Figure 3

The laminar organization of the retina is perturbed in homozygous Eml1^tvrm360 eyes. (a) Retinal sections of control eyes show dense hematoxylin-stained nuclei in the outer nuclear layer (ONL) at postnatal day (P) 8 and 1 M. In contrast, in Eml1^tvrm360 mutant retinas dense hematoxylin-stained nuclei were also observed in the GCL at P8 and in the INL at P8 and 1 M. GCL, ganglion cell layer; ONL, outer nuclear layer; INL, inner nuclear layer. Scale bar: 20 µm. (b–g) Full field ERG responses recorded in Eml1^tvrm360 (n = 5) and control littermates (n = 5) at one month of age. (b) Mean scotopic traces from a representative wild-type (WT, black) and homozygous Eml1^tvrm360 littermate (tvrm360, blue) with increasing light stimulus intensities (values indicate flash illuminance in log cd s m-2). Scale bars: vertical, 500 µV; horizontal, 50 ms. Light dose response analysis showing mean ± SEM scotopic (c) b-wave and (d) a-wave amplitudes of WT (black circles) and tvrm360 (blue circles) mice. (e) Representative photopic traces from the same mice as in (b). Scale bars: vertical, 200 µV; horizontal, 50 ms. (f) Light dose response analysis showing mean ± standard error photopic b-wave amplitudes in WT (black circles) and tvrm360 (blue circles) mice. Asterisks indicate significant values (Pairwise t-test; rod b-wave P < 0.005, rod a-wave P < 0.05, cone b-wave P < 0.0005) between mutant and control. (g) Ratio of the scotopic b- and a-wave amplitudes (b:a ratio) from full field ERG recordings of Eml1^tvrm360 and control littermates at 1 M of age. The b:a ratio is higher in controls than in mutant mice at all flash intensities evaluated (mean ± SEM), suggesting a defect in secondary neuronal signaling. Data were analyzed by a pairwise t-test. *P < 0.01.