Figure 2 : Light-induced photoreceptor damage in retinas of Sema4AF350C/F350C mice.

From: A point mutation in Semaphorin 4A associates with defective endosomal sorting and causes retinal degeneration

Figure 2

(a) Hematoxylin and eosin (HE) staining of retinas in 4-week-old wild-type (Sema4A+/+), Sema4AWT/WT, Sema4AD345H/D345H, Sema4AF350C/F350C, Sema4AR713Q/R713Q, Sema4AD345H/F350C and Sema4A-deficient (Sema4A−/−) mice. Among them, Sema4AF350C/F350C and Sema4A−/− retinas showed loss of the outer nuclear layer. Scale bar, 50 μm. RPE, retinal pigment epithelium; ONL, outer nuclear layer; INL, inner nuclear layer; RGL, retinal ganglion layer. (b) ERG responses to single flashes were recorded using wild-type (Sema4A+/+), Sema4AF350C/F350C and Sema4A−/− mice in a scotopic condition at 2 or 4 weeks of age. Virtually no ERG responses were detected in Sema4A−/− and Sema4AF350C/F350C retinas as early as 2 weeks of age. (c) Representative images from the TUNEL assay using P10 mouse retinas after 0, 60 and 120 min of light exposure. Scale bar, 50 μm. (d) Histogram showing the average number of TUNEL-positive cells (±s.e.m.; n=5–10) in retinas. *P<0.01 (Student’s t-test). Photoreceptor apoptosis peaked in Sema4A−/− and Sema4AF350C/F350C retinas after 60 min of exposure. Data are representative of three independent experiments.