Register      Login
Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Roles of forkhead box protein L2 (foxl2) during gonad differentiation and maintenance in a fish, the olive flounder (Paralichthys olivaceus)

Zhaofei Fan https://orcid.org/0000-0002-3449-1587 A B C , Yuxia Zou A B , Dongdong Liang A B C , Xungang Tan A B , Shuang Jiao A B , Zhihao Wu A B , Jun Li A B , Peijun Zhang A B and Feng You A B D
+ Author Affiliations
- Author Affiliations

A Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, PR China.

B Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology (Qingdao), 1 Wenhai Road, Qingdao 266237, PR China.

C University of Chinese Academy of Sciences, 19 (A) Yuquan Road, Beijing 100049, PR China.

D Corresponding author. Email: youfeng@qdio.ac.cn

Reproduction, Fertility and Development 31(11) 1742-1752 https://doi.org/10.1071/RD18233
Submitted: 4 October 2017  Accepted: 6 June 2019   Published: 20 September 2019

Abstract

As an important maricultured fish, the olive flounder Paralichthys olivaceus shows sex-dimorphic growth. Thus, the molecular mechanisms involved in sex control in P. olivaceus have attracted researchers’ attention. Among the sex-related genes, forkhead box protein L2 (foxl2) exhibits significant sex-dimorphic expression patterns and plays an important role in fish gonad differentiation and development. The present study first investigated the expression levels and promoter methylation dynamics of foxl2 during flounder gonad differentiation under treatments of high temperature and exogenous 17β-oestradiol (E2). During high temperature treatment, the expression of flounder foxl2 may be repressed via maintenance of DNA methylation. Then, flounder with differentiated testis at Stages I–II were treated with exogenous 5 ppm E2 or 5 ppm E2 + 150 ppm trilostane (TR) to investigate whether exogenous sex hormones could induce flounder sex reversal. The differentiated testis exhibited phenotypic variations of gonadal dysgenesis with upregulation of female-related genes (foxl2 and cytochrome P450 family 19 subfamily A (cyp19a)) and downregulation of male-related genes (cytochrome P450 family 11 subfamily B member 2 (cyp11b2), doublesex- and mab-3 related transcription factor 1 (dmrt1), anti-Mullerian hormone (amh) and SRY-box transcription factor 9 (sox9)). Furthermore, a cotransfection assay of the cells of the flounder Sertoli cell line indicated that Foxl2 was able alone or with nuclear receptor subfamily 5 group A member 2 (Nr5a2) jointly to upregulate expression of cyp19a. Moreover, Foxl2 and Nr5a2 repressed the expression of dmrt1. In summary, Foxl2 may play an important role in ovarian differentiation by maintaining cyp19a expression and antagonising the expression of dmrt1. However, upregulation of foxl2 is not sufficient to induce the sex reversal of differentiated testis.

Additional keywords: DNA methylation, high temperature and exogenous sex hormones, gene expression, gonad development.


References

Bai, J., Gong, W., Wang, C., Gao, Y., Hong, W., and Chen, S. X. (2016). Dynamic methylation pattern of cyp19a1a, core promoter during zebrafish ovarian folliculogenesis. Fish Physiol. Biochem. 42, 947–954.
Dynamic methylation pattern of cyp19a1a, core promoter during zebrafish ovarian folliculogenesis.Crossref | GoogleScholarGoogle Scholar | 26719066PubMed |

Baroiller, J. F., D’Cotta, H., and Saillant, E. (2009). Environmental effects on fish sex determination and differentiation. Sex Dev. 3, 118–135.
Environmental effects on fish sex determination and differentiation.Crossref | GoogleScholarGoogle Scholar | 19684457PubMed |

Boulanger, L., Pannetier, M., Gall, L., Allais-Bonnet, A., Elzaiat, M., Le Bourhis, D., Daniel, N., Richard, C., Cotinot, C., Ghyselinck, N. B., and Pailhoux, E. (2014). FOXL2 is a female sex-determining gene in the goat. Curr. Biol. 24, 404–408.
FOXL2 is a female sex-determining gene in the goat.Crossref | GoogleScholarGoogle Scholar | 24485832PubMed |

