title: The agrochemical fungicide triadimefon induces abnormalities in Xenopus laevis embryos.
abstract: The dysmorphogenic activity of the triazole fungicide triadimefon (FON) has been evaluated using Xenopus laevis development. Embryos, exposed to 500 μM FON during early neurulation phases (stages 13-17, Nieuwkoop and Faber), were allowed to develop until stage 47. Larvae revealed serious craniofacial defects, bent forebrain, and abnormal hindbrain segmentation. CRABP and CYP26 (markers related to retinoic acid homeostasis) gene and protein expression and protein distribution have been evaluated at stage 17 and at the end of the branchial arch morphogenesis (stage 27) by real-time PCR, western blot and whole-mount immunostaining. A significant increase of CYP26 transcript has been observed at both embryonic stages. A co-localization of the two markers has been observed at the cephalic region. Embryos exposed to FON showed abnormal distribution of positive tissues. Due to the strict similarity of these results with those previously described in rodents, a FON-related alteration of mechanism conserved during vertebrate evolution is suggested.
authors.affiliation: Università di Milano, Department of Biology, Via Celoria 26, 20133 Milan, Italy. francesca.direnzo@unimi.it
authors.forename: Francesca
authors.initials: F
authors.lastname: Di Renzo
authors.forename: Renato
authors.initials: R
authors.lastname: Bacchetta
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Sangiorgio
authors.forename: Andrea
authors.initials: A
authors.lastname: Bizzo
authors.forename: Elena
authors.initials: E
authors.lastname: Menegola
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000209:etiology* / Q000235:genetics; D000818:Animals; D015153:Blotting, Western; D019465:Craniofacial Abnormalities / Q000139:chemically induced; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004625:Embryo, Nonmammalian / Q000002:abnormalities / Q000187:drug effects; D005659:Fungicides, Industrial / Q000633:toxicity*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D007150:Immunohistochemistry; D007814:Larva / Q000187:drug effects; D009024:Morphogenesis / Q000187:drug effects / Q000235:genetics; D054261:Neurulation / Q000187:drug effects / Q000235:genetics; D016133:Polymerase Chain Reaction; D016548:Prosencephalon / Q000002:abnormalities / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000235:genetics; D000072516:Retinoic Acid 4-Hydroxylase; D012249:Rhombencephalon / Q000002:abnormalities / Q000187:drug effects; D014230:Triazoles / Q000633:toxicity*; D014982:Xenopus laevis / Q000196:embryology* / Q000235:genetics
chemical_list: D005659:Fungicides, Industrial; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D014230:Triazoles; C082927:retinoic acid binding protein I, cellular; C032910:triadimefon; D003577:Cytochrome P-450 Enzyme System; D000072516:Retinoic Acid 4-Hydroxylase