title: Methyl mercury suppresses the formation of the tail primordium in developing zebrafish embryos.
abstract: The objective of this study was to characterize the mechanisms of action of the model environmental toxicant methyl mercury (MeHg) in the zebrafish embryo. Zebrafish embryos were exposed to MeHg, and the effective concentration and window of exposure were determined in wild-type and fluorescent reporter transgenic zebrafish embryos. Genes were systematically assessed for altered expression in response to MeHg by in situ hybridization. MeHg impairs development of the fin fold and the tail fin primordium. Alterations in transgene expression were noted at 6 microg/l MeHg, making this shh:gfp line the most sensitive biosensor of MeHg exposure. The matrix metalloproteases mmp9 and mmp13 and eight other genes are induced in the embryonic tail in response to MeHg. Our data suggest that MeHg impairs tail development at least partially by activation of the tissue remodeling proteases Mmp9 and Mmp13.
authors.affiliation: Institute of Toxicology and Genetics Forschungszentrum Karlsruhe Karlsruhe Institute of Technology 76021 Karlsruhe, Germany.
authors.forename: Lixin
authors.initials: L
authors.lastname: Yang
authors.forename: Nga Yu
authors.initials: NY
authors.lastname: Ho
authors.forename: Ferenc
authors.initials: F
authors.lastname: Müller
authors.forename: Uwe
authors.initials: U
authors.lastname: Strähle
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000187:drug effects* / Q000196:embryology; D005121:Extremities / Q000196:embryology; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D017403:In Situ Hybridization; D053509:Matrix Metalloproteinase 13 / Q000235:genetics / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism; D008767:Methylmercury Compounds / Q000633:toxicity*; D013623:Tail / Q000187:drug effects / Q000196:embryology; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000502:physiology*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D029961:Zebrafish Proteins; D053509:Matrix Metalloproteinase 13; D020780:Matrix Metalloproteinase 9