title: Thyroid hormone related gene transcription in southern sand flathead (Platycephalus bassensis) is associated with environmental mercury and arsenic exposure.
abstract: Arsenic (As) and mercury (Hg) are ubiquitous elements known to disrupt thyroid function in vertebrates. To explore the underlying mechanisms of Hg and As on the fish thyroid system, we investigated the associations between muscle concentrations of Hg and As with thyroid-related gene transcription in flathead (Platycephalus bassensis) from a contaminated estuary. We sampled fish at several sites to determine the hepatic expression of genes including deiodinases (D1 and D2), transthyretin (TTR), thyroid hormone receptors (TRα and TRβ) and related them to Hg and As levels in the same individuals. Negative correlations were observed between Hg levels and D2, TTR, TRα and TRβ, whereas positive associations were found between As concentrations and TTR and TRβ. These results suggest that Hg and As exposures from environmental pollution affect the regulation of genes important for normal thyroid function in fish. These thyroid-related genes could be used as biomarkers for monitoring environmental thyroid-hormone disrupting chemicals.
authors.affiliation: Institute for Marine and Antarctic Studies, University of Tasmania, Locked Bag 1370, Launceston, TAS, 7250, Australia. fudingkun@gmail.com.
authors.forename: Dingkun
authors.identifier: http://orcid.org/0000-0003-1514-224X
authors.initials: D
authors.lastname: Fu
authors.affiliation: Institute for Marine and Antarctic Studies, University of Tasmania, Locked Bag 1370, Launceston, TAS, 7250, Australia.
authors.forename: Melanie
authors.initials: M
authors.lastname: Leef
authors.affiliation: Institute for Marine and Antarctic Studies, University of Tasmania, Locked Bag 1370, Launceston, TAS, 7250, Australia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Nowak
authors.affiliation: Institute for Marine and Antarctic Studies, University of Tasmania, Locked Bag 1370, Launceston, TAS, 7250, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Bridle
mesh_terms: D000818:Animals; D001151:Arsenic / Q000633:toxicity*; D004784:Environmental Monitoring; D005399:Fishes; D008628:Mercury / Q000633:toxicity*; D013963:Thyroid Hormones / Q000235:genetics*; D014158:Transcription, Genetic / Q000187:drug effects*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D013963:Thyroid Hormones; D014874:Water Pollutants, Chemical; D008628:Mercury; D001151:Arsenic
keywords: Arsenic; Biomarker; Fish; Gene expression; Mercury; Thyroid-related genes