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, Thymosin Beta-4 promotes wound healing, angiogenesis, and tissue regeneration in preclinical models via effects on cytoskeleton dynamics, cell migration, and anti-apoptotic pathways25579.
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, Thymosin Beta-4 is an endogenous 43-amino-acid actin-sequestering peptide that maintains a pool of G-actin monomers and regulates actin polymerization, thereby influencing cell migration, proliferation, and differentiation25579.
Length and Sequence
Melanotan I is 13 amino acids long, whereas Thymosin Beta-4 is longer as it has a length of 43 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. Thymosin Beta-4 is made up of a sequence of Serine, Aspartic acid, Lysine, Proline, Aspartic acid, Methionine, Alanine, Glutamic acid, Isoleucine, Glutamic acid, Lysine, Phenylalanine, Aspartic acid, Lysine, Serine, Lysine, Lysine, Proline, Aspartic acid, Methionine, Alanine, Glutamic acid, Glutamic acid, Lysine, Phenylalanine, Aspartic acid, Lysine, Lysine, Glutamic acid, Lysine, Lysine, Glutamic acid, Glutamic acid, Alanine, Glutamic acid, Asparagine, Glutamic acid, Glutamic acid, Lysine, Glutamic acid, Serine.