Deaf male mosquitoes don't mate, researchers discover

Romance is a complex affair in humans. There's personality, appearance, seduction, all manner of physical and social cues. Mosquitoes are much more blunt. Mating occurs for a few seconds in midair. And all it takes to woo ...

Now a study by UC Santa Barbara reveals that this is really all there is to it. Researchers in Professor Craig Montell's lab created deaf mosquitoes and found that the males had absolutely no interest in mating. "You could leave them together with the females for days, and they will not mate," Montell said. The dramatic change was simple to produce. "The absence of a single gene, trpVa, produced this profound effect on mosquito mating behavior," explained co-lead author Dhananjay Thakur, a postdoctoral scholar in the Department of Molecular, Cellular, and Developmental Biology.

The results, published in the Proceedings of the National Academy of Sciences could have major implications for how we manage disease transmission by better controlling the populations of mosquito vectors, such as Aedes aegypti, that infect hundreds of millions of people every year with viruses that cause diseases. Frisky skeeters "On summer evenings, we often see swarms of mosquitoes gathered by the water or under streetlights. These gatherings are essentially mass mating events," said co-lead author Yijin Wang, a former postdoc at UCSB. Although mosquitoes possess an extraordinary ability to reproduce, scientists still have a limited understanding of the molecular and neurological mechanisms at work.

If a male mosquito can't hear a female. It's as though she doesn't exist. Credit: Matt Perko Read more

For male mosquitoes, it’s love at first sound, not first sight. Credit: Dhananjay Thakur Read more

trpVa is expressed in the JO with sexually dimorphic axonal projections. (A) Cartoon of a male head. (B and C) Expression of the trpVa reporter (trpVaQF2>QUAS-mCD8-GFP) in a cross-section of a JO from a male. The mCD8-GFP (trpVa reporter) was detected using anti-mCD8 (green) and F-actin was labeled using a fluorescently labeled phalloidin (magenta). Regions with type A–D scolopidia are indicated. (D–F) Axonal projections labeled with the trpVa reporter in a male brain. Anti-nc82 (magenta) broadly labels neuropils throughout the brain (40). (G) Cartoon of a female head. (H and I) Expression of the trpVa reporter in a cross-section of a JO from a female. (J–L) Axonal projections labeled with the trpVa reporter in a female brain. Credit: Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2404324121 Read more