However, they have yet to perform any tests that would support this claim. Therefore, their next step was to performed in situ hybridizations to examine patterns of expression of T2Rs in sections of various taste papillae. Figure 4 shows the functional anatomy of the rodent oral cavity. Fungiform papillae on the front half of the tongue, foliate papillae farther towards the back of the tongue, circumvallate papillae at the back of the tongue, geschmackstreifen on the palate, and the epiglottis at the back of the throat. This is important because an understanding of these tissue locations is helpful in understanding the following in situ hybridizations.
Dotted lines represent the outline of the sample taste buds.
The main point of this figure is that T2Rs are expressed in subsets of taste receptor cells. I agree with the authors that their results show T2Rs being expressed in taste receptor cells. Dotted lines represent the area of sectioned taste buds. Once again, I think that the authors conclusions are supported by the data. We see that both fluorescent probes label the same location within the taste buds, and therefore must be coexpressed in the labeled cells.