Figure 4. Immunofluorescent image of BRN3 positive ganglion cells. A: The merged image of BRN3A (red, panel C), BRN3B (green, panel D) and counterstained with 4',6-diamidino-2-phenylindole (DAPI, blue, panel B) is shown. This double labeling reveals four distinct classes of cell types. A cluster of cells that do not label with either BRN antibody are indicated with an asterisk. Most cells expressing BRN3 are positive for both proteins (example indicated with a straight arrow), while a minority express either BRN3A alone (example indicated with a bent arrow) or BRN3B alone (example indicated with an arrowhead). Size bar=10 µm.