Making scents of olfactory neurogenesis.

Olfaction was long considered to belong more to the realm of art than to that of science. As a result, how the brain perceives, discriminates, and recognizes odorant molecules is still a mystery. Recent progress has nonetheless been made at early stages of the olfactory pathway when olfactory studies entered into the molecular era to elucidate the first contact of an odor molecule with a receptor. Our group focuses on the analysis of odor information in the olfactory bulb, the first processing relay in the mammalian brain. Using this model, we are attempting to decipher the code for odorant information. Furthermore, the olfactory bulb also provides an attractive model to investigate neuronal proliferation, differentiation, migration, and neuronal death, processes involving an interplay between genetic and epigenetic influences. Finally, our goal is to explore the possible consequences of the olfactory bulb plasticity, in olfactory performance. For these purposes, we aim to combine morphological, electrophysiological and behavioral approaches to investigate: (1) how the olfactory bulb processes odor molecule information, (2) how neural precursors differentiate into olfactory bulb interneurons, (3) how these newly-generated neurons integrate into an operational neural network, (4) what role they play in the adult olfactory bulb, and (5) how are basic olfactory functions maintained in such a sensory system subjected to continuous renewal of a large percentage of its neuronal population. These questions should provide new fuel for the molecular and cellular bases of sensory perception and shed light onto cellular bases of learning and memory.