The ion channel ppk301 controls freshwater egg-laying in the mosquito Aedes aegypti
Abstract
Female Aedes aegypti mosquitoes are deadly vectors of arboviral pathogens and breed in containers of freshwater associated with human habitation. Because high salinity is lethal to offspring, correctly evaluating water purity is a crucial parenting decision. We found that the DEG/ENaC channel ppk301 and sensory neurons expressing ppk301 control egg-laying initiation and choice in Ae. aegypti. Using calcium imaging, we found that ppk301-expressing cells show ppk301-dependent responses to water but, unexpectedly, also respond to salt in a ppk301-independent fashion. This suggests that ppk301 is instructive for egg-laying at low salt concentrations, but that a ppk301-independent pathway is responsible for inhibiting egg-laying at high salt concentrations. Water is a key resource for insect survival and understanding how mosquitoes interact with water to control different behaviors is an opportunity to study the evolution of chemosensory systems.
Data availability
Source data for all plots in Figures 1-3 and Figure 5-7 are provided in Supplementary File 1.
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The neurotranscriptome of the Aedes aegypti mosquito.NCBI BioProject, PRJNA236239.
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| Improved reference genome of Aedes aegypti informs arbovirus vector control.NCBI Assembly, GCF_002204515.2.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Benjamin J Matthews
- Leslie B Vosshall
Jane Coffin Childs Memorial Fund for Medical Research
- Benjamin J Matthews
- Meg A Younger
Grass Foundation
- Meg A Younger
Leon Levy Foundation
- Meg A Younger
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: For routine strain maintenance, animals were blood-fed on live mice or human subjects. Adult females of all genotypes were blood-fed on a single human subject during mutant generation, for behavioral assays, and calcium imaging. Blood-feeding procedures with live hosts were approved and monitored by The Rockefeller University Institutional Animal Care and Use Committee (IACUC protocol 15772) and Institutional Review Board, (IRB protocol LV-0652). Human subjects gave their written informed consent to participate.
Human subjects: For routine strain maintenance, animals were blood-fed on live mice or human subjects. Adult females of all genotypes were blood-fed on a single human subject during mutant generation, for behavioral assays, and calcium imaging. Blood-feeding procedures with live hosts were approved and monitored by The Rockefeller University Institutional Animal Care and Use Committee (IACUC protocol 15772) and Institutional Review Board, (IRB protocol LV-0652). Human subjects gave their written informed consent to participate.
Reviewing Editor
- Kristin Scott, University of California, Berkeley, United States
Version history
- Received: November 28, 2018
- Accepted: May 20, 2019
- Accepted Manuscript published: May 21, 2019 (version 1)
- Version of Record published: June 27, 2019 (version 2)
Copyright
© 2019, Matthews 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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