POU4F2 and infection: Robust number of GFP+ RGCs appeared only when GFAP-Math5-Brn3b-GFP AAVs were used for infection; (3) By 3.5 days post-infection of retinas with GFAP-Math5-Brn3b-GFP AAVs, many MG but no RGCs were GFP+; only after 5.5 days post-infection were GFP+ RGCs seen, consistent with the time-window of RGC reprogramming and the appearance of intermediate cells (Figures 1, 4).