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Published on: May 21, 2020
Ionizing radiation induces a Yap1-dependent peroxide stress response in yeast
Mikael Molin1, Jean-Philippe Renault, Gilles Lagniel
1Laboratoire de PhysioGénomique, SBGM/DBJC/DSV, CEA/Saclay, F-91191, Gif-sur-Yvette Cedex, France.
Free Radical Biology & Medicine
|June 15, 2007
Summary
Ionizing radiation (IR) induces oxidative stress in yeast, primarily through hydrogen peroxide (H2O2). While H2O2 activates the Yap1 stress regulator, it doesn't fully explain IR toxicity.
Area of Science:
- Cellular biology
- Radiation biology
- Biochemistry
Background:
- DNA damage repair is crucial for ionizing radiation (IR) tolerance.
- IR-induced DNA lesions are often linked to oxidative stress.
- Understanding cellular responses to IR is vital for radiation protection and therapy.
Purpose of the Study:
- Investigate the physiological effects of IR in Saccharomyces cerevisiae.
- Determine the role of oxidative stress in IR response.
- Elucidate the mechanism of Yap1 activation by IR.
Main Methods:
- Protein expression profiling in yeast cells exposed to electron pulse irradiation.
- Analysis of Yap1 activation and its dependence on oxidative stress regulators.
- Manipulation of reactive oxygen species (ROS) production during irradiation.
Main Results:
- IR induced transient antioxidant enzyme expression in wild-type yeast, indicating oxidative stress.
- Yap1 activation was dependent on the peroxide sensor Orp1/Gpx3 and required H2O2 production.
- Yap1 could not be activated by hydroxyl radicals, suggesting specificity for H2O2.
- Yap1 activation did not appear to be the primary factor in cellular IR tolerance.
Conclusions:
- IR exposure leads to in vivo peroxide stress in yeast.
- Hydrogen peroxide is a key mediator of IR-induced Yap1 activation.
- The H2O2 produced during IR is insufficient to account for the overall toxicity of IR.
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