PurA sensitizes cells to toxicity induced by oxidative stress

Abstract Objectives PurA is an evolutionary conserved protein that is known to bind to single stranded DNA or RNA and regulate both transcription and translation. PurA has been implicated in many neurological and neurodevelopmental deficits, but its role in response to cellular stress has not yet been clarified. In this study, we have studied the cells’ stress response in the presence and absence of PurA expression. Methods Oxidative stress was induced in MEF cells obtained from PURA WT and K/O mice by paraquat treatments. The cellular response to stress was determined and compared by viability assays, immunocytochemistry and biochemical analyses. Results Interestingly, paraquat treated PurA expressing MEF cells showed higher sensitivity and less cellular viability than those with no PurA expression. Moreover, western blot analysis revealed increase in the expression of the apoptotic marker cleaved caspase 3 and autophagy marker LC3-II in PurA WT MEF cells compared to the PurA K/O MEF cells under oxidative stress induction. Conclusions Our observations indicate that PurA may play a key role in regulating cellular toxicity induced by oxidative stress and emphasize its importance for cell-fate determination under cytotoxic stress conditions.