Devlin, R. H., and Nagahama, Y. (2002). Sex determination and sex differentiation in fish: an overview of genetic, physiological, and environmental influences. Aquaculture 208, 191–364.
Sex determination and sex differentiation in fish: an overview of genetic, physiological, and environmental influences.Crossref | GoogleScholarGoogle Scholar |

Fan, Z., You, F., Wang, L., Weng, S., Wu, Z., Hu, J., Zou, Y., Tan, X., and Zhang, P. (2014). Gonadal transcriptome analysis of male and female olive flounder (Paralichthys olivaceus). BioMed Res. Int. 2014, 291067.
Gonadal transcriptome analysis of male and female olive flounder (Paralichthys olivaceus).Crossref | GoogleScholarGoogle Scholar | 25197657PubMed |

Fan, Z., Zou, Y., Jiao, S., Tan, X., Liang, D., Zhang, P., and You, F. (2017). Significant association of cyp19a promoter methylation with environmental factors and gonadal differentiation in olive flounder Paralichthys olivaceus. Comp. Biochem. Physiol. A Mol. Integr. Physiol. 208, 70–79.
Significant association of cyp19a promoter methylation with environmental factors and gonadal differentiation in olive flounder Paralichthys olivaceus.Crossref | GoogleScholarGoogle Scholar | 28219743PubMed |

Fleming, N. I., Knower, K. C., Lazarus, K. A., Fuller, P. J., Simpson, E. R., and Clyne, C. D. (2010). Aromatase is a direct target of FOXL2: C134W in granulosa cell tumors via a single highly conserved binding site in the ovarian specific promoter. PLoS One 5, e14389.
Aromatase is a direct target of FOXL2: C134W in granulosa cell tumors via a single highly conserved binding site in the ovarian specific promoter.Crossref | GoogleScholarGoogle Scholar | 21188138PubMed |

Gennotte, V., Mélard, C., D’Cotta, H., Baroiller, J. F., and Rougeot, C. (2014). The sensitive period for male-to-female sex reversal begins at the embryonic stage in the Nile tilapia and is associated with the sexual genotype. Mol. Reprod. Dev. 81, 1146–1158.
The sensitive period for male-to-female sex reversal begins at the embryonic stage in the Nile tilapia and is associated with the sexual genotype.Crossref | GoogleScholarGoogle Scholar | 25482380PubMed |

Guiguen, Y., Fostier, A., Piferrer, F., and Chang, C. F. (2010). Ovarian aromatase and estrogens: a pivotal role for gonadal sex differentiation and sex change in fish. Gen. Comp. Endocrinol. 165, 352–366.
Ovarian aromatase and estrogens: a pivotal role for gonadal sex differentiation and sex change in fish.Crossref | GoogleScholarGoogle Scholar | 19289125PubMed |

Hammond, S. A., Nelson, C. J., and Helbing, C. C. (2016). Environmental influences on the epigenomes of herpetofauna and fish. Biochem. Cell Biol. 94, 95–100.
Environmental influences on the epigenomes of herpetofauna and fish.Crossref | GoogleScholarGoogle Scholar | 26794843PubMed |

Huang, W., Zhou, L., Li, Z., and Gui, J. F. (2009). Expression pattern, cellular localization and promoter activity analysis of ovarian aromatase (Cyp19a1a) in protogynous hermaphrodite red-spotted grouper. Mol. Cell. Endocrinol. 307, 224–236.
Expression pattern, cellular localization and promoter activity analysis of ovarian aromatase (Cyp19a1a) in protogynous hermaphrodite red-spotted grouper.Crossref | GoogleScholarGoogle Scholar | 19443102PubMed |

Kanda, H., Okubo, T., Omori, N., Niihara, H., Matsumoto, N., Yamada, K., Yoshimoto, S., Ito, M., Yamashita, S., Shiba, T., and Takamatsu, N. (2006). Transcriptional regulation of the rainbow trout CYP19a gene by FTZ-F1 homologue. J. Steroid Biochem. Mol. Biol. 99, 85–92.
Transcriptional regulation of the rainbow trout CYP19a gene by FTZ-F1 homologue.Crossref | GoogleScholarGoogle Scholar | 16621513PubMed |

Kikuchi, K., and Hamaguchi, S. (2013). Novel sex-determining genes in fish and sex chromosome evolution. Dev. Dyn. 242, 339–353.
Novel sex-determining genes in fish and sex chromosome evolution.Crossref | GoogleScholarGoogle Scholar | 23335327PubMed |

