Kisspeptin-10 (metastin 45-54, KP-10) is the C-terminal decapeptide of the kisspeptins, Tyr-Asn-Trp-Asn-Ser-Phe-Gly-Leu-Arg-Phe-NH2, equivalent to residues 112-121 of the KiSS-1 precursor. The kisspeptins were identified in 2001 as products of KiSS-1, a metastasis suppressor gene, and as the endogenous ligands of the orphan receptor GPR54, now also called KISS1R. Genetic work in 2003 linked GPR54 to the onset of puberty in humans and mice, and kisspeptin-10 has since been used widely as a research probe of the hypothalamic-pituitary-gonadal axis in rodents, sheep and non-human primates.