Sensory organs allow animals to extract information from their surroundings, and to build a representation of the outside world. A good representation of the environment is a prerequisite for an organism to respond to its peers, predators or prey, for example. To do this, various organisms rely heavily on their sense of smell. Indeed, olfaction is the most important sense for many animals, including mice.The mouse olfactory organ is composed of neurons, which each express a single type of chemosensory receptor. These receptors are involved in detecting odorants or pheromones and are the foundation block of olfaction. Until now, five major families of olfactory chemoreceptors have been identified, all of which are G-protein coupled receptors. Recently, the Rodriguez lab has identified a novel population of neurons in the main olfactory epithelium (MOE) defined by their expression of TrpC2, a protein usually absent in this area. Preliminary evidence suggests that these few thousand neurons do not express any of the five types of known olfactory chemoreceptors and are thus likely to contain an undefined receptor family. Here, we plan to use a novel approach to identify these receptors. We will use fluorescence-activated cell sorting to specifically isolate the population of interest from transgenic mice engineered so that the TrpC2-expressing neurons are fluorescently labeled. We will then perform deep-sequencing of these neurons’ transcriptome to identify candidate chemoreceptors, and will further characterize these candidates using RT-PCR and in situ hybridization.In addition, in a separate approach we will generate a knock-in line allowing us to conditionally silence the TrpC2 neurons in the MOE. Using various standard assays, we will test the behavioral role of this neuronal population.By potentially identifying a new chemoreceptor family and assessing its behavioral function, this work will greatly contribute to our better understanding of olfaction.