title: A Cyclized Helix-Loop-Helix Peptide as a Molecular Scaffold for the Design of Inhibitors of Intracellular Protein-Protein Interactions by Epitope and Arginine Grafting.
abstract: The design of inhibitors of intracellular protein-protein interactions (PPIs) remains a challenge in chemical biology and drug discovery. We propose a cyclized helix-loop-helix (cHLH) peptide as a scaffold for generating cell-permeable PPI inhibitors through bifunctional grafting: epitope grafting to provide binding activity, and arginine grafting to endow cell-permeability. To inhibit p53-HDM2 interactions, the p53 epitope was grafted onto the C-terminal helix and six Arg residues were grafted onto another helix. The designed peptide cHLHp53-R showed high inhibitory activity for this interaction, and computational analysis suggested a binding mode for HDM2. Confocal microscopy of cells treated with fluorescently labeled cHLHp53-R revealed cell membrane penetration and cytosolic localization. The peptide inhibited the growth of HCT116 and LnCap cancer cells. This strategy of bifunctional grafting onto a well-structured peptide scaffold could facilitate the generation of inhibitors for intracellular PPIs.
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Fujiwara
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Kitada
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Oguri
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Nishihara
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Michigami
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Shiraishi
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Yuba
authors.affiliation: N2RC, Osaka Prefecture University, 1-2, Gakuen-cho, Naka-ku, Osaka, 599-8570, Japan.
authors.forename: Ikuhiko
authors.initials: I
authors.lastname: Nakase
authors.affiliation: Department of Chemistry, Sookmyung Women's University, Hyochangwongil 52, Yongsanku, Seoul, 140-742, Korea.
authors.forename: Haeri
authors.initials: H
authors.lastname: Im
authors.affiliation: Department of Chemistry, Sookmyung Women's University, Hyochangwongil 52, Yongsanku, Seoul, 140-742, Korea.
authors.forename: Sunhee
authors.initials: S
authors.lastname: Cho
authors.affiliation: Department of Chemistry, Sookmyung Women's University, Hyochangwongil 52, Yongsanku, Seoul, 140-742, Korea.
authors.forename: Jong Young
authors.initials: JY
authors.lastname: Joung
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kodama
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kono
authors.affiliation: Department of Chemistry, Sookmyung Women's University, Hyochangwongil 52, Yongsanku, Seoul, 140-742, Korea. sihyun@sm.ac.kr.
authors.forename: Sihyun
authors.initials: S
authors.lastname: Ham
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1, Gakuen-cho, Naka-ku, Osaka, 599-8531, Japan. fujii@b.s.osakafu-u.ac.jp.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Fujii
mesh_terms: D000595:Amino Acid Sequence; D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D045744:Cell Line, Tumor; D015195:Drug Design; D006801:Humans; D062105:Molecular Docking Simulation; D010456:Peptides, Cyclic / Q000737:chemistry* / Q000494:pharmacology*; D000072756:Protein Conformation, alpha-Helical; D025941:Protein Interaction Mapping; D060066:Protein Interaction Maps / Q000187:drug effects*; D051736:Proto-Oncogene Proteins c-mdm2 / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism
chemical_list: D010456:Peptides, Cyclic; D016159:Tumor Suppressor Protein p53; D001120:Arginine; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2
keywords: cell-penetrating peptides; epitope grafting; helix-loop-helix peptides; inhibitors; protein-protein interactions