Odors are detected by a specialized set of cells called olfactory sensory neurons (OSNs). There are different subtypes of OSNs, which are identified by the olfactory receptor gene (Olfr) they express and detect specific subsets of odourants. OSN subtypes are organized in stereotypic anatomic locations of the olfactory epithelium called "zones". A comprehensive and quantitative mapping of the zones, as well as an understanding of their function, is still missing.
During this talk, I will present the analysis of a spatial transcriptomic dataset that allowed us to build the first transcriptome-wide tridimensional map of the olfactory mucosa (OM). Topographic maps of genes differentially expressed in space reveal that both Olfrs and non-Olfrs genes are distributed in a continuous and overlapping fashion over five broad zones in the OM.
Using machine learning methods, we have quantitatively identified the "zones" and characterized their transcriptional signature. Finally, I will show how the distribution of Olfrs inside the zones suggests they might be optimized to enhance odor discrimination.