Development of a Cell-penetrating Peptide that Exhibits Responsive Changes in its Secondary Structure in the Cellular Environment

July 28, 2017

Title

Development of a Cell-penetrating Peptide that Exhibits Responsive Changes in its Secondary Structure in the Cellular Environment

Author

Hiroko Yamashita, Takuma Kato, Makoto Oba, Takashi Misawa, Takayuki Hattori, Nobumichi Ohoka, Masakazu Tanaka, Mikihiko Naito, Masaaki Kurihara, Yosuke Demizu

Year

2016

Journal

Scientific Reports

Abstract

Cell-penetrating peptides (CPP) are received a lot of attention as an intracellular delivery tool for hydrophilic molecules such as drugs, proteins, and DNAs. We designed and synthesized nona-arginine analogues 1–5 [FAM-β-Ala-(L-Arg-L-Arg-L-Pro)3-(Gly)3-NH2 (1), FAM-β-Ala-(L-Arg-L-Arg-L-ProNH2)3-(Gly)3-NH2 (2), FAM-β-Ala-(L-Arg-L-Arg-L-ProGu)3-(Gly)3-NH2 (3), FAM-β-Ala-(L-Arg)2-(L-ProGu)2-(L-Arg)4-L-ProGu-(Gly)3-NH2 (4), and FAM-β-Ala-(L-Arg)6-(L-ProGu)3-(Gly)3-NH2 (5)] containing L-proline (L-Pro) or cationic proline derivatives (L-ProNH2and L-ProGu), and investigated their cell-penetrating abilities. Interestingly, only peptide 3 having the side-chain guanidinyl L-ProGuexhibited a secondary structural change in cellular environment. Specifically, peptide 3 formed a random structure in hydrophilic conditions, whereas it formed a helical structure under amphipathic conditions. Furthermore, during cellular permeability tests, peptide 3demonstrated greater cell-penetrating activity than other peptides and effectively transported plasmid DNA into HeLa cells. Thus, L-ProGu-containing peptide 3 may be a useful candidate as a gene delivery carrier.

Instrument

J-720

Keywords

Circular dichroism, Secondary structure, Vesicle interactions, Biochemistry