title: BDE-47 causes developmental retardation with down-regulated expression profiles of ecdysteroid signaling pathway-involved nuclear receptor (NR) genes in the copepod Tigriopus japonicus.
abstract: 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is a persistent organic pollutant (POP) in marine environments. Despite its adverse effects (e.g. developmental retardation) in ecdysozoa, the effects of BDE-47 on transcription of ecdysteroid signaling pathway-involved-nuclear receptor (NR) genes and metamorphosis-related genes have not been examined in copepods. To examine the deleterious effect of BDE-47 on copepod molting and metamorphosis, BDE-47 was exposed to the harpacticoid copepod Tigriopus japonicus, followed by monitoring developmental retardation and transcriptional alteration of NR genes. The developmental rate was significantly inhibited (P<0.05) in response to BDE-47 and the agricultural insecticide gamma-hexachlorocyclohexane. Conversely, the ecdysteroid agonist ponasterone A (PoA) led to decreased molting and metamorphosis time (P<0.05) from the nauplius stage to the adult stage. In particular, expression profiles of all NR genes were the highest at naupliar stages 5-6 except for SVP, FTZ-F1, and HR96 genes. Nuclear receptor USP, HR96, and FTZ-F1 genes also showed significant sex differences (P<0.05) in gene expression levels over different developmental stages, indicating that these genes may be involved in vitellogenesis. NR gene expression patterns showed significant decreases (P<0.05) in response to BDE-47 exposure, implying that molting and metamorphosis retardation is likely associated with NR gene expression. In summary, BDE-47 leads to molting and metamorphosis retardation and suppresses transcription of NR genes. This information will be helpful in understanding the molting and metamorphosis delay mechanism in response to BDE-47 exposure.
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Dae-Sik
authors.initials: DS
authors.lastname: Hwang
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Jeonghoon
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Eun-Ji
authors.initials: EJ
authors.lastname: Won
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Duck-Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
authors.forename: Chang-Bum
authors.initials: CB
authors.lastname: Jeong
authors.affiliation: Marine Ecological Risk Assessment Center, West Sea Fisheries Research Institute, National Fisheries Research & Development Institute, Incheon 46083, South Korea.
authors.forename: Un-Ki
authors.initials: UK
authors.lastname: Hwang
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Bingsheng
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea.
authors.forename: Joonho
authors.initials: J
authors.lastname: Choe
authors.affiliation: Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea. Electronic address: jslee2@skku.edu.
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000818:Animals; D033342:Copepoda / Q000187:drug effects* / Q000502:physiology; D015536:Down-Regulation / Q000187:drug effects*; D026461:Ecdysteroids / Q000378:metabolism*; D005260:Female; D005819:Genetic Markers; D055768:Halogenated Diphenyl Ethers / Q000633:toxicity*; D008297:Male; D008675:Metamorphosis, Biological / Q000187:drug effects* / Q000235:genetics; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D026461:Ecdysteroids; D005819:Genetic Markers; D055768:Halogenated Diphenyl Ethers; D018160:Receptors, Cytoplasmic and Nuclear; D014874:Water Pollutants, Chemical; C511295:2,2',4,4'-tetrabromodiphenyl ether
keywords: BDE-47; Copepod Tigriopus japonicus; Ecdysteroid signaling pathway; Metamorphosis; Molting; Nuclear receptor