Kisspeptin-10 is a ten-amino-acid peptide, the shortest active fragment produced from the KISS1 gene product, that binds and activates the G-protein-coupled receptor GPR54 (now called KISS1R). In the research literature, kisspeptin-10 is studied primarily for its position upstream of gonadotropin-releasing hormone (GnRH) neurons, where it has been examined as a regulator of the pulse generator that governs the hypothalamic-pituitary-gonadal axis. The peptide's history is unusual: the parent gene was first characterized as a tumor metastasis suppressor, years before its receptor or its role in reproductive endocrinology were identified.
Kisspeptin-10 at a glance
| Attribute | Detail |
|---|---|
| Name | Kisspeptin-10 (KP-10), the C-terminal decapeptide of the KISS1 gene product |
| Class | RF-amide neuropeptide; agonist of GPR54/KISS1R |
| Sequence length | 10 amino acids (the minimal fragment reported to retain receptor activity) |
| Origin | Proteolytic cleavage product of the KISS1 precursor, first purified from placental tissue and named metastin |
| What studies examine | GPR54/KISS1R binding, GnRH pulse generator activity, gonadotropin (LH, FSH) secretion in rodent and human research |
| Form supplied | Lyophilized powder for laboratory reconstitution |
Why was kisspeptin first called "metastin"?
The KISS1 gene entered the literature through cancer research, not endocrinology. Lee and Welch transfected the KISS1 gene into human MDA-MB-435 breast carcinoma cells and reported that the modified cells showed suppressed metastatic spread relative to controls, establishing KISS1 as a metastasis-suppressor gene (Lee and Welch, 1997). The gene's protein product was not identified for several more years. In 2001, Ohtaki and colleagues purified the endogenous peptide ligand of an orphan G-protein-coupled receptor from human placental extracts, showed it was encoded by KISS1, and named the peptide metastin after the gene's original metastasis-suppressor function (Ohtaki et al., 2001). Metastin corresponds to what is now called kisspeptin-54, the longest peptide in the family.
What is the kisspeptin family, and what is the RF-amide motif?
The KISS1 precursor protein is proteolytically processed into a set of related peptides that differ in length but share the same carboxy-terminal sequence. Kotani and colleagues characterized this family and showed that kisspeptin-54, kisspeptin-14, kisspeptin-13, and kisspeptin-10 all retain the same ten-residue C-terminal core, ending in an amidated Arg-Phe sequence, an "RF-amide" motif common to a broader class of signaling peptides (Kotani et al., 2001). That same study reported that this shared decapeptide core, kisspeptin-10, is the minimal fragment needed to bind and activate the receptor GPR54, which is why kisspeptin-10 is the form most often used in receptor-binding and pulse-generator studies.
How the four kisspeptin fragments compare
| Peptide | Length | Other name | Reported by |
|---|---|---|---|
| Kisspeptin-54 | 54 amino acids | Metastin | Ohtaki et al., 2001 |
| Kisspeptin-14 | 14 amino acids | None | Kotani et al., 2001 |
| Kisspeptin-13 | 13 amino acids | None | Kotani et al., 2001 |
| Kisspeptin-10 | 10 amino acids | KP-10 | Kotani et al., 2001; George et al., 2011 |
All four share the same C-terminal RF-amide sequence, which is the segment the receptor recognizes. This is why studies frequently substitute the shorter, more synthesis-friendly kisspeptin-10 for the full-length metastin peptide when probing receptor pharmacology.
How does GPR54/KISS1R connect kisspeptin to the GnRH pulse generator?
