Kisspeptin in Nile tilapia O. niloticus: Receptor expression during the onset of puberty and effects of constant illumination
The peptides of the kisspeptin family including Kiss 1 and its cognate G protein-coupled receptor 54 (GPR54) have been shown to be involved in the initiation of puberty in higher vertebrates. Interestingly recent research has suggested that the Kiss1/GPR54 system is a conserved feature also found in teleosts. In the current study, the developmental expression of GPR54 and GnRH I receptor (rGnRH I) in brains was investigated during the onset of puberty in Nile tilapia. Results have shown that GPR54 gene expression increased at around 11 weeks post hatch (WPH) followed by rGnRH I at 13 WPH. First signs of active gametogenesis were seen at 17 WPH, which could suggest a link between GPR54 and the onset of puberty in tilapia. Furthermore, an effect of continuous light was also observed on the expression levels of GPR54.