60co gamma irradiator

Cells of Chlorella sp. ArM0029B were cultured at 25°C in Tris–acetate–phosphate (TAP) medium (Harris, 1989 ). Mutants of this species were generated by irradiating cells with 300 Gy (100 Gy per hour) in a ⁶⁰Co gamma irradiator (150 TBq Capacity; ACEL, Nordion, Ottawa, ON, Canada) at the Korean Atomic Energy Research Institute. A mutant tolerant to HL intensity was isolated from the mutant library by growing cultures under intermediate light intensity (300–350 μmol m^-2 s^-1). The mutant was named to “CAC1”. Cultures were grown under low [referred to as low light (LL); 50–80 μmol m^-2 s^-1] or HL (650–800 μmol m^-2 s^-1) intensities. Growth rate was assessed by counting cells under a microscope after 0.5 × 10⁶ cells ml^-1 was inoculated in 50 ml culture.

To examine plant responses to radiation, rice seeds (Oryza sativa
cv. Ilpoom) were exposed to gamma- irradiation, ion beams, and
cosmic rays as described by Hwang et
al. (2014). Briefly, for gamma-irradiation treatment,
mature seeds were exposed to a dose of 200 Gy generated by a ⁶⁰Co
gamma irradiator (maximum output, 150 TBq; ACEL, Nordion, Ottawa, ON, Canada) at
the Korea Atomic Energy Research Institute. The ion beam treatment consisted of
irradiation with 220 MeV carbon ions (LET 107 keV/um), at a dose of 40 Gy,
generated by an AVF cyclotron (Japan Atomic Energy Agency, Takasaki, Japan).
Exposure to cosmic rays was achieved by placing samples on “Shijian-8”, an
unmanned breeding spacecraft, for 15 days. For transcriptional expression
analysis, irradiated seeds were cultured on half-strength MS medium and grown
for 9 weeks at 24 °C, photoperiod of 16 h light/8 h dark, and 70% humidity.

Head and neck squamous cell carcinoma cell lines SCC61 (radiosensitive) derived from a glossal tumor (Weichselbaum et al., 1986), JSQ3 (radioresistant) derived from a nasal vestibule tumor, and SQ20B (radioresistant) derived from a laryngeal tumor (Weichselbaum et al., 1988) were grown in DMEM/F‐12 media (Life Technologies, Grand Island, NY, USA) supplemented with 20% fetal bovine serum (Denville Scientific) and penicillin/streptomycin (100 units·mL⁻¹, 100 mg·mL⁻¹, Life Technologies). Cultures were maintained at 37 °C in a humidified atmosphere containing 5% CO₂ until approximately 70% confluence was reached. Authenticity was confirmed by short tandem repeats (STR) profiling (Center for Genomic Research, University of Illinois at Chicago). All the cell lines tested negative for mycoplasma contamination.
Pitavastatin calcium (PIT) was obtained from Atomole. Simvastatin, pravastatin, atorvastatin, lovastatin, and rosuvastatin were from the NIH Clinical Collection (BioFocus, Mechelen, Belgium). FTI (FTI‐276) and GGTI (GGTI‐2147) inhibitors were from CalBiochem.
Cellular irradiation was delivered using a ⁶⁰Co gamma irradiator (GammaCell, MDS Nordion) with a dose rate ranging from 9.4 to 7.6 cGy·s⁻¹, depending on the date of the experiment.