Fig. 1.

RTBDN is critical for energy homeostasis and cellular redox potential of NR and RPE-Ch. Essential flavins like (A) FAD and (B) FMN and metabolite ratios of (C) ATP/ADP, (D) ATP/AMP, (E) NAD⁺/NADH, and (F) NADP⁺/NADPH, which are critical to evaluate the state of cellular homeostasis, were quantified in the neural retina NR and RPE-Ch of Rtbdn^−/− and WT controls at P45 and P120. Values for Rtbdn^−/− are presented as percent of age-matched WT (red dotted line is set at 100). Statistical comparisons were made between the WT and Rtbdn^−/− for the individual metabolite of each tissue and at the respective ages. Tissues were collected as indicated in the Materials and Methods section, with n = 10 for A and B and n = 6 for C–F. Student’s t test was used to determine significance, with **P < 0.01, ***P < 0.001, and ****P < 0.0001. (NR, neural retina; RPE-Ch, RPE–Choroid).