Deciphering a Sensory
Each odorant receptor first activates a G protein, to which it is coupled. The G protein in turn stimulates the formation of cAMP (cyclic AMP). This messenger molecule activates ion channels, which are opened and the cell is activated. Axel and Buck showed that the large family of odorant receptors belongs to the G protein-coupled receptors (GPCR).