Figure 2. The tdTomato-expressing retinal bipolar cells in the 5-HTR2a-cre mouse line are co-labeled with antibodies specific to type 4 and type 3b cone bipolar cells, and rod bipolar cells. A–C: In a retinal vertical section, the tdTomato-expressing retina (A) was immunostained for calsenilin (B). The overlay of A and B is shown in C. The double-positive bipolar cells are marked with stars. D–F: In a retinal whole mount with the focal plane at the distal portion of the inner nuclear layer (INL), the tdTomato-expressing retina (D) was immunostained for calsenilin (E). The overlay of D and E is shown in F. The majority of the tomato-expressing cells in the distal portion of the INL are calsenilin-positive. The tdTomato-expressing cells that do not show calsenilin staining are marked with arrowheads. The tdTomato-expressing retina was immunostained for PKCα in a retinal vertical section (G–I). The double-positive bipolar cells are marked with arrows in the somata and arrowheads pointing to the axon terminals. J–L: The tdTomato-expressing retina was immunostained for PKARIIβ. Two double-positive cells are marked with stars. The tdTomato-expressing retinal bipolar cells were not labeled by antibodies for HCN4 (M–O) and Syt2 (P–R). Scale bars represent 50 µm. ONL, outer nuclear layer; IPL, inner plexiform layer; GCL, ganglion cell layer.