Análise de genes parálogos do hormônio liberador de gonadotrofinas (GnRH) e seu receptor (GnRHR), envolvidos no processo reprodutivo do tambaqui Colossoma macropomum

Abstract

The gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor genes are the most common molecular signal used by the brain to regulate gonadotropin synthesis, plays an important role in almost all vertebrates reproduction. The tambaqui showed three parallel lines of GnRH (cmgnrh1, cmgnrh2 and cmgnrh3) and your receptor GnRHR (cmgnrhr1c, cmgnrhr1ca and cmgnrhr2b), wherein the three binders genes encoding the forms sbGnRH, cGnRH-II and sGnRH. Analysis with gonadal transcripts of the cmgnrh3 gene (sGnRH) reveal a frameshift-like mutation, originating a premature stop codon at the beginning of exon2, which contains the information for the production of the sGnRH peptide. Despite this fact indicating a possible pseudogenization, the gene exhibits high levels of transcription in the olfactory bulb of males and females, presenting differentiated expression in ovaries at the beginning of puberty (data not yet published), suggesting a likely functional role to be investigated, whereas no study so far has analyzed the functioning of this system in the Colossoma macropomum species. Keywords: Colossoma macropomum; Tambaqui; GnRH; frameshift.