Arsenic induces caspase- and mitochondria-mediated apoptosis in Saccharomyces cerevisiae

In recent years, it has been shown that yeast, a unicellular organism, undergoes apoptosis in response to various factors. Here we demonstrate that the highly effective anticancer agent arsenic induces apoptotic process in yeast cells. Reactive oxygen species (ROS) production was observed in the process. Moreover, mitochondrial membrane potential decreased after arsenic treatment. Resistance of the rho(0) mutant strain (lacking mtDNA) to arsenic provides further evidence that this death process involves mitochondria. In addition, hypersensitivity of Delta sod1 to arsenic suggests the critical role of ROS. Cell death and DNA fragmentation decreased in a Delta yca1 deletion mutant, indicating the participation of yeast caspase-1 protein in apoptosis. The implications of these findings for arsenic-induced apoptosis are discussed.