Fig. 2: Adult Mkk4- and Mkk7-deficient animals have fewer retinal ganglion cells resulting from postnatal dropout.

a The number of TUJ-1-positive RGCs is significantly reduced in adult Mkk4- and Mkk7-deficient retinal flat mounts. Representative flat mounts are displayed to the right of the graph. (*P ≤ 0.05). N ≥ 10 retinas per genotype. b P0 flat mounts stained with BRN3B reveal normal RGC densities in both Mkk4- and Mkk7-deficient retinas, implying RGC dropout occurs postnatally. Representative flat mounts shown to the right of the graph. N ≥ 4 retinas per genotype. All examined Mkk7-deficient adult retinas displayed areas of abnormal fasciculation in both TUJ-1-positive RGCs (c; N ≥ 12) and tyrosine hydroxylase (TH)-positive amacrine cells (d; N ≥ 4). Scale bars: (a–c) 50 μm; (d) 100 μm. Error bars represent SEM