Identification of Suppressor Genes in the Yeast Model of Cystinosis

Cystinosis is a pediatric lysosomal storage disorder caused by loss-of-function mutations in the CTNS gene, which encodes the cystine effluxer Cystinosin. A significant side-effect observed in cystinotic patients is multi-systemic cell death, and the mechanism behind this effect is largely unknown. We have selected Saccharomyces cerevisiae, a model organism for higher eukaryotes, to explore the consequences stemming from the loss of Cystinosin. Yeast is responsive to genetic manipulation and has a genome that is fully sequenced and highly annotated. After confirming that the yeast protein Ers1p is a suitable ortholog of human Cystinosin, we aimed to better understand the role Ers1p plays in yeast by identifying genes that interact with ERS1. We will investigate sixteen genes that, as identified via a functional genomic screen, exhibit increased or decreased expression in the absence of ERS1. Our findings will contribute to our understanding of cystinosis, and also to fundamental pathways in yeast and othe...