Molecular characterization, tissue distribution, and mRNA expression profiles of two Kiss genes in the adult male and female chub mackerel (Scomber japonicus) during different gonadal stages

Kisspeptin and seasonal control of reproduction in male European sea bass (Dicentrarchus labrax)

“…These results came as a surprise given the suggested stimulatory role of kisspeptin on GnRH neurons, through kisspeptin receptors, to initiate puberty [28,74,64]. These profiles of kisspeptin expression contrast with previously published studies performed in zebrafish where both Kiss1 and kiss2 gene expression increased prior or during the early phase of spermatogenesis [4,37] and male chub mackerel where Kiss1 brain expression gradually decreased during spermatogenesis, however there were some similarities in the kiss2 expression profiles as in chub mackerel it increased during the late spermatogenesis stages and declined during spermiation [70]. Overall, similar results to the present findings were found in male and female grass puffer in which brain kiss2 (and its receptor gene) expression peaked during spawning in both males and females [75].…”

Kisspeptin-1 directly stimulates LH and GH secretion from goldfish pituitary cells in a Ca2+-dependent manner

“…In addition, only Kiss1, but not Kiss2, mRNA was detectable in the pituitary of adult male and female chub mackerel and its expression level did not significantly fluctuate over different stages of gonadal development [36]. On the other hand, gKiss2 10 has been shown to stimulate goldfish pituitary LH and GH secretion in another study by Yang and colleagues [46], and Kiss2-, but not Kiss1-, immunoreactive cells are detected in the adenophypohysis of adult zebrafish [37].…”

“…In teleosts including cyprinids, two kisspeptins (Kiss1 and Kiss2) and two kisspeptin receptors (Kiss1R and Kiss2R), as well as Kiss and KissR isoforms, have been indentified [1,12,16,24,25,36,42,43,46]. In Morone bass species, Kiss2R and Kiss1R are differentially expressed by hypothalamic preoptic GnRH neurons and cells attached to GnRH neurons [50].…”

MOLECULAR EVOLUTION OF GPCRS: Kisspeptin/kisspeptin receptors

“…Only the Kiss2 gene is present in some species such as fugu (Takifugu niphobles), tetraodon (Tetraodon nigroviridis), and stickleback (Gasterosteus aculeatus) (Pasquier et al 2012b). In contrast, the Kiss1 and Kiss2 genes have been characterized in some other species including zebrafish (Danio rerio) (Biran et al 2008), goldfish (Carassius auratus) (Li et al 2009), medaka (Oryzias latipes) (Lee et al 2009b), chub mackerel (Scomber japonicus) (Selvaraj et al 2010), striped bass (Morone saxatilis) (Zmora et al 2012), and European eel (Pasquier et al 2012b).…”