TBL1X and retinal degeneration: We thus considered light exposure as a potential trigger for age-related retinal degeneration mediated by ebi. Flies with ebi mutant retinae that were cultured under constant illumination showed severe degeneration by 14 days after eclosion (Figure 7A–E, compare with Figure 1C), whereas wild-type ommatidia did not show any structural changes under the same conditions (Figure 7A).