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Castillo, J. S.

Publications and source records attributed to Castillo, J. S..

2 recordsLinked to original sources

Odor and bacterial signatures for humans that attract different mosquito species

Humans are not equally attractive to mosquitoes, leaving some more vulnerable to mosquito-borne illnesses than others. Body odor differences likely allow mosquitoes to discriminate between humans. Using a uniport olfactometer, we measured the attraction of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus mosquitoes for each of our 119 participants. Ae. aegypti, but not other species tested, were more attracted to male than female participants. Each of our three species ranked our participants differently, favoring a distinct subset of our cohort. For each species, mosquito attraction rates were used to define high and low attraction human odors and bacterial taxa. For example, Ae. aegypti and Cx. quinquefasciatus attraction was associated with the absence of odors like cyclic alcohols and monoterpenes, while Ae. albopictus attraction was associated with the presence of ketones. Each mosquito species exhibited distinct responses to individual humans, emphasizing both unique and shared cues for targeting their hosts.

neuroscience↗

Carboxylic acids that drive mosquito attraction to humans activate ionotropic receptors

The mosquito, Aedes aegypti, is highly anthropophilic and continues to transmit debilitating arboviruses within human populations. Female mosquitoes are attracted to sources of blood by responding to odor plumes that are emitted by their preferred hosts. Acidic volatile compounds, including carboxylic acids, represent particularly salient odors driving this attraction. Importantly, carboxylic acids are major constituents of human sweat and volatiles generated by skin microbes. As such, they are likely to impact human host preference, which is a dominant factor in disease transmission cycles. A more complete understanding of mosquito host attraction will necessitate the elucidation of molecular mechanisms of volatile odor detection that function in peripheral sensory neurons. Recent studies have shown that members of the variant ionotropic glutamate receptor gene family are necessary for physiological and behavioral responses to acidic volatiles in Aedes. In this study, we have identified a subfamily of variant ionotropic receptors that share sequence homology across several important vector species and are likely to be activated by carboxylic acids. Moreover, we demonstrate that selected members of this subfamily are activated by short chain carboxylic acids in a heterologous cell expression system. Our results are consistent with the hypothesis that members of this receptor class underlie acidic volatile sensitivity in vector mosquitoes and provide a frame of reference for future development of novel mosquito attractant and repellent technologies.

molecular biology↗