title: Effect of cadmium exposure on expression of antioxidant gene transcripts in the river pufferfish, Takifugu obscurus (Tetraodontiformes).
abstract: Cadmium (Cd) is a non-essential toxic heavy metal with the potential to induce oxidative stress. Cd toxicity and its capacity for accumulation in aquatic habitats have earned its recognition as a pollutant of immediate and widespread concern. To obtain a better understanding of oxidative stress-associated gene expression in different tissues, six antioxidant genes such as catalase (CAT), glutathione reductase (GR), glutathione peroxidase 1a (GPx1a), glutathione peroxidase 1b (GPx1b), Cu/Zn superoxide dismutase (Cu/Zn-SOD), and Mn superoxide dismutase (Mn-SOD) were cloned and fully sequenced in the river pufferfish, Takifugu obscurus. On tissue specific mRNA expression, the liver showed the highest expression when compared to other tissues, even though each antioxidant gene showed different modes of expression patterns in the examined tissues. Of the various antioxidant genes, GR was the most highly expressed in the liver, followed by CAT, GPx1, and Cu/Zn-SOD. For the time-course experiment, all the antioxidant genes were significantly induced over time except for Cu/Zn-SOD in the liver, and there was a 5-fold induction in hepatic GR, CAT, and Mn-SOD mRNA compared to the control. These findings indicate that the liver of T. obscurus has a robust antioxidant system. In addition, these results suggest that Cd exposure modulates the expression of antioxidant genes, and would indicate that the antioxidant genes would be a relevant biomarker of trace metal pollution such as Cd exposure in T. obscurus.
authors.affiliation: National Research Lab of Marine Molecular and Environmental Bioscience, Department of Chemistry, College of Natural Sciences, Hanyang University, Seoul 133-791, South Korea.
authors.forename: Jin-Hyoung
authors.initials: JH
authors.lastname: Kim
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Rhee
authors.forename: Jin-Seon
authors.initials: JS
authors.lastname: Lee
authors.forename: Hans-Uwe
authors.initials: HU
authors.lastname: Dahms
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
authors.forename: Kyung-Nam
authors.initials: KN
authors.lastname: Han
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D002104:Cadmium / Q000633:toxicity*; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D005980:Glutathione Reductase / Q000235:genetics / Q000378:metabolism; D008658:Inactivation, Metabolic; D012333:RNA, Messenger / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D023741:Takifugu / Q000235:genetics / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D000094765:Glutathione Peroxidase GPX1
chemical_list: D000975:Antioxidants; D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; D002104:Cadmium; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D000094765:Glutathione Peroxidase GPX1