Kitano, T., Takamune, K., Kobayashi, T. K., Nagahama, Y., and Abe, S. I. (1999). Suppression of P450 aromatase gene expression in sex-reversed males produced by rearing genetically female larvae at a high water temperature during a period of sex differentiation in the Japanese flounder (Paralichthys olivaceus). J. Mol. Endocrinol. 23, 167–176.
Suppression of P450 aromatase gene expression in sex-reversed males produced by rearing genetically female larvae at a high water temperature during a period of sex differentiation in the Japanese flounder (Paralichthys olivaceus).Crossref | GoogleScholarGoogle Scholar | 10514554PubMed |

Li, C. G., Wang, H., Chen, H. J., Zhao, Y., Fu, P. S., and Ji, X. S. (2014). Differential expression analysis of genes involved in high-temperature induced sex differentiation in Nile tilapia. Comp. Biochem. Physiol. B Biochem. Mol. Biol. 177–178, 36–45.
Differential expression analysis of genes involved in high-temperature induced sex differentiation in Nile tilapia.Crossref | GoogleScholarGoogle Scholar | 25199961PubMed |

Lu, H., Zhang, S., Liu, Q., Zhang, L., and Zhang, W. (2014). Cytoplasmic localization of Lrh-1 down-regulates ovarian follicular cyp19a1a expression in a teleost, the orange-spotted grouper Epinephelus coioides. Biol. Reprod. 91, 29.
Cytoplasmic localization of Lrh-1 down-regulates ovarian follicular cyp19a1a expression in a teleost, the orange-spotted grouper Epinephelus coioides.Crossref | GoogleScholarGoogle Scholar | 24943038PubMed |

Mishra, S., and Chaube, R. (2017). Distribution and localization of 3β-hydroxysteroid dehydrogenase (3β-HSD) in the brain and its regions of the catfish Heteropneustes fossilis. Gen. Comp. Endocrinol. 241, 80–88.
Distribution and localization of 3β-hydroxysteroid dehydrogenase (3β-HSD) in the brain and its regions of the catfish Heteropneustes fossilis.Crossref | GoogleScholarGoogle Scholar | 27163792PubMed |

Nakamoto, M., Matsuda, M., Wang, D. S., Nagahama, Y., and Shibata, N. (2006). Molecular 432 cloning and 433 analysis of gonadal expression of Foxl2 in the medaka, Oryzias latipes. Biochem. Bioph. Res. Co. 344, 353–361.
Molecular 432 cloning and 433 analysis of gonadal expression of Foxl2 in the medaka, Oryzias latipes.Crossref | GoogleScholarGoogle Scholar |

Navarro-Martín, L., Viñas, J., Ribas, L., Díaz, N., Gutiérrez, A., Di Croce, L., and Piferrer, F. (2011). DNA methylation of the gonadal aromatase (cyp19a) promoter is involved in temperature-dependent sex ratio shifts in the European sea bass. PLoS Genet. 7, e1002447.
DNA methylation of the gonadal aromatase (cyp19a) promoter is involved in temperature-dependent sex ratio shifts in the European sea bass.Crossref | GoogleScholarGoogle Scholar | 22242011PubMed |

Ospina-Álvarez, N., and Piferrer, F. (2008). Temperature-dependent sex determination in fish revisited: prevalence, a single sex ratio response pattern, and possible effects of climate change. PLoS One 3, e2837.
Temperature-dependent sex determination in fish revisited: prevalence, a single sex ratio response pattern, and possible effects of climate change.Crossref | GoogleScholarGoogle Scholar | 18665231PubMed |

Ottolenghi, C., Omari, S., Garcia-Ortiz, J. E., Uda, M., Crisponi, L., Forabosco, A., Pilia, G., and Schlessinger, D. (2005). Foxl2 is required for commitment to ovary differentiation. Hum. Mol. Genet. 14, 2053–2062.
Foxl2 is required for commitment to ovary differentiation.Crossref | GoogleScholarGoogle Scholar | 15944199PubMed |

Pan, Q., Anderson, J., Bertho, S., Herpin, A., Wilson, C., Postlethwait, J. H., Schartl, M., and Guiguen, Y. (2016). Vertebrate sex-determining genes play musical chairs. C. R. Biol. 339, 258–262.
Vertebrate sex-determining genes play musical chairs.Crossref | GoogleScholarGoogle Scholar | 27291506PubMed |

