The KiSS1-derived peptide receptor (also known as GPR54 or the Kisspeptin receptor) is a Gq-coupled receptor which binds the peptide hormone kisspeptin (metastin). The KiSS1 gene inhibits metastatic activity of melanoma and other tumor cell lines, and clinical evidence supports a role for KiSS1 in inhibition of metastasis in human cancer. Kisspeptins and GPR54 also play a central role in hypothalamic regulation of puberty, by directly governing the release of gonadotropin-releasing hormone from the hypothalamus. In addition, mutations in GPR54 in mice and humans result in hypogonadotropic hypogonadism.