Figure 4.

The number of apoptotic cells in the ONL is increased in rho ^djh503c+/− mutant retinas at early developmental stages. (A) Representative images of TUNEL stained retinas from 3 to 5 dpf. In wildtype retinas, TUNEL positive cells (magenta) were rarely seen in the ONL from 3 to 5 dpf. In contrast, TUNEL positive cells were frequently detected in rho^djh503+/− mutants at 3 and 4 dpf, but only occasionally at 5 dpf. Rod cells are labeled by YFP (green). (B) Quantification of TUNEL positive cells in the ONL. The number of TUNEL positive cells was significantly higher in rho^djh503+/−mutants than in wildtype at 3 and 4 dpf, but not 5 dpf. Mann-Whitney test p-values: **p < 0.001, *p < 0.01. Sample size (n) of each condition is provided. DAPI (blue) was used to stain nuclei. dpf, days post-fertilization; GCL, ganglion cell layer; INL, inner nuclear layer; ONL, outer nuclear layer; rho, rhodopsin; TUNEL, terminal deoxynucleotidyl transferase dUTP nick-end labeling.