To find factors other than HRD1 that limit retinal degeneration in adRP, we performed a gain-of-function screen using a Drosophila model in which Rh1G69D was ectopically overexpressed using the GMR-Gal4 system (GMR>Rh1G69D) (Fig 1A–1D and S1A–S1B Fig). Here, LGALS4 is linked to retinal degeneration.