title: Development of helix-stabilized cell-penetrating peptides containing cationic α,α-disubstituted amino acids as helical promoters.
abstract: Cell-penetrating peptides (CPP) have attracted many scientists' attention as intracellular delivery tools due to their high cargo molecule transportation efficiency and low cytotoxicity. Therefore, in many research fields CPP, such as HIV-Tat and oligoarginine (Rn), are used to deliver hydrophilic drugs and biomolecules, including proteins, DNA, and RNA. We designed four types of CPP that contained cationic α,α-disubstituted amino acids (ApiC2Guand ApiC4Gu) as helical promoters; i.e., 1-4 [FAM-β-Ala-(l-Arg-l-Arg-Xaa)3-(Gly)3-NH2(1: Xaa=ApiC2Gu, 2: Xaa=ApiC4Gu), 3: FAM-β-Ala-(l-Arg)8-ApiC2Gu-(Gly)3-NH2, and 4: FAM-β-Ala-(l-Arg)5-ApiC2Gu-(l-Arg)2-ApiC2Gu-(Gly)3-NH2], and investigated their preferred secondary structures and cell membrane-penetrating ability. As a result, we found that the permeation efficiency of the CPP was affected by the number of helical promoters in their sequences. Specially, peptide 1, which contained three ApiC2Guresidues, formed a stable helical structure and passed through the cell membrane more efficiently than the other peptides. Moreover, it was demonstrated that the spatial arrangement of the peptides' side chains also influenced their permeability and the helical stabilization of their main chains.
authors.affiliation: National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya, Tokyo 158-8501, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Yamashita
authors.affiliation: National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya, Tokyo 158-8501, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Misawa
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Oba
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya, Tokyo 158-8501, Japan.
authors.forename: Mikihiko
authors.initials: M
authors.lastname: Naito
authors.affiliation: National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya, Tokyo 158-8501, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kurihara
authors.affiliation: National Institute of Health Sciences, 1-18-1, Kamiyoga, Setagaya, Tokyo 158-8501, Japan. Electronic address: demizu@nihs.go.jp.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Demizu
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D002460:Cell Line; D057846:Cell-Penetrating Peptides / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D006801:Humans; D013058:Mass Spectrometry; D018613:Microscopy, Confocal; D011487:Protein Conformation
chemical_list: D000596:Amino Acids; D057846:Cell-Penetrating Peptides
keywords: Cell penetrating peptide; Helical structure; pDNA delivery; α,α-disubstituted amino acid