GPR54 was an orphan receptor, meaning its natural ligand was unknown, until Ohtaki and colleagues identified kisspeptin as that ligand in 2001. Its role in reproduction was established two years later. Seminara and colleagues reported that loss-of-function mutations in GPR54 were found in patients with idiopathic hypogonadotropic hypogonadism, a failure to enter puberty linked to absent or blunted GnRH secretion, and that Gpr54-deficient mice showed a parallel reproductive phenotype (Seminara et al., 2003). Because GnRH neurons themselves were not found to express appreciable kisspeptin, the receptor was placed upstream of GnRH neurons, in a signaling relay rather than as GnRH's own autoreceptor. Following the discovery that kisspeptins are its endogenous ligands, the receptor was subsequently renamed KISS1R in later literature, and its gene product is catalogued under that name (UniProt, KISS1_HUMAN entry).
What have animal and human studies examined?
Once GPR54/KISS1R was linked to the reproductive axis, researchers began administering kisspeptin peptides in controlled studies to characterize the pathway further, primarily by measuring luteinizing hormone (LH) and follicle-stimulating hormone (FSH) as downstream readouts of GnRH pulse generator activity.
Dhillo and colleagues administered kisspeptin-54 intravenously to healthy adult men in a clinical research setting and reported increases in circulating LH, FSH, and testosterone during the infusion period, supporting kisspeptin's position upstream of the hypothalamic-pituitary-gonadal axis (Dhillo et al., 2005).
Kisspeptin-10 specifically has been examined in frequent-sampling human studies designed to resolve pulsatile hormone release. George and colleagues administered kisspeptin-10 intravenously to healthy men and reported that it stimulated LH release and increased LH pulse frequency, a study design used to probe the peptide's action on the GnRH pulse generator directly rather than on single-timepoint hormone levels (George et al., 2011). A separate clinical study extended this line of investigation to repeated subcutaneous administration of kisspeptin-10 over a multi-day study period in healthy men, with gonadotropin secretion tracked as the outcome measure across the study window (Yeung et al., 2026). Across this literature, kisspeptin-10 is consistently used as a pharmacological probe of receptor and pulse generator function rather than as a studied therapeutic in its own right, and none of these compounds is an approved medicine.
How is kisspeptin-10 supplied and handled in the lab?
Our kisspeptin-10 listing ships as a lyophilized (freeze-dried) powder, the standard form for small peptides because it is far more stable in storage and transit than a peptide already in solution. Our explainer on lyophilization covers why freeze-drying is used and what it does and does not protect against. Before use in an assay, the lyophilized powder is reconstituted with an appropriate diluent and brought to a known concentration; the arithmetic for that step, including how vial mass, diluent volume, and target concentration relate to each other, is covered in our reconstitution math guide, and our bacteriostatic water listing is one commonly used diluent for bench reconstitution. Because kisspeptin-10 is a short peptide with an amidated C-terminus, standard peptide handling practices apply: minimize freeze-thaw cycles once reconstituted, keep solutions cold and shielded from light where possible, and use aliquots suited to a single experiment rather than repeated withdrawals from one vial. General background on peptide structure and stability is available in our overview of peptide structure and in the kisspeptin-10 research library monograph, which tracks the compound's specification and literature separately from this article.
Frequently asked questions
Is kisspeptin-10 the same molecule as metastin?
No. Metastin is the name given to kisspeptin-54, the full-length 54-amino-acid peptide originally purified from placental tissue (Ohtaki et al., 2001). Kisspeptin-10 is the shorter, ten-amino-acid C-terminal fragment shared by all members of the kisspeptin family. Kotani and colleagues reported that this shared decapeptide core is sufficient to bind and activate GPR54, which is why kisspeptin-10 rather than the full metastin sequence is the form most used in receptor studies (Kotani et al., 2001).
What does the RF-amide motif mean?
RF-amide refers to a C-terminal Arg-Phe sequence with an amide group in place of the usual free carboxylic acid. Kotani and colleagues identified this amidated motif as the shared feature across kisspeptin-54, -14, -13, and -10, and reported it as necessary for receptor binding (Kotani et al., 2001). RF-amide peptides are a broader structural class found across several signaling systems, not unique to kisspeptin.
