title: Modulatory effect of environmental endocrine disruptors on N-ras oncogene expression in the hermaphroditic fish, Kryptolebias marmoratus.
abstract: Kryptolebias marmoratus is the only known internally self-fertilizing vertebrate. It shows high susceptibility to many chemical carcinogens and has been proposed as a potential cancer model species alternative to mammals. Since use of this fish species is expected to rise in cancer research, regulation of oncogenes from K. marmoratus needs proper understanding. We cloned and deduced full-length sequence of cDNA of N-ras oncogene from K. marmoratus. Study of expression profile of N-ras by using quantitative real-time RT-PCR revealed that brain had the highest level of expression compared to other tissues. Some embryonic stages showed more N-ras expression than juveniles and adults. Exposure to two environmental endocrine disrupting chemicals (EDCs), bisphenol A (BPA) and 4-nonylphenyl (NP) caused up-regulation of N-ras in gonad, intestine and liver of hermaphrodite K. marmoratus. It is suggested that K. marmoratus may be a suitable model species for oncogene expression studies. The observed EDC-induced expression of N-ras supports the assumption that EDC exposure may predispose the host to the risk of environmental carcinogenesis.
authors.affiliation: Department of Chemistry and the National Research Lab of Marine Molecular and Environmental Bioscience, College of Natural Sciences, Hanyang University, Seoul 133-791, South Korea.
authors.forename: Young-Mi
authors.initials: YM
authors.lastname: Lee
authors.forename: Sheikh
authors.initials: S
authors.lastname: Raisuddin
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Rhee
authors.forename: Jang-Seu
authors.initials: JS
authors.lastname: Ki
authors.forename: Il-Chan
authors.initials: IC
authors.lastname: Kim
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001559:Benzhydryl Compounds; D015197:Carcinogenicity Tests; D003001:Cloning, Molecular; D052244:Endocrine Disruptors / Q000633:toxicity*; D004784:Environmental Monitoring / Q000379:methods; D015870:Gene Expression / Q000187:drug effects*; D011905:Genes, ras; D057850:Hermaphroditic Organisms; D007695:Killifishes / Q000235:genetics* / Q000254:growth & development; D008969:Molecular Sequence Data; D010636:Phenols / Q000633:toxicity; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D019849:Sex Determination Processes; D014018:Tissue Distribution; D015854:Up-Regulation; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D010636:Phenols; D014874:Water Pollutants, Chemical; C041594:4-nonylphenol; C006780:bisphenol A; D000098826:Bisphenol A Compounds