Cadmium-induced synthesis of HSP70 and a role of glutathione in Euglena gracilis.
The effect of cadmium-induced oxidative stress, with or without glutathione supplementation, was investigated in the single cell eukaryotic phytoflagellate, Euglena gracilis strains Z and its achlorophyllous mutant SMZ as experimental models. Both these strains actively synthesize thiols to prevent or resist cadmium toxicity. The content of glutathione, as a representative antioxidant, was also examined in both strains. Exposure to cadmium induced heat-shock protein 70 (HSP70) synthesis in both strains of E. gracilis. Glutathione supplementation also induced HSP70. Overall, these results indicate that glutathione was closely linked to the induction of stress-related proteins. The sensitivity to cadmium-stress was higher in strain Z than SMZ. The results suggest that chloroplasts may have a role in the regulation of HSP70 expression. The relationship between HSP70 and GSH levels is still far from understood, and further research may shed light upon their up-regulation in the presence of Cd.
Watanabe
Masumi
M
Laboratory of Food Wholesomeness and Soundness, Division of Life Sciences, Graduate School of Fisheries Sciences, Hokkaido University, Hokkaido, Japan.
Suzuki
Tetsuya
T
D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D019256:Cadmium Chloride / Q000633:toxicity; D005056:Euglena gracilis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D005978:Glutathione / Q000494:pharmacology / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D009154:Mutation; D018384:Oxidative Stress / Q000187:drug effects
D018840:HSP70 Heat-Shock Proteins; D002104:Cadmium; D005978:Glutathione; D019256:Cadmium Chloride