We just published a new article with Elia Ciani, a PhD student that I am co-supervising, and other members of the team as well as collaborators, in General and Comparative Endocrinology.
The paper is entitled “Gnrh receptor gnrhr2bbα is expressed exclusively in lhb-expressing cells in Atlantic salmon male parr” abd reports the structural, functional and physiological characterization of five high‐affinity melatonin receptors in Atlantic salmon, and their daily fluctuations across seasons.
Gonadotropin-releasing hormone (Gnrh) plays a major role in the regulation of physiological and behavioural processes related to reproduction. In the pituitary, it stimulates gonadotropin (Luteinising hormone, Lh and Follicle-Stimulating hormone, Fsh) synthesis and release via activation of Gnrh receptors (Gnrhr). In teleosts, the roles of the different Gnrhr isoforms still not well understood.
This study investigates the gene expression of Gnrhr in the pituitary gland during sexual maturation in Atlantic salmon (Salmo salar) male parr. Among the six investigated paralogs, one named gnrhr2bbα, was differentially expressed depending on maturational stage, with high expression levels in maturing fish, increasing in parallel with gonadotropin subunit gene expression. Double fluorescence in situ hybridization showed that gnrhr2bbα was expressed exclusively in lhb gonadotropes in the pituitary, with no expression detected in fshb cells. These results suggest the involvement of receptor paralog gnrhr2bbα in the regulation of lhb cells, and not fshb cells, in sexually maturing Atlantic salmon male parr.
Publication in General and Comparative Endocrinology, doi 10.1016/j.ygcen.2019.113293