Fig. 2. Neurod1 and Math3 partially restore the optic nerve in Math5-null mice. (A) Dissected eyes from P30 mice. From left to right: Math5^lacZ-KI/+, Math5^{Neurod1-KI/lacZ-KI} and Math5^{lacZ-KI/lacZ-KI}. (A1,A2) Cross-sections of the optic nerves from Math5^lacZ-KI/+ and Math5^{Neurod1-KI/lacZ-KI} dissected eyes shown in A were stained with Cresyl Fast Violet. (B) Histological sections of P30 eyes from wild-type and Math5^{Neurod1-KI/Math3-KI} littermates. Arrowheads indicate the optic nerves. The double arrowhead indicates a rosette structure sometimes seen in Math5^{Neurod1-KI/Math3-KI} retinas (inset). (B1,B2) Pou4f2 expression in wild-type and Math5^{Neurod1-KI/Math3-KI} retinal sections. Representative lateral regions were used for comparison. ONL, outer nuclear layer; INL, inner nuclear layer; GCL, ganglion cell layer. Scale bars: 50 µm in A1; 200 µm in B.