Starvation for an essential amino acid induces apoptosis and oxidative stress in yeast.
Protracted starvation of auxotrophic Saccharomyces cerevisiae strains for an essential amino acid is commonly used to allow investigation of adaptive mutation mechanisms during starvation-induced cell cycle arrest. Under these conditions, the majority of cells dies during the first 6 days. We investigated starving cells for markers of programmed cell death and for the production of reactive oxygen species (ROS). We observed that protracted starvation for lysine or histidine resulted in an increasing number of cells exhibiting DNA fragmentation and chromatin condensation, thus an apoptotic phenotype. Not only respiration-competent cells but also respiratory deficient rho0 cells were able to undergo programmed cell death. In addition the starving cells rapidly exhibited indicators of oxidative stress, independently of their respiratory competence. These results indicate that starvation for an essential amino acid results in severe cell stress, which may finally be the trigger of programmed cell death.
Division of Molecular Genetics, Institute of Cancer Research, Medical University of Vienna, A-1090 Vienna, Austria.
Herfried
H
Eisler
Kai-Uwe
KU
Fröhlich
Erich
E
Heidenreich
D017209:Apoptosis / Q000502:physiology*; D006639:Histidine / Q000172:deficiency / Q000378:metabolism*; D020287:In Situ Nick-End Labeling; D008239:Lysine / Q000172:deficiency / Q000378:metabolism*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013997:Time Factors
D017382:Reactive Oxygen Species; D006639:Histidine; D008239:Lysine