Molecular cloning of GnRH of Astyanax altiparanae and its effect in vivo

Abstract

The study on fish reproduction gained importance in last years due the possibility of manipulation of the reproductive process, especially in endangered species. During this process, Kisspeptin regulated hypothalamic neurons produce GnRH, which stimulates the pituitary cells to release FSH and LH, which promote gonadal maturation. The GnRH, beyond the reproductive function, participates of the neuromodulation of sexual behavior. Thus, the knowledge of the specific hypophysiotropic isoform of this molecule for each species can be crucial for efficient reproduction. Currently there are 25 isoforms of GnRH described among vertebrates and invertebrates, two or three of these isoforms normally found in a single species. In addition, the GnRH is considered a marker for studies of evolution, since the genes encoding the GnRH in vertebrates have the same architecture. Thus, we intend to make the molecular cloning of the GnRH of lambari Astyanax altiparanae, a South American species with relevant importance, and, with the injection of the obtained peptide, analyze the proteic expression of LH and the synthesis of gonadal steroids. Finally, it may be an attempt to improve the conditions of spawning in captivity of the same order species (Characiforms), which represents the majority of the cultivated species in Brazil, since most of these animals kept in captivity displays difficulty in reproduce without hormonal induction. So, the research is important in academic area because of the molecular cloning of the GnRH gene in Characiforms, and in ecological and economic area because of the future improvement in the practice of fish farming that the results of this research can bring. (AU)