Odor Receptor Helps Mosquitoes Target People
Date: 15-Jan-04
Country: USA
Author: Merritt McKinney
The identification of this smell receptor raises the possibility of developing better insect repellents or mosquito traps, the study's lead author told Reuters Health.
"We found that a particular mosquito smell receptor is exquisitely sensitive to a human sweat odor," said Dr. John R. Carlson of Yale University in New Haven, Connecticut. This receptor, he explained, may help mosquitoes locate their next meal.
"This finding could be used in designing new insect repellents or in identifying strong attractants for use in insect traps," Carlson said. The next step, according to the Yale researcher, will be to find other chemicals that block this receptor or activate it strongly.
The prospect of a better bug repellent may sound like a good idea to fans of backyard barbecues everywhere, but mosquitoes are more than a minor irritation in many parts of the world. Malaria-carrying Anopheles mosquitoes are to blame for more than one million deaths per year.
Carlson and his colleagues developed a method of identifying odors that activate mosquito smell receptors. Through a little genetic tinkering, the researchers caused fruit fly neurons on the insects' antennae to produce mosquito smell receptors.
These altered bugs did not respond to most odors, because the fruit flies normal smell receptors had been removed. But a mosquito smell receptor called AgOr1 had a strong response to a component of human sweat, the researchers report in Thursday's issue of the journal Nature.
Carlson and his team suspect that AgOr1 may help mosquitoes home in on their human targets, because this receptor is expressed only in female mosquitoes, which need blood for producing offspring. Levels of the receptor diminish after a female mosquito has had a meal of blood.
Carlson told Reuters Health that he and his colleagues are continuing to examine other mosquito odor receptors to see what triggers them. Although the current research involved mosquitoes, he noted that "the method could also be used to design new ways of controlling other insect pests."