From chemoreception to control : the functional characterization of insect odorant receptors and exploration of novel toxins for improved arthropod management.

Insects wield considerable influence over our world, constituting half of all Eukaryotic species and playing indispensable roles in nearly every ecosystem. Their impact on human life and well-being is immense. While most insects are benign or even beneficial, some species pose significant threats to human health by spreading diseases and jeopardizing human flourishing through the destruction of agricultural products. Despite the availability of numerous control measures, the challenges of climate change and the emergence of insecticide resistance raise concerns about the effectiveness of these methods. Additionally, many compounds used for insect control and disease prevention are hazardous to human health. To address these challenges, we embarked on a study of alternatives certified as Generally Regarded As Safe (GRAS) for human use and consumption to identify toxins for disease-vectoring mosquitoes. Insects rely heavily on olfaction for behaviors such as host-seeking, mate selection, nectar foraging, and oviposition. Olfaction's molecular mechanism centers on ligand-gated ion channels known as odorant receptors, expressed on olfactory neurons. These receptors, in collaboration with coreceptors, selectively bind environmental ligands, initiating neuronal responses. Our research focused on odorant receptors associated with lesser-studied behaviors: nectar foraging in the vector mosquito Aedes aegypti and oviposition in the agriculturally significant Tortricidae family of moths. These behaviors are crucial for the survival of the species, though the olfactory components behind them remain unelucidated. Through these investigations, we identified ligands corresponding to these receptors, uncovered numerous potentially behaviorally relevant ligands, and contributed to an enhanced understanding of insect olfaction. Our ultimate goal is to merge insecticide alternatives with compounds activating odorant receptors to create novel mechanisms for insect surveillance and control.