Pannetier, M., Fabre, S., Batista, F., Kocer, A., Renault, L., Jolivet, G., Mandon-Pépin, B., Cotinot, C., Veitia, R., and Pailhoux, E. (2006). FOXL2 activates P450 aromatase gene transcription: towards a better characterization of the early steps of mammalian ovarian development. J. Mol. Endocrinol. 36, 399–413.
FOXL2 activates P450 aromatase gene transcription: towards a better characterization of the early steps of mammalian ovarian development.Crossref | GoogleScholarGoogle Scholar | 16720712PubMed |

Peng, L., Zheng, Y., You, F., Wu, Z., Zou, Y., and Zhang, P. (2016). Establishment and characterization of a testicular Sertoli cell line from olive flounder Paralichthys olivaceus. Chin. J. Ocean. Limnol. 34, 1054–1063.
Establishment and characterization of a testicular Sertoli cell line from olive flounder Paralichthys olivaceus.Crossref | GoogleScholarGoogle Scholar |

Pérez, M. R., Fernandino, J. I., Carriquiriborde, P., and Somoza, G. M. (2012). Feminization and altered gonadal gene expression profile by ethinylestradiol exposure to pejerrey, Odontesthes bonariensis, a South American teleost fish. Environ. Toxicol. Chem. 31, 941–946.
Feminization and altered gonadal gene expression profile by ethinylestradiol exposure to pejerrey, Odontesthes bonariensis, a South American teleost fish.Crossref | GoogleScholarGoogle Scholar | 22388882PubMed |

Sandra, G. E., and Norma, M. M. (2010). Sexual determination and differentiation in teleost fish. Rev. Fish Biol. Fish. 20, 101–121.
Sexual determination and differentiation in teleost fish.Crossref | GoogleScholarGoogle Scholar |

Schmidt, D., Ovitt, C. E., Anlag, K., Fehsenfeld, S., Gredsted, L., Treier, A. C., and Treier, M. (2004). The murine winged-helix transcription factor Foxl2 is required for granulosa cell differentiation and ovary maintenance. Development 131, 933–942.
The murine winged-helix transcription factor Foxl2 is required for granulosa cell differentiation and ovary maintenance.Crossref | GoogleScholarGoogle Scholar | 14736745PubMed |

Shao, C., Bao, B., Xie, Z., Chen, X., Li, B., Jia, X., Yao, Q., Ortí, G., Li, W., Li, X., et al. (2017). The genome and transcriptome of Japanese flounder provide insights into flatfish asymmetry. Nat. Genet. 49, 119–124.
The genome and transcriptome of Japanese flounder provide insights into flatfish asymmetry.Crossref | GoogleScholarGoogle Scholar | 27918537PubMed |

Shen, Z. G., and Wang, H. P. (2014). Molecular players involved in temperature-dependent sex determination and sex differentiation in teleost fish. Genet. Sel. Evol. 46, 26.
Molecular players involved in temperature-dependent sex determination and sex differentiation in teleost fish.Crossref | GoogleScholarGoogle Scholar | 24735220PubMed |

Shi, H., Gao, T., Liu, Z., Sun, L., Jiang, X., Chen, L., and Wang, D. (2017). Blockage of androgen and administration of estrogen induce transdifferentiation of testis into ovary. J. Endocrinol. 233, 65–80.
Blockage of androgen and administration of estrogen induce transdifferentiation of testis into ovary.Crossref | GoogleScholarGoogle Scholar | 28148717PubMed |

Si, Y., Ding, Y., He, F., Wen, H., Li, J., Zhao, J., and Huang, Z. (2016). DNA methylation level of cyp19a1a and foxl2 gene related to their expression patterns and reproduction traits during ovary development stages of Japanese flounder (Paralichthys olivaceus). Gene 575, 321–330.
DNA methylation level of cyp19a1a and foxl2 gene related to their expression patterns and reproduction traits during ovary development stages of Japanese flounder (Paralichthys olivaceus).Crossref | GoogleScholarGoogle Scholar | 26343797PubMed |

Sun, P., You, F., Zhang, L. J., Wen, A. Y., Wu, Z. H., Xu, D. D., Li, J., and Zhang, P. J. (2009). Histological evaluation of gonadal differentiation in olive flounder (Paralichthys olivaceus). Mark. Sci. 3, 53–58.

