α7/β-gal is not expressed by mature olfactory receptor neurons.

<p>A-C: The <i>α7</i>^{<i>lacZ/lacZ</i>} olfactory bulb expresses α7/β-gal (green) in the olfactory nerve layer (ONL), and is closely associated with the olfactory marker protein (OMP, red). In axons of mature olfactory receptor neurons, OMP immunoreactivity fills their synaptic target, the glomeruli (G). α7/β-gal expression and OECs are excluded from the glomeruli. D-F: Fascicles of the olfactory nerve within the lamina propria (LP) have distinct areas of β-gal (green, arrows) and OMP-positive (red) immunoreactivity. β-gal-labeled OECs surround the OMP-labeled axon bundles. The olfactory epithelium (OE) contains OMP-labeled (red) olfactory receptor neurons. Scale bars for A-C: 50 μm; D-F: 20 μm.