A MULTIGENE FAMILY ENCODING A DIVERSE ARRAY OF PUTATIVE PHEROMONE RECEPTORS IN MAMMALS

The vomeronasal organ of mammals is an olfactory sensory structure tha t detects pheromones. It contains two subsets of sensory neurons that differentially express G alpha(o) and G alpha(i2). By comparing gene e xpression in single neurons, we identified a novel multigene family th at codes for a diverse array of candidate pheromone receptors (VRs) ex pressed by the G alpha(o)(+) subset. Different VRs are expressed by di fferent neurons, but those neurons are interspersed, suggesting a dist ributed mode of sensory coding. Chromosome mapping experiments suggest an evolutionary connection between genes encoding VRs and receptors f or volatile odorants. However, a dramatically different structure for VRs and the existence of variant VR mRNA forms indicate that there are diverse strategies to detect functionally distinct sensory stimuli.