Sun, P., You, F., Liu, M., Wu, Z., Wen, A., Li, J., Xu, Y., and Zhang, P. (2010). Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus (Teleostei). Chin. J. Ocean. Limnol. 28, 254–259.
Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus (Teleostei).Crossref | GoogleScholarGoogle Scholar |

Sun, P., You, F., Ma, D., Li, J. P., and Zhang, P. (2013). Sex steroid changes during temperature-induced gonadal differentiation in Paralichthys olivaceus. J. Appl. Ichthyol. 29, 886–890.
Sex steroid changes during temperature-induced gonadal differentiation in Paralichthys olivaceus.Crossref | GoogleScholarGoogle Scholar |

Uhlenhaut, N. H., Jakob, S., Anlag, K., Eisenberger, T., Sekido, R., Kress, J., Treier, A. C., Klugmann, C., Klasen, C., Holter, N. I., Riethmacher, D., Schütz, G., Cooney, A. J., Lovell-Badge, R., and Treier, M. (2009). Somatic sex reprogramming of adult ovaries to testes by FOXL2 ablation. Cell 139, 1130–1142.
Somatic sex reprogramming of adult ovaries to testes by FOXL2 ablation.Crossref | GoogleScholarGoogle Scholar | 20005806PubMed |

Vernetti, C. H., Rodrigues, M., Gutierrez, H. J., Calabuig, C. P., Moreira, C. G., Nlewadim, A., and Moreira, H. L. (2013). Genes involved in sex determination and the influence of temperature during the sexual differentiation process in fish: a review. Afr. J. Biotechnol. 12, 2129–2146.
Genes involved in sex determination and the influence of temperature during the sexual differentiation process in fish: a review.Crossref | GoogleScholarGoogle Scholar |

Vizziano-Cantonnet, D., Baron, D., Mahe, S., Cauty, C., Fostier, A., and Guiguen, Y. (2008). Estrogen treatment up-regulates female genes but does not suppress all early testicular markers during rainbow trout male-to-female gonadal transdifferentiation. J. Mol. Endocrinol. 41, 277–288.
Estrogen treatment up-regulates female genes but does not suppress all early testicular markers during rainbow trout male-to-female gonadal transdifferentiation.Crossref | GoogleScholarGoogle Scholar | 18719050PubMed |

Wang, D. S., Kobayashi, T., Zhou, L. Y., Paul-Prasanth, B., Ijiri, S., Sakai, F., Okubo, K., Morohashi, K., and Nagahama, Y. (2007). Foxl2 up-regulates aromatase gene transcription in a female-specific manner by binding to the promoter as well as interacting with ad4 binding protein/steroidogenic factor 1. Mol. Endocrinol. 21, 712–725.
Foxl2 up-regulates aromatase gene transcription in a female-specific manner by binding to the promoter as well as interacting with ad4 binding protein/steroidogenic factor 1.Crossref | GoogleScholarGoogle Scholar | 17192407PubMed |

Wang, D. S., Zhou, L. Y., Kobayashi, T., Matsuda, M., Shibata, Y., Sakai, F., and Nagahama, Y. (2010). Doublesex- and Mab-3-related transcription factor-1 repression of aromatase transcription, a possible mechanism favoring the male pathway in tilapia. Endocrinology 151, 1331–1340.
Doublesex- and Mab-3-related transcription factor-1 repression of aromatase transcription, a possible mechanism favoring the male pathway in tilapia.Crossref | GoogleScholarGoogle Scholar | 20056824PubMed |

Wang, X. Y., Liu, Q. H., Xiao, Y. S., Yang, Y., Wang, Y. F., Song, Z. C., You, F., An, H., and Li, J. (2017). High temperature causes masculinization of genetically female olive flounder (Paralichthys olivaceus) accompanied by primordial germ cell proliferation detention. Aquaculture 479, 808–816.
High temperature causes masculinization of genetically female olive flounder (Paralichthys olivaceus) accompanied by primordial germ cell proliferation detention.Crossref | GoogleScholarGoogle Scholar |

