Gene expression profiles in the testis associated with testis–ova in adult Japanese medaka (Oryziaslatipes) exposed to 17α-ethinylestradiol

• Published in: Chemosphere (Oxford) Vol. 87; no. 7; pp. 668 - 674
• Main Authors: Hirakawa, Ikumi, Miyagawa, Shinichi, Katsu, Yoshinao, Kagami, Yoshihiro, Tatarazako, Norihisa, Kobayashi, Tohru, Kusano, Teruhiko, Mizutani, Takeshi, Ogino, Yukiko, Takeuchi, Takashi, Ohta, Yasuhiko, Iguchi, Taisen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2012; Elsevier
• Subjects: 17α-Ethinylestradiol; Agnatha. Pisces; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Applied ecology; benzoates; Biological and medical sciences; brain; Ecotoxicology, biological effects of pollution; Endocrine Disruptors - metabolism; Endocrine Disruptors - toxicity; estradiol; Ethinyl Estradiol - metabolism; Ethinyl Estradiol - toxicity; fish; Fish Proteins - genetics; Fresh water ecosystems; Fundamental and applied biological sciences. Psychology; gene expression; Gene Expression Profiling; General aspects; genes; genetic markers; liver; Liver - metabolism; Male; Medaka; Microarray; microarray technology; Oocytes; Oryzias latipes; Ovum; Synecology; testes; Testis - drug effects; Testis - growth & development; Testis - metabolism; Testis - pathology; Testis–ova; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; vitellogenin; Vitellogenins - metabolism; Water Pollutants, Chemical - metabolism; Water Pollutants, Chemical - toxicity; zona pellucida; Zona pellucida genes; Medaka; Testis–ova; 17α-Ethinylestradiol; Zona pellucida genes; Microarray; Ethinylestradiol; Testis―ova; Gene expression; Testicle; Zona pellucida; Freshwater environment; Vertebrata; Gene; Pisces; Oryzias latipes; Sex steroid hormone; Organic compounds
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2011.12.047

► We analyzed testis–ova marker genes in the testis of estrogen-exposed adult medaka. ► Testis–ova were induced by ethinylestradiol and estradiol benzoate. ► Microarray revealed up-regulation of zona pellucida genes in the testis with oocytes. ► These genes can be used as marker genes for detection of testis–ova in male medaka. The occurrence of oocytes in the testis (testis–ova) of several fish species is often associated with exposure of estrogenic chemicals. However, induction mechanisms of the testis–ova remain to be elucidated. To develop marker genes for detecting testis–ova in the testis, adult male medaka were exposed to nominal concentration of 100ngL−1 of 17α-ethinylestradiol (EE2) for 3–5weeks, and 800ng estradiol benzoate (EB) for 3weeks (experiment I), and a measured concentration of 20ngL−1 EE2 for 1–6weeks (experiment II). Histological analysis was performed for the testis, and microarray analyses were performed for the testis, liver and brain. Microarray analysis in the estrogen-exposed medaka liver showed vitellogenin and choriogenin as estrogen responsive genes. Testis–ova were induced in the testis after 4weeks of exposure to 100ngL−1 EE2, 3weeks of exposure to 800ngEB, and 6weeks of exposure to 20ngL−1 EE2. Microarray analysis of estrogen-exposed testes revealed up-regulation of genes related to zona pellucida (ZP) and the oocytes marker gene, 42Sp50. Using quantitative RT-PCR we confirmed that Zpc5 gene can be used as a marker for the detection of testis–ova in male medaka.