Whether you opt for repellent, long sleeves or citronella coils, the dreaded drone of a mosquito always seems to find its way back to you.
Now researchers say they’ve found the mechanism behind the insect’s ability to interact with humans.
Humans release a fragrant cocktail of body odor, heat, and carbon dioxide, which varies from person to person, and mosquitoes use to find their next meal. While most animals have a specific set of neurons that detect each type of odor, mosquitoes can pick up odors in different ways, suggests the study, published in the scientific journal Cell.
“We found that there is a real difference in the way mosquitoes encode the odors they encounter compared to what we’ve learned from other animals,” said Meg Younger, an assistant professor of biology at Boston University and one of the lead authors. of the study.
Researchers at Rockefeller University in New York were stunned when mosquitoes could somehow still find humans to bite after deleting an entire family of human odor-sensitive proteins from their genome.
The team then examined odor receptors in mosquitoes’ antennae, which bind to chemicals floating around in the environment and send a signal to the brain via neurons.
“We assumed that mosquitoes would follow the central dogma of smell, which is that only one type of receptor is expressed in each neuron,” Younger said. “Instead, we’ve seen that different receptors can respond to different smells in the same neuron.”
This means that losing one or more receptors will not affect mosquitoes’ ability to pick up human odors. This backup system could have evolved as a survival mechanism, the researchers say.
“The mosquito Aedes aegyptian specializes in biting humans, and they are believed to have evolved to do that because humans are always near fresh water and mosquitoes lay their eggs in fresh water. We’re basically the perfect meal, so the urge to find people is extremely strong,” says Younger.
Ultimately, the researchers say, understanding how the mosquito brain processes human scent could be used to intervene in biting behavior and reduce the spread of mosquito-borne diseases, such as malaria, dengue and yellow fever.
“A key strategy for controlling mosquitoes is to lure them into traps to remove them from the biting population. If we could use this knowledge to understand how human scent is displayed in the antennae and brains of mosquitoes, we would “We could also develop mixtures that are more attractive to mosquitoes than we are. We could also develop repellents that target those receptors and neurons that detect human scent,” Younger said.
dr. Olena Riabinina, of the Insect Neuro Lab at Durham University, who was not involved in the study, said: “We already knew that mosquitoes are determined to bite humans, but this research tells us that their olfactory system is different and more complicated. than we thought, interventions based on this new information could be promising.”
dr. Marta Andres Miguel, from University College London, who was also not involved, said: “This is a remarkable discovery, not only from a basic biology perspective, but also from a disease control perspective, as it opens up new avenues for the development of new tools to control mosquitoes. to fight them, either to lure them into traps or to repel them and avoid human biting.”
#Scientists #discover #mosquitoes #sniff #people