By 3.5 days post-infection with the GFAP-Math5-Brn3b-tdTomato AAVs, no tdTomato+ axons were seen in the optic nerve (Supplementary Figure 5F), in agreement with the observation that there were no RGCs reprogrammed from MG by this time (Figure 1E). This evidence concerns the gene POU4F2 and infection.