A CRISPR screen identifies a pathway required for paraquat-induced cell death

A positive-selection CRISPR screen with the pro-oxidant paraquat (PQ) uncovers three genes mediating PQ-induced cell death: POR is the source of PQ-mediated reactive oxygen species (ROS) generation, and ATP7A and SLC45A4 promote oxidant-dependent cell death. Paraquat, a herbicide linked to Parkinson's disease, generates reactive oxygen species (ROS), which causes cell death. Because the source of paraquat-induced ROS production remains unknown, we conducted a CRISPR-based positive-selection screen to identify metabolic genes essential for paraquat-induced cell death. Our screen uncovered three genes, POR (cytochrome P450 oxidoreductase), ATP7A (copper transporter), and SLC45A4 (sucrose transporter), required for paraquat–induced cell death. Furthermore, our results revealed POR as the source of paraquat-induced ROS production. Thus, our study highlights the use of functional genomic screens for uncovering redox biology.