Molecular cloning and expression of follicle stimulating (FSH) and luteinizing hormones (LH) and profiles of sex steroids during gonadal differentiation and reproductive cycle of the Characiform Astyanax altiparanae

• Grant number: 11/19268-8
• Support type: Scholarships in Brazil - Doctorate
• Effective date (Start): December 01, 2011
• Effective date (End): September 30, 2015
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Aquaculture
• Principal researcher: Maria Ines Borella
• Grantee: Lázaro Wender Oliveira de Jesus
• Home Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 13/18297-0 - Molecular characterization, cellular localization, and gene expression studies of the mRNAs coding for the gonadotropin subunits and the gonadotropin receptors of, and the plasma profiles of three sex steroids in Astyanax altiparanae (Teleostei, Characiformes), BE.EP.DR

Abstract

Reproduction in teleost fish is regulated by the hypothalamus-pituitary-gonads axis (HPG). Under regulation of GnRH, the pituitary gland secrets two gonadotropins: follicle-estimulating (FSH) and luteinising hormones (LH), heterodimers formed by a common alpha subunit, and a beta subunit, which confers specific biological functions. The gonadotropins modulate the production of sex steroids in the gonads, which in turn, act in the maintenance and regulation of the whole reproductive process. The information available about the hormonal regulation of reproduction in the South American teleost exercised by different levels of the HPG are scarce, although they showed the greatest diversity of species on Earth and a range of reproductive strategies. In this project, we propose to investigate the hormonal aspects that regulate the reproductive axis in Astyanax altiparanae Garutti e Britski, 2000, a Characiform endemic species of the Paraná river basin, which shows ecological, economic and academic relevance. Specifically, we aimed to (1) carry out the molecular cloning and phylogenetic analysis of the genes encoding bFSH and bLH from A. altiparanae, (2) analyse the expression profile of these genes using Real-Time qPCR during ontogeny and during the annual reproductive cycle in captivity, (3) its possible expression in other organs beyond the pituitary gland and (4) quantify by ELISA the levels of the sexual steroids during the reproductive cycle, in order to correlate the levels of these hormones with the process of gonadal differentiation and the different stages of the reproductive cycle in males e females of this species. Thus, we intend to elucidate some of the endocrine control of reproduction in this representative Characiform species, and in an indirect way, contribute to the improvement of techniques of induced spawning of native species, a limiting process in fish farming. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE JESUS, LAZARO WENDER O.; BOGERD, JAN; VIECELI, FELIPE M.; BRANCO, GIOVANA S.; CAMARGO, MARILIA P.; CASSEL, MONICA; MOREIRA, RENATA G.; YAN, CHAO Y. I.; BORELLA, MARIA I. Gonadotropin subunits of the characiform Astyanax altiparanae: Molecular characterization, spatiotemporal expression and their possible role on female reproductive dysfunction in captivity. General and Comparative Endocrinology, v. 246, p. 150-163, MAY 15 2017. Web of Science Citations: 4.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

JESUS, Lázaro Wender Oliveira de. Gonadotropins and their receptors in Astyanax altiparanae (Teleostei, Characiformes): molecular characterization and spatio-temporal expression during the reproductive cycle in captivity. 2016. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas São Paulo.