Predatory animals pursue prey in a noisy sensory landscape, deciding when to continue or abandon their chase. The mosquito Aedes aegypti is a micropredator that first detects humans at a distance through sensory cues such as carbon dioxide. As a mosquito nears its target it senses more proximal cues such as body heat that guide it to a meal of blood. How long the search for blood continues after initial detection of a human is not known. Here we show that a 5-second optogenetic pulse of fictive carbon dioxide induced a persistent behavioral state in female mosquitoes that lasted for more than 10 minutes. This state is highly specific to females searching for a blood meal and was not induced in recently blood-fed females or in males, who do not feed on blood. In males that lack the gene fruitless, which controls persistent social behaviors in other insects, fictive carbon dioxide induced a long-lasting behavior response resembling the predatory state of females. Finally, we show that the persistent state triggered by detection of fictive carbon dioxide enabled females to engorge on a blood meal mimic offered up to 14 minutes after the initial 5-second stimulus. Our results demonstrate that a persistent internal state allows female mosquitoes to integrate multiple human sensory cues over long timescales, an ability that is key to their success as an apex micropredator of humans.
Data availabilityAll data generated or analyzed during this study are included in the manuscript and Source Data Files 1-4. Large datasets are available at https://github.com/trevorsorrells/Optothermocycler.Code availabilityAnalysis code used in this publication is available at https://github.com/trevorsorrells/Optothermocycler.
- Trevor R Sorrells
- Leslie B Vosshall
- Trevor R Sorrells
- Trevor R Sorrells
- Trevor R Sorrells
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: Blood feeding of mosquitoes with live anesthetized mice was conducted according to approved institutional animal care and use committee (IACUC) protocol #17108 of The Rockefeller University.
Human subjects: Blood feeding of mosquitoes with human volunteers was conducted according to IRB protocol LV-0652. Human volunteers gave written informed consent to participate in the experiments.
- Sonia Sen, Tata Institute for Genetics and Society, India
- Received: December 29, 2021
- Accepted: May 11, 2022
- Accepted Manuscript published: May 12, 2022 (version 1)
© 2022, Sorrells et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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