Wen, A. Y., You, F., Sun, P., Xu, D. D., Wu, Z. H., Ma, D. Y., Li, J., and Zhang, P. J. (2011). Study on cloning and expression of gene sox9 in olive flounder (Paralichthys olivaceus). Adv. Mar. Sci 29, 97–104.
Study on cloning and expression of gene sox9 in olive flounder (Paralichthys olivaceus).Crossref | GoogleScholarGoogle Scholar |

Wen, A. Y., You, F., Sun, P., Li, J., Xu, D. D., Wu, Z. H., Ma, D. Y., and Zhang, P. J. (2014). CpG methylation of dmrt1 and cyp19a promoters in relation to their sexual dimorphic expression in the Japanese flounder Paralichthys olivaceus. J. Fish Biol. 84, 193–205.
CpG methylation of dmrt1 and cyp19a promoters in relation to their sexual dimorphic expression in the Japanese flounder Paralichthys olivaceus.Crossref | GoogleScholarGoogle Scholar | 24372528PubMed |

Wen, A., You, F., Sun, P., Li, J., Xu, D., Wu, Z., Ma, D., Zou, Y., Tan, X., Fan, Z., and Zhang, P. (2015). Sexually dimorphic gene expression patterns during gonadal differentiation in olive flounder, Paralichthys olivaceus Anim. Biol. Leiden Neth. 65, 193–207.
Sexually dimorphic gene expression patterns during gonadal differentiation in olive flounder, Paralichthys olivaceusCrossref | GoogleScholarGoogle Scholar |

Yamaguchi, T., Yamaguchi, S., Hirai, T., and Kitano, T. (2007). Follicle-stimulating hormone signaling and Foxl2 are involved in transcriptional regulation of aromatase gene during gonadal sex differentiation in Japanese flounder, Paralichthys olivaceus. Biochem. Biophys. Res. Commun. 359, 935–940.
Follicle-stimulating hormone signaling and Foxl2 are involved in transcriptional regulation of aromatase gene during gonadal sex differentiation in Japanese flounder, Paralichthys olivaceus.Crossref | GoogleScholarGoogle Scholar | 17574208PubMed |

Yamamoto, E. (1999). Studies on sex-manipulation and production of cloned populations in hirame, Paralichthys olivaceus (Temminck et Schlegel). Aquaculture 173, 235–246.
Studies on sex-manipulation and production of cloned populations in hirame, Paralichthys olivaceus (Temminck et Schlegel).Crossref | GoogleScholarGoogle Scholar |

Yang, Y. J., Wang, Y., Li, Z., Zhou, L., and Gui, J. F. (2017). Sequential, divergent and cooperative requirements of Foxl2a and Foxl2b in ovary development and maintenance of zebrafish. Genetics 205, 1551–1572.
Sequential, divergent and cooperative requirements of Foxl2a and Foxl2b in ovary development and maintenance of zebrafish.Crossref | GoogleScholarGoogle Scholar | 28193729PubMed |

You, F., Liu, J., Wang, X., Xu, Y., Huang, R., and Zhang, P. (2001). Study on embryonic development and early growth of triploid and gynogenetic diploid left-eyed flounder, Paralichthys olivaceus (T. et S.). Chin. J. Ocean. Limnol. 19, 147–151.
Study on embryonic development and early growth of triploid and gynogenetic diploid left-eyed flounder, Paralichthys olivaceus (T. et S.).Crossref | GoogleScholarGoogle Scholar |

Zhang, Y., Zhang, S., Liu, Z., Zhang, L., and Zhang, W. (2013). Epigenetic modifications during sex change repress gonadotropin stimulation of cyp19a1a in a teleost ricefield eel (Monopterus albus). Endocrinology 154, 2881–2890.
Epigenetic modifications during sex change repress gonadotropin stimulation of cyp19a1a in a teleost ricefield eel (Monopterus albus).Crossref | GoogleScholarGoogle Scholar | 23744638PubMed |

Zheng, W. J., and Sun, L. (2011). Evaluation of housekeeping genes as references for quantitative real time RT-PCR analysis of gene expression in Japanese flounder (Paralichthys olivaceus). Fish Shellfish Immunol. 30, 638–645.
Evaluation of housekeeping genes as references for quantitative real time RT-PCR analysis of gene expression in Japanese flounder (Paralichthys olivaceus).Crossref | GoogleScholarGoogle Scholar | 21185941PubMed |