Examples of transcripts expressed by OSNs and by other cells in the olfactory epithelium. A,A′: Fetuin β was expressed by OSNs, sustentacular cells, Bowman’s gland, and respiratory epithelial cells. B,B′: n50J, Which encodes a protein with no known function, was expressed by OSNs, Bowman’s gland, and respiratory epithelial cells. C,C′: β-2 Tubulin was expressed by OSNs, respiratory epithelial cells, and cells in nasal gland epithelium (asterisk). D,D′:CD81, a tetraspanin, was expressed by OSNs, sustentacular cells, Bowman’s gland cells, and probably other subepithelial cells. Arrows, Bowman’s glands and ducts; arrowheads, respiratory epithelium. Dashed lines mark the location of the basement membrane. Apical is to the left in all high-magnification panels. Scale bars = 20 μm in A–D; 250 μm in A′–D′.