Senior Research Fellow
Ph.D. University of Neuchâtel, Switzerland
The chemical senses are crucial to the survival of most insects. How are olfactory and gustatory systems adapted to the chemical environment that a particular species finds itself in? How do chemical stimuli drive resource-oriented behaviors? Answering these questions will help us understand how pest insects find us and our crops as well as provide insight into fundamental coding properties of our own brain.
Odors are detected by olfactory receptor neurons (ORNs). Large numbers of these neurons occur in our nose and in the antennae of insects. They are organized in response classes, each tuned to a different range of chemicals. Odors are thus encoded across an array of detectors, often with overlapping sensitivities. Because it has a relatively small number of these coding units, Drosophila has become a favorite model for studying the neurobiology and development of the olfactory system.
The response properties of ORNs can be studied with electrophysiological methods. Molecular and genetic methods can be used to target cells or proteins of the olfactory system. A family of 60 receptor genes has provided a molecular explanation for the response properties of different neuronal classes. How do tuning properties of the neurons relate to the expression of members of the receptor gene family? How are innate behavioral responses driven by this system of genes and ORN classes?
The combination of detailed physiological analysis and powerful genetic techniques allows us to study the cellular mechanisms of odor detection as well as compare odor coding across species. For instance, carbon dioxide is a chemical stimulus that perceived by a single neuron class in many insect species. In Drosophila we can manipulate these neurons genetically.