title: Identification of three doublesex genes in the monogonont rotifer Brachionus koreanus and their transcriptional responses to environmental stressor-triggered population growth retardation.
abstract: Doublesex and Mab-3-related transcription factor (Dmrt) gene family members have rarely been identified or characterized in aquatic invertebrates. In this study, we identified and characterized three DMdomain-containing genes - Dmrt11E, Dmrt93B, and Dmrt99B - in the monogonont rotifer, Brachionus koreanus. DMdomains of the proteins encoded by the B.koreanus Dmrt (Bk-Dmrt) genes had high similarities to DM domains of other invertebrate species. To understand the potential effects of environmental stressors on the transcriptional expression of Dmrt genes in rotifers, we exposed B.koreanus to a wide range of UV-B radiation and different concentrations of benzo[a]pyrene (B[a]P) over different time courses. Transcript levels of all Bk-Dmrt genes decreased significantly in response to relatively high doses of UV-B irradiation, and were also downregulated in response to exposure to UV-B radiation over time. Transcript levels of all Bk-Dmrt genes were downregulated in response to B[a]P exposure for 24h. This decrease in expression of all Bk-Dmrt genes was concomitant with the growth retardation induced by UV-B and B[a]P exposure. We concluded that both environmental stressors have detrimental effects on transcriptional regulation of all Bk-Dmrt genes, especially relatively high doses of these stressors, leading to growth retardation. However, further studies are required to better understand the potential role of Dmrt genes in environmental stressor-triggered growth retardation in the rotifer B.koreanus.
authors.affiliation: Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746, South Korea.
authors.forename: Bo-Mi
authors.initials: BM
authors.lastname: Kim
authors.affiliation: Department of Chemistry, College of Natural Sciences, Hanyang University, Seoul 133-791, South Korea.
authors.forename: Chang-Bum
authors.initials: CB
authors.lastname: Jeong
authors.affiliation: Division of Life Sciences, Korea Polar Research Institute, Korea Institute of Ocean Science and Technology, Incheon 406-840, South Korea.
authors.forename: Il-Chan
authors.initials: IC
authors.lastname: Kim
authors.affiliation: Division of Life Sciences, Korea Polar Research Institute, Korea Institute of Ocean Science and Technology, Incheon 406-840, South Korea.
authors.forename: Joung Han
authors.initials: JH
authors.lastname: Yim
authors.affiliation: Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 133-791, South Korea.
authors.forename: Yong Sung
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Marine Science, College of Natural Sciences, Incheon National University, Incheon 406-772, South Korea. Electronic address: jsrhee@incheon.ac.kr.
authors.forename: Jae-Sung
authors.initials: JS
authors.lastname: Rhee
authors.affiliation: Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746, South Korea. Electronic address: jslee2@skku.edu.
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D008969:Molecular Sequence Data; D011158:Population Growth; D012403:Rotifera / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D059467:Transcriptome; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014157:Transcription Factors; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene
keywords: B[a]P; Brachionus koreanus; DM-domain; Dmrt; UV-B