title: Acute effects of heavy metals on the expression of glutathione-related antioxidant genes in the marine ciliate Euplotes crassus.
abstract: Euplotes crassus, a single-celled eukaryote, is directly affected by environmental contaminants. Here, exponentially cultured E. crassus were exposed to cadmium, copper, lead, and zinc and then the reactive oxygen species (ROS) and total glutathione (GSH) levels were measured. Subsequently, the transcriptional modulation of glutathione peroxidase (GPx) and glutathione reductase (GR) were estimated by quantitative RT-PCR. After an 8-h exposure, significantly higher increases in the relative ROS and total GSH levels were observed in exposed group, compared to the controls. Real-time PCR data revealed that the expression levels of GPx and GR mRNA were sensitively modulated within 8h of exposure to all heavy metals. These findings suggest that these genes may be involved in cellular defense mechanisms by modulating their gene expression against heavy metal-induced oxidative stress. Thus, they may be useful as potential molecular biomarkers to assess sediment environments for contaminants.
authors.affiliation: Department of Life Science, College of Natural Science, Sangmyung University, Seoul 110-743, South Korea.
authors.forename: Se-Hun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Deep-sea and Seabed Resources Research Division, Korea Institute of Ocean Science and Technology (KIOST), Ansan 426-744, South Korea.
authors.forename: Se-Joo
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746, South Korea.
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Life Science, College of Natural Science, Sangmyung University, Seoul 110-743, South Korea. Electronic address: ymlee70@smu.ac.kr.
authors.forename: Young-Mi
authors.initials: YM
authors.lastname: Lee
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D002104:Cadmium / Q000633:toxicity; D003300:Copper / Q000633:toxicity; D016812:Euplotes / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D007854:Lead / Q000633:toxicity; D019216:Metals, Heavy / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015032:Zinc / Q000633:toxicity
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D019216:Metals, Heavy; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D003300:Copper; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005978:Glutathione; D015032:Zinc
keywords: Euplotes crassus; Glutathione; Heavy metals; Marine ciliate; Reactive oxygen species