title: Detecting genome-wide gene transcription profiles associated with high pollution burden in the critically endangered European eel.
abstract: The European eel illustrates an example of a critically endangered fish species strongly affected by human stressors throughout its life cycle, in which pollution is considered to be one of the factors responsible for the decline of the stock. The objective of our study was to better understand the transcriptional response of European eels chronically exposed to pollutants in their natural environment. A total of 42 pre-migrating (silver) female eels from lowly, highly and extremely polluted environments in Belgium and, for comparative purposes, a lowly polluted habitat in Italy were measured for polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and brominated flame retardants (BFRs). Multipollutant level of bioaccumulation was linked to their genome-wide gene transcription using an eel-specific array of 14,913 annotated cDNAs. Shared responses to pollutant exposure were observed when comparing the highly polluted site in Belgium with the relatively clean sites in Belgium and Italy. First, an altered pattern of transcription of genes was associated with detoxification, with a novel European eel CYP3A gene and gluthatione S-transferase transcriptionally up-regulated. Second, an altered pattern of transcription of genes associated with the oxidative phosphorylation pathway, with the following genes involved in the generation of ATP being transcriptionally down-regulated in individuals from the highly polluted site: NADH dehydrogenase, succinate dehydrogenase, ubiquinol-cytochrome c reductase, cytochrome c oxidase and ATP synthase. Although we did not measure metabolism directly, seeing that the transcription level of many genes encoding enzymes involved in the mitochondrial respiratory chain and oxidative phosphorylation were down-regulated in the highly polluted site suggests that pollutants may have a significant effect on energy metabolism in these fish.
authors.affiliation: Department of Biology, University of Padova, I-35131 Padova, Italy.
authors.forename: J M
authors.initials: JM
authors.lastname: Pujolar
authors.forename: M
authors.initials: M
authors.lastname: Milan
authors.forename: I A M
authors.initials: IA
authors.lastname: Marino
authors.forename: F
authors.initials: F
authors.lastname: Capoccioni
authors.forename: E
authors.initials: E
authors.lastname: Ciccotti
authors.forename: C
authors.initials: C
authors.lastname: Belpaire
authors.forename: A
authors.initials: A
authors.lastname: Covaci
authors.forename: G
authors.initials: G
authors.lastname: Malarvannan
authors.forename: T
authors.initials: T
authors.lastname: Patarnello
authors.forename: L
authors.initials: L
authors.lastname: Bargelloni
authors.forename: L
authors.initials: L
authors.lastname: Zane
authors.forename: G E
authors.initials: GE
authors.lastname: Maes
mesh_terms: D000811:Anguilla / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001530:Belgium; D017753:Ecosystem; D056727:Endangered Species; D004784:Environmental Monitoring; D005411:Flame Retardants / Q000633:toxicity; D015870:Gene Expression / Q000187:drug effects*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects*; D055106:Genome-Wide Association Study; D059014:High-Throughput Nucleotide Sequencing; D006842:Hydrocarbons, Brominated / Q000633:toxicity; D006843:Hydrocarbons, Chlorinated / Q000633:toxicity; D007558:Italy; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010575:Pesticides / Q000633:toxicity; D011078:Polychlorinated Biphenyls / Q000633:toxicity; D059467:Transcriptome / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D005411:Flame Retardants; D006842:Hydrocarbons, Brominated; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls