Comparison

Melanotan I vs Melanotan II

Function

While Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444, Melanotan II is studied as a tanning and libido-enhancing agent; increases melanin production and can reduce food intake and modulate sexual arousal in animal models and humans3545.

Mechanism

While Melanotan I works as a linear 13-amino-acid analog of α-MSH (afamelanotide) that selectively activates MC1R on melanocytes, increasing eumelanin synthesis and providing photoprotection3444, Melanotan II is a cyclic heptapeptide melanocortin analog (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2) that acts as a non-selective, high-potency agonist at MC1R, MC3R, MC4R, and MC5R, influencing pigmentation, appetite, and sexual behavior3545.

Length and Sequence

Melanotan I is 13 amino acids long, whereas Melanotan II is shorter as it has a length of 7 amino acids. Melanotan I is made up of a sequence of Serine, Tyrosine, Serine, Nle, Glutamic acid, Histidine, Phenylalanine, Arginine, Tryptophan, Glycine, Lysine, Proline, Valine. Melanotan II is made up of a sequence of Nle, Aspartic acid, Histidine, Phenylalanine, Arginine, Tryptophan, Lysine.

Receptor

Melanotan I

Melanocortin-1 receptor (MC1R) 344481

Melanotan II

Melanocortin receptors MC1R, MC3R, MC4R, and MC5R (non-selective agonist) 3545

Organism or Origin

Melanotan I

Synthetic analog of human α-MSH derived from POMC34448190

Melanotan II

Synthetic analog of POMC-derived melanocortin peptides358190

Gene

Melanotan I

POMC

Melanotan II

POMC

Related articles

No related articles are linked to these peptides yet.

Sources

34Melanotan I (Afamelanotide): Research Profile - PeptideJournal, https://www.peptidejournal.org/peptides/melanotan-i-research-profile
44Melanotan I: properties, applications and references, https://www.benchchem.com/zh/product/b1666627
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/
35What is melanotan II? - Creative Peptides, https://www.creative-peptides.com/resources/what-is-melanotan-ii-peptide.html
45[PDF] melanotan-II peptide structure and molecular formula - Benchchem, https://www.benchchem.com/pdf/melanotan_II_peptide_structure_and_molecular_formula.pdf
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/