Silencing the Buzz How Tuning into Mosquito Love Songs Can Help Fight Malaria

Scientists have explored the hearing of Anopheles mosquitoes and its impact on their mating behavior. Published in Nature Communications, the study found that the neurotransmitter octopamine is vital for mosquito hearing and consequently their reproduction.

Biologist Prof. Dr. Jörg Albert from the University of Oldenburg, together with researchers from University College London (UK), has studied the sense of hearing of tropical mosquitoes of the genus Anopheles and the importance of the sense of hearing for mating behavior. The findings could offer a new approach to combat the malaria-carrying insects. The results have now been published in the prestigious journal Nature Communications.

The researchers found that the neurotransmitter octopamine plays a crucial role in hearing and thus indirectly in the reproduction of mosquitoes. If the animals come together at dusk to form large, short-lived swarms, then males recognize the females among hundreds of animals by their deeper flight tone. It has now been demonstrated that certain octopamine receptors in the ear play a special role in this situation.

Increased octopamine activity at swarming time causes the male mosquito to “prick up its ears.” Fine hairs are erected on the antennae that catch the sound, which can capture the sound more effectively. In addition, the entire antenna stiffens, which further alters acoustic sensitivity. All of this, they hypothesize, causes the males to hear the females better. The researchers were able to demonstrate that these responses are weaker or completely absent when the mosquitoes are exposed to a weakly toxic insecticide, the pesticide amitraz. This substance, normally used against ticks and parasitic mites, turns off the mosquitoes' octopamine receptor. If males subsequently can't spot females in the swarm, that's a possible way to curb reproduction of this mosquito species and reduce its population, the researchers said.

“Mosquito hearing is a process of remarkable complexity. With our findings on the role of the neurotransmitter octopamine, we are just scratching the tip of a gigantic iceberg,” Albert says. “I'm sure future research will not only let us better understand mosquitoes' sense of hearing, but also help us fight mosquito-borne diseases like malaria and dengue fever.”

The biologist and biophysicist has been conducting research at the University of Oldenburg since the beginning of the year. Previously, he worked at UCL, with which he will continue to collaborate closely.

(ID:49645077)