Phenotypic assays in yeast and zebrafish reveal drugs that rescue deficiency.

Mutations in () are causally linked to the rare neurodegenerative disorders Kufor-Rakeb syndrome, hereditary spastic paraplegia and neuronal ceroid lipofuscinosis. This suggests that ATP13A2, a lysosomal cation-transporting ATPase, plays a crucial role in neuronal cells. The heterogeneity of the clinical spectrum of -associated disorders is not yet well understood and currently, these diseases remain without effective treatment. Interestingly, ATP13A2 is widely conserved among eukaryotes, and the yeast model for deficiency was the first to indicate a role in heavy metal homeostasis, which was later confirmed in human cells. In this study, we show that the deletion of (the yeast orthologue of ) in leads to growth impairment in the presence of Zn, Mn, Co and Ni, with the strongest phenotype being observed in the presence of zinc. Using the Δ mutant, we developed a high-throughput growth rescue screen based on the Zn sensitivity phenotype. Screening of two libraries of Food and Drug Administration-approved drugs identified 11 compounds that rescued growth. Subsequently, we generated a zebrafish model for deficiency and found that both partial and complete loss of function led to increased sensitivity to Mn. Based on this phenotype, we confirmed two of the drugs found in the yeast screen to also exert a rescue effect in zebrafish--acetylcysteine, a potent antioxidant, and furaltadone, a nitrofuran antibiotic. This study further supports that combining the high-throughput screening capacity of yeast with rapid drug testing in zebrafish can represent an efficient drug repurposing strategy in the context of rare inherited disorders involving conserved genes. This work also deepens the understanding of the role of ATP13A2 in heavy metal detoxification and provides a new model for investigating deficiency.