title: Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus).
abstract: Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120 dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90 dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish.
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China.
authors.forename: Linyan
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China.
authors.forename: Feng
authors.initials: F
authors.lastname: Luo
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Fang
authors.affiliation: South Ehime Fisheries Research Center, Ehime University, Ainan, 798-4206, Japan.
authors.forename: Tapas
authors.initials: T
authors.lastname: Charkraborty
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China.
authors.forename: Limin
authors.initials: L
authors.lastname: Wu
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wei
authors.affiliation: Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, PR China. Electronic address: wdeshou@swu.edu.cn.
authors.forename: Deshou
authors.initials: D
authors.lastname: Wang
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D023681:Cichlids / Q000502:physiology*; D004967:Estrogens / Q000737:chemistry; D005260:Female; D020869:Gene Expression Profiling; D006908:Hydroxyprogesterones / Q000737:chemistry; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D008297:Male; D008540:Meiosis; D015735:Mifepristone / Q000737:chemistry; D008938:Mitosis; D010053:Ovary / Q000166:cytology*; D016133:Polymerase Chain Reaction; D011372:Progestins / Q000502:physiology*; D011980:Receptors, Progesterone / Q000037:antagonists & inhibitors*; D012733:Sex Differentiation; D013091:Spermatogenesis
chemical_list: D004967:Estrogens; D006908:Hydroxyprogesterones; D011372:Progestins; D011980:Receptors, Progesterone; C021012:17 alpha,20 beta-dihydroxypregn-4-en-3-one; D015735:Mifepristone
keywords: DHP; Estrogen; RU486 treatment; Sex reversal; Spermatogenesis