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(A-D) Immunofluorescent images of p-S6 staining on transverse cryosections from MTZ⁺ DMSO-, rapamycin- or INK128-treated larvae at 2dpi. Nuclei (white), p-S6 (magenta) (E) p-S6 levels in the RPE layer were significantly decreased in rapamycin-treated and INK128-treated larvae when compared with DMSO-treated controls. (F) Schematic of the experimental paradigm showing the timeline for chemical treatments and ablation. (G-J) Immunofluorescent images of BrdU staining on transverse cryosections from MTZ^- DMSO-, rapamycin- and INK128-treated larvae at 9dpf and (L-O) from MTZ⁺ DMSO-, rapamycin- or INK128 -treated larvae at 4dpi. White arrowheads indicate BrdU⁺ cells in the RPE layer. Nuclei (white), BrdU (magenta). (K) Quantification of BrdU⁺ cells in the MTZ^- RPE layer showed no significant differences between DMSO-treated and inhibitor-treated larvae. (P) Quantification of BrdU⁺ cells in the RPE layer showed significantly fewer BrdU+ cells in MTZ⁺ rapamycin- and INK128-treated larvae when compared to DMSO-treated controls. (Q-T) Brightfield images of cryosections from MTZ⁺ DMSO-, rapamycin- or INK128-treated larvae at 4dpi. White arrows indicate the edges of pigment recovery. (U) Quantification of percent RPE recovery showed a significant impairment in pigment recovery in rapamycin- or INK128-treated larvae. p-values: ** ≤ 0.01, ***≤ 0.001, and **** ≤ 0.0001. Statistical information can be found in S9 Table. Dorsal is up and distal is left. Scale bar = 50μm.