Is GPR54 the same receptor as KISS1R?
Yes. GPR54 was the receptor's designation while it was still an orphan receptor with no known ligand. After Ohtaki and colleagues identified kisspeptin as its endogenous ligand, and after Seminara and colleagues linked the receptor to human reproductive development, the literature and gene databases adopted the name KISS1R to reflect the KISS1-derived ligand (Ohtaki et al., 2001; Seminara et al., 2003; UniProt KISS1_HUMAN entry).
What role does kisspeptin-10 play in GnRH regulation, according to the literature?
Published studies place kisspeptin-10 upstream of GnRH neurons rather than acting as GnRH itself. Loss-of-function GPR54/KISS1R mutations were associated with failure to enter puberty in humans and a parallel phenotype in mice (Seminara et al., 2003), and intravenous kisspeptin-10 was reported to increase LH pulse frequency in men, a marker of increased GnRH pulse generator activity (George et al., 2011). These findings are reported as a signaling relationship studied in specific experimental models, not as a clinical outcome.
Has kisspeptin-10 been approved as a medicine?
No. Kisspeptin-10 has been used in clinical research settings as an investigational infusion to study the reproductive axis (Dhillo et al., 2005; George et al., 2011; Yeung et al., 2026), but it is not an FDA-approved drug and has no approved indication. Homegrown Peptides sells kisspeptin-10 as a research chemical for laboratory use only; it is not manufactured, tested, or labeled for human or animal administration.
Why does the KISS1 gene keep showing up in both cancer and reproductive biology literature?
The gene was discovered first in metastasis research, where its transfection into breast carcinoma cells was reported to suppress metastatic spread (Lee and Welch, 1997). Its peptide product and receptor were not identified until 2001, and the reproductive axis role was only established in 2003 (Ohtaki et al., 2001; Seminara et al., 2003). Both lines of research continue in parallel because the same gene product and receptor pair are studied in each context, though the mechanisms examined differ by field.
References
- Lee JH, Welch DR. Suppression of metastasis in human breast carcinoma MDA-MB-435 cells after transfection with the metastasis suppressor gene, KiSS-1. Cancer Research. 1997. https://pubmed.ncbi.nlm.nih.gov/9192814/
- Ohtaki T, Shintani Y, Honda S, et al. Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor. Nature. 2001. https://pubmed.ncbi.nlm.nih.gov/11385580/
- Kotani M, Detheux M, Vandenbogaerde A, et al. The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54. Journal of Biological Chemistry. 2001. https://pubmed.ncbi.nlm.nih.gov/11457843/
- Seminara SB, Messager S, Chatzidaki EE, et al. The GPR54 gene as a regulator of puberty. New England Journal of Medicine. 2003. https://pubmed.ncbi.nlm.nih.gov/14573733/
- Dhillo WS, Chaudhri OB, Patterson M, et al. Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males. Journal of Clinical Endocrinology and Metabolism. 2005. https://pubmed.ncbi.nlm.nih.gov/16174713/
- George JT, Veldhuis JD, Roseweir AK, et al. Kisspeptin-10 is a potent stimulator of LH and increases pulse frequency in men. Journal of Clinical Endocrinology and Metabolism. 2011. https://pubmed.ncbi.nlm.nih.gov/21632807/
- Yeung AC, Phylactou M, Koysombat K, et al. Chronic subcutaneous kisspeptin-10 stimulates gonadotropin secretion for 12 days in healthy men. European Journal of Endocrinology. 2026. https://pubmed.ncbi.nlm.nih.gov/42549827/
- UniProt Consortium. KISS1_HUMAN (Q15726): Metastasis-suppressor KiSS-1 (Kisspeptin-1). https://www.uniprot.org/uniprotkb/Q15726/entry
Research use only. Homegrown Peptides products are for laboratory research and are not for human or animal use. Nothing in this article is medical advice.
