title: Whole-Organism Transcriptomic Analysis Provides Mechanistic Insight into the Acute Toxicity of Emamectin Benzoate in Daphnia magna.
abstract: Emamectin benzoate (EMB) is an antisea lice chemical widely used in the aquaculture that may also unintentionally affect nontarget crustaceans in the environment. Although the adverse effects of this compound are well documented in various species, the full modes of action (MoAs) are still not well characterized. The current study was therefore conducted to characterize the MoAs of EMB and link perturbations of key toxicological pathways to adverse effects in the model freshwater crustacean Daphnia magna. Effects on molting and survival were determined after 48 h exposure to EMB, whereas global transcriptional changes and the ecdysone receptor (EcR) binding potency was determined to characterize the MoA. The results showed that the molting frequency and survival of D. magna decreased in a concentration-dependent manner, and the observed changes could not be attributed to direct interactions with the EcR. Major MoAs such as activation of glutamate-gated chloride channels and gamma-aminobutyric acid signaling, disruption of neuroendocrine regulation of molting, perturbation of energy homeostasis, suppression of DNA repair and induction of programmed cell death were observed by transcriptional analysis and successfully linked to the adverse effects. This study has demonstrated that acute exposure to intermediate and high pM levels of EMB may pose hazards to nontarget crustaceans in the aquatic environment.
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.
authors.forename: You
authors.initials: Y
authors.lastname: Song
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.
authors.forename: Jan Thomas
authors.initials: JT
authors.lastname: Rundberget
authors.affiliation: Department of Medical Biology, Faculty of Health Sciences, University of Tromsø-The Arctic University of Norway , NO-9037 Tromsø, Norway.
authors.forename: Linn Mari
authors.initials: LM
authors.lastname: Evenseth
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.|Norwegian University of Life Sciences (NMBU) , Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity (CERAD). P.O. Box 5003, N-1432 Ås, Oslo, Norway.
authors.forename: Li
authors.initials: L
authors.lastname: Xie
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.|Norwegian University of Life Sciences (NMBU) , Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity (CERAD). P.O. Box 5003, N-1432 Ås, Oslo, Norway.
authors.forename: Tânia
authors.initials: T
authors.lastname: Gomes
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.
authors.forename: Tore
authors.initials: T
authors.lastname: Høgåsen
authors.affiliation: Department of Basic Biology, Faculty of Life Science, SOKENDAI, Graduate University for Advanced Studies , 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan.|Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology (NIBB), National Institutes of Natural Sciences , 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan.
authors.forename: Taisen
authors.initials: T
authors.lastname: Iguchi
authors.affiliation: Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment , Gaustadalléen 21, N-0349 Oslo, Norway.|Norwegian University of Life Sciences (NMBU) , Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity (CERAD). P.O. Box 5003, N-1432 Ås, Oslo, Norway.
authors.forename: Knut Erik
authors.initials: KE
authors.lastname: Tollefsen
mesh_terms: D000818:Animals; D003621:Daphnia / Q000187:drug effects*; D007559:Ivermectin / Q000031:analogs & derivatives* / Q000633:toxicity; D018978:Molting / Q000187:drug effects; D059467:Transcriptome; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D005680:gamma-Aminobutyric Acid
chemical_list: D014874:Water Pollutants, Chemical; D005680:gamma-Aminobutyric Acid; D007559:Ivermectin; C108024:emamectin benzoate