title: Gonadotropin subunits of the characiform Astyanax altiparanae: Molecular characterization, spatiotemporal expression and their possible role on female reproductive dysfunction in captivity.
abstract: To better understand the endocrine control of reproduction in Characiformes and the reproductive dysfunctions that commonly occur in migratory fish of this order when kept in captivity, we chose Astyanax altiparanae, which has asynchronous ovarian development and multiple spawning events, as model species. From A. altiparanae pituitary total RNA, we cloned the full-length cDNAs coding for the follicle-stimulating hormone β subunit (fshb), the luteinizing hormone β subunit (lhb), and the common gonadotropin α subunit (gpha). All three sequences showed the highest degree of amino acid identity with other homologous sequences from Siluriformes and Cypriniformes. Real-time, quantitative PCR analysis showed that gpha, fshb and lhb mRNAs were restricted to the pituitary gland. In situ hybridization and immunofluorescence, using specific-developed and characterized polyclonal antibodies, revealed that both gonadotropin β subunits mRNAs/proteins are expressed by distinct populations of gonadotropic cells in the proximal pars distalis. No marked variations for lhb transcripts levels were detected during the reproductive cycle, and 17α,20β-dihydroxy-4-pregnen-3-one plasma levels were also constant, suggesting that the reproductive dysfunction seen in A. altiparanae females in captivity are probably due to a lack of increase of Lh synthesis during spawning season. In contrast, fshb transcripts changed significantly during the reproductive cycle, although estradiol-17β (E2) levels remained constant during the experiment, possibly due to a differential regulation of E2synthesis. Taken together, these data demonstrate the putative involvement of gonadotropin signaling on the impairment of the reproductive function in a migratory species when kept in captivity. Future experimental studies must be carried to clarify this hypothesis. All these data open the possibility for further basic and applied studies related to reproduction in this fish model.
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Lázaro Wender O
authors.initials: LWO
authors.lastname: de Jesus
authors.affiliation: Reproductive Biology Group, Division Developmental Biology, Department of Biology, Faculty of Sciences, Utrecht University, Hugo R. Kruyt Building, Padualaan 8, 3584 CH Utrecht, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Bogerd
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Felipe M
authors.initials: FM
authors.lastname: Vieceli
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Giovana S
authors.initials: GS
authors.lastname: Branco
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Marília P
authors.initials: MP
authors.lastname: Camargo
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Mônica
authors.initials: M
authors.lastname: Cassel
authors.affiliation: Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, n.321, 05508-090 São Paulo, SP, Brazil.
authors.forename: Renata G
authors.initials: RG
authors.lastname: Moreira
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil.
authors.forename: Chao Y I
authors.initials: CYI
authors.lastname: Yan
authors.affiliation: Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Professor Lineu Prestes 1524, 05508-000 São Paulo, SP, Brazil. Electronic address: miborell@usp.br.
authors.forename: Maria I
authors.initials: MI
authors.lastname: Borella
mesh_terms: D000818:Animals; D015153:Blotting, Western; D060126:Characidae / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D004958:Estradiol / Q000097:blood*; D005260:Female; D037201:Follicle Stimulating Hormone, beta Subunit / Q000235:genetics / Q000378:metabolism*; D052681:Gonadotrophs / Q000378:metabolism; D007103:Immobilization; D007124:Immunoenzyme Techniques; D007247:Infertility, Female / Q000503:physiopathology*; D037101:Luteinizing Hormone, beta Subunit / Q000235:genetics / Q000378:metabolism*; D010902:Pituitary Gland / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012098:Reproduction / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D018076:DNA, Complementary; D037201:Follicle Stimulating Hormone, beta Subunit; D037101:Luteinizing Hormone, beta Subunit; D012333:RNA, Messenger; D004958:Estradiol
keywords: Characiformes; Gonadotropic cells; Molecular cloning; Ovary; Pituitary gland; Steroidogenesis