Generation and propagation of yeast prion [URE3] are elevated under electromagnetic field
In this study, we studied the effect of 2.0 GHz radio frequency electromagnetic field (RF-EMF) and 50 Hz extremely low frequency electromagnetic field (ELF-EMF) exposure on prion generation and propagation using two budding yeast strains, NT64C and SB34, as model organisms. Under exposure to RF-EMF or ELF-EMF, the de novo generation and propagation of yeast prions [URE3] were elevated in both strains. The elevation increased over time, and the effects of ELF-EMF occurred in a dose-dependent manner. The transcription and expression levels of the molecular chaperones Hsp104, Hsp70-Ssa1/2, and Hsp40-Ydj1 were not statistically significantly changed after exposure. Furthermore, the levels of ROS, as well as the activities of superoxide dismutase (SOD) and catalase (CAT), were significantly elevated after short-term, but not long-term exposure. This work demonstrated for the first time that EMF exposure could elevate the de novo generation and propagation of yeast prions and supports the hypothesis that ROS may play a role in the effects of EMF on protein misfolding. The effects of EMF on protein folding and ROS levels may mediate the broad effects of EMF on cell function.
KeywordsPrion RF-EMF URE3 ELF-EMF ROS
We express our gratitude to Dr. Gary Jones (NUI Maynooth, Ireland) for kindly providing the yeast strains. The valuable assistance of Mr. Shen Tian on painting of Fig. 9 is gratefully acknowledged.
KWL and HYL performed all experiments. CJY, HYL, and KWL constructed and maintained the exposure systems. HYL conceived the study. HYL, KWL, and PC wrote the manuscript. PC led the project and reviewed the manuscript.
This work was supported by the Scientific Equipment Development Project of the Chinese Academy of Sciences (CAS) (YZ201104&YZ201205), the Xiamen Science and Technology Plans Project (3502Z20126012), the National Natural Science Foundation of China (31270888), and the Natural Science Foundation of Fujian Province (2012J01157).
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