title: Structural optimization of pep7, a small peptide extracted from epimorphin, for effective induction of hair follicle anagen.
abstract: Epimorphin is representative of a unique class of stromal membrane-anchored proteins that plays distinct functions depending on its membrane topology. When exposed extracellularly, this molecule acts as a morphoregulator for various tissues including hair follicle epithelia. Previous study identified its functional domain (the pep7 domain: SIEQSCDQDE) for hair follicular morphogenesis followed by the successful generation of a chemically modified active peptide. Here, we report optimization of this peptide by the introduction of sequential mutations and subsequent structural determination. We found that three residues from the C-terminus are dispensable, and alternation of the seventh amino acid to an Alanine residue enhanced activity. To favour the biologically active conformation, epsilon-Acp (NH(CH(2))(5)CO) linked to a Cysteine residue was connected at the N-terminus followed by the introduction of an intramolecular disulphide bridge, the modification process of which could be included in the peptide synthesis. The obtained modified peptide, termed 'EPM (epimorphin-derived) peptide', has a Mw of 950 Da and exerts an inductive effect on hair follicle regeneration at a concentration of approximately 0.00001% or even lower. The action of this EPM peptide was more apparent in mice treated with 1% minoxidil, suggesting its potential clinical benefit as a new type of hair-regenerating agent.
authors.affiliation: Department of Morphoregulation, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Hirai
authors.forename: Kyoko
authors.initials: K
authors.lastname: Takebe
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Nakajima
mesh_terms: D000505:Alopecia / Q000188:drug therapy; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D003545:Cysteine / Q000737:chemistry; D004848:Epithelium / Q000378:metabolism; D015723:Gene Library; D018859:Hair Follicle / Q000187:drug effects* / Q000378:metabolism*; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000737:chemistry*; D051379:Mice; D008809:Mice, Inbred C3H; D008969:Molecular Sequence Data; D009154:Mutation; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D050827:Syntaxin 1; D013696:Temperature; D013997:Time Factors
chemical_list: D008562:Membrane Glycoproteins; D010455:Peptides; C074558:STX2 protein, human; D050827:Syntaxin 1; D003545:Cysteine