title: Expression profiles of gonadotropins and their receptors during 17α-methyltestosterone implantation-induced sex change in the orange-spotted grouper (Epinephelus coioides).
abstract: It is known that the hypothalamic-pituitary-gonadal axis participates in the sex change of hermaphrodite teleosts, and gonadal steroid hormones mediate this physiological process. The secretion of gonadal steroids is directly regulated by signaling pathways involving gonadotropins (GtHs) and gonadotropin receptors (GtHRs) in teleosts. To gain insight into the involvement of GtH/GtHR systems in the sex change process, cDNAs encoding follicle-stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHR) were firstly isolated from gonads of orange-spotted grouper (Epinephelus coioides), a protogynous hermaphrodite fish. Reverse transcription-PCR (RT-PCR) analysis demonstrated that the expression of the FSHR was confined to the brain, pituitary gland, ovary, and testis, while the LHR was expressed only in the brain, ovary, and testis. Furthermore, the expression profiles of GtH subunits (FSHβ and LHβ) and their receptors were analyzed in parallel with the serum levels of estradiol-17β (E(2) ), testosterone (T), and 11-ketotestosterone (11-KT) during 17α-methyltestosterone (MT)-induced sex change. Quantitative real-time PCR determined that the abundances of FSHβ and FSHR were significantly inhibited after MT treatment for 2 and 4 weeks, but subsequently returned to the control level after 6 weeks. In contrast, the mRNA levels of LHβ and LHR were significantly elevated throughout the sex change process. During MT-induced sex change, serum concentrations of E(2) remained constant while T and 11-KT levels were significantly increased. Taken together, our results suggest that GtH/GtHR systems are involved in MT-induced sex change, and two signaling pathways may have distinct roles in modulating the variations of the corresponding steroid hormones in the orange-spotted grouper.
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Xuesong
authors.initials: X
authors.lastname: Hu
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Liu
authors.forename: Haifa
authors.initials: H
authors.lastname: Zhang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shuisheng
authors.initials: S
authors.lastname: Li
authors.forename: Qing
authors.initials: Q
authors.lastname: Sang
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Wenna
authors.initials: W
authors.lastname: Luo
authors.forename: Qizhi
authors.initials: Q
authors.lastname: Liu
authors.forename: Danqi
authors.initials: D
authors.lastname: Lu
authors.forename: Zining
authors.initials: Z
authors.lastname: Meng
authors.forename: Haoran
authors.initials: H
authors.lastname: Lin
mesh_terms: D000818:Animals; D001492:Bass / Q000235:genetics / Q000378:metabolism; D004958:Estradiol / Q000097:blood; D005260:Female; D037201:Follicle Stimulating Hormone, beta Subunit / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D057850:Hermaphroditic Organisms / Q000235:genetics / Q000378:metabolism; D037101:Luteinizing Hormone, beta Subunit / Q000819:agonists / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008777:Methyltestosterone / Q000494:pharmacology*; D010053:Ovary / Q000187:drug effects / Q000378:metabolism; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011962:Receptors, FSH / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011974:Receptors, LH / Q000819:agonists / Q000235:genetics / Q000378:metabolism*; D012727:Sex Characteristics; D019849:Sex Determination Processes; D057829:Gender-Affirming Procedures; D013737:Testis / Q000187:drug effects / Q000378:metabolism; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood; D013997:Time Factors; D014018:Tissue Distribution / Q000235:genetics
chemical_list: D037201:Follicle Stimulating Hormone, beta Subunit; D037101:Luteinizing Hormone, beta Subunit; D012333:RNA, Messenger; D011962:Receptors, FSH; D011974:Receptors, LH; D013739:Testosterone; D004958:Estradiol; C003600:11-ketotestosterone; D008777:Methyltestosterone