title: Dose-dependent effects of metals on gene expression in the sydney rock oyster, Saccostrea glomerata.
abstract: In the current study, we tested the effects of common environmental contaminants (the metals zinc and lead) on gene expression in Sydney rock oysters (Saccrostrea glomerata). Oysters were exposed to a range of metal concentrations under controlled laboratory conditions. The expression of 14 putative stress response genes was then measured using quantitative, real-time (q) PCR. The expression of all 14 genes was significantly affected (p < 0.05 vs. nonexposed controls) by at least one of the metals, and by at least one dose of metal. For 5 of the 14 target genes (actin, calmodulin, superoxide dismutase, topoisomerase I, and tubulin) the alteration of expression relative to controls was highest at intermediate (rather than high) doses of metals. Such responses may reflect adaptive (acclimation) reactions in gene expression at low to intermediate doses of contaminants, followed by a decline in expression resulting from exposure at higher doses. The data are discussed in terms of the intracellular pathways affected by metal contamination, and the relevance of such gene expression data to environmental biomonitoring.
authors.affiliation: Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia.|Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia.
authors.forename: Daisy A
authors.initials: DA
authors.lastname: Taylor
authors.affiliation: Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia.
authors.forename: Sham V
authors.initials: SV
authors.lastname: Nair
authors.affiliation: Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia.|Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia.
authors.forename: Emma L
authors.initials: EL
authors.lastname: Thompson
authors.affiliation: Department of Biological Sciences, Macquarie University, New South Wales, 2109, Australia.|Sydney Institute of Marine Science, Chowder Bay, New South Wale, 2088, Australia.
authors.forename: David A
authors.initials: DA
authors.lastname: Raftos
mesh_terms: D000818:Animals; D002712:Chlorides / Q000633:toxicity; D004784:Environmental Monitoring; D007854:Lead / Q000633:toxicity; D008670:Metals / Q000737:chemistry / Q000633:toxicity*; D010125:Ostreidae / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D059467:Transcriptome / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*; D017967:Zinc Compounds / Q000633:toxicity
chemical_list: D002712:Chlorides; D008670:Metals; D014874:Water Pollutants, Chemical; D017967:Zinc Compounds; D007854:Lead; C029891:lead chloride; C016837:zinc chloride
keywords: Saccostrea glomerata; biomarker genes; dose-response; metals; real-time PCR