Submitted to: Journal of Visualized Experiments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/20/2014
Publication Date: 12/30/2014
Citation: Sparks, J.T., Dickens, J.C. 2014. Physiological recordings and RNA sequencing of the gustatory appendages of the yellow-fever mosquito Aedes aegypti. Journal of Visualized Experiments. p.94 DOI:10.3791/52088.
Interpretive Summary: Chemical repellents decrease interactions between mosquitoes and their human hosts, and thus are important tools for protection of humans from diseases such as malaria, dengue fever and West Nile virus. Here we demonstrate electrophysiological techniques used by us to discover the first taste receptor for repellents in the yellow fever mosquito. We then show methods used to isolate tissues containing the taste receptors and approaches that were implemented to characterize candidate genes responsible for the activity elicited by the repellents. Our detailed approach may be used by entomologists and molecular biologists to discover new behavioral chemicals and determine the genes involved in their detection by mosquitoes and other insects. This new knowledge may lead to the discovery of novel repellents for protection of humans and animals from disease vectors
Technical Abstract: Electrophysiological recording of action potentials from sensory neurons of mosquitoes provides investigators a glimpse into the chemical perception of these disease vectors. We have recently identified a bitter sensing neuron in the labellum of female Aedes aegypti that responds to DEET and other repellents, as well as bitter quinine through direct electrophysiological investigation. These gustatory receptor neuron responses prompted our sequencing of total mRNA from both male and female labella and tarsi samples to elucidate the putative chemoreception genes expressed in these contact chemoreception tissues. Tarsi samples were divided into pro-, meso- and metathoracic subtypes for both sexes. We then validated our dataset by conducting qRT-PCR on the same tissue samples and used statistical methods to compare results between the two methods. Studies addressing molecular function may now target specific genes to determine those involved in repellent perception by mosquitoes. These receptor pathways may be used to screen novel repellents towards disruption of host-seeking behavior to curb the spread of harmful viruses.