The regenerative peptide FPP: A multi-target discovery from the Ascidian Halocynthia roretzi peptidome

This study identified a novel tissue-regenerative peptide from the marine ascidian Halocynthia roretzi. Optimized enzymatic hydrolysis using a protease produced a hydrolysate from which 3220 peptide sequences were identified by LC-MS/MS. Bioinformatic screening selected 18 non-toxic candidates, and molecular docking against Caspase-3, ERK1, and p38α highlighted three peptides (FPP, FMP, WPG) with strong binding affinities. These peptides originate from elongation factor 1-alpha, tubulin beta chain, and integrin alpha-Hr1, respectively. Among them, FPP exhibited the most promising profile, showing the highest binding energy (-7.42 kcal/mol) for ERK1. In a zebrafish caudal fin amputation model, FPP significantly enhanced tissue regeneration and locomotor function. It also reduced inflammation, promoted collagen deposition, and increased antioxidant capacity (T-AOC: 27.54 U/mg; CAT: 60.37 U/mg). These results establish FPP as a promising functional food ingredient for tissue repair.