title: Quantized folding of plasmid DNA condensed with block catiomer into characteristic rod structures promoting transgene efficacy.
abstract: Highly regulated folding of plasmid DNA (pDNA) through polyion complexation with the synthetic block catiomer, poly(ethylene glycol)-block-poly(L-lysine) (PEG-PLys), was found to occur in such a way that rod structures are formed with a quantized length of 1/2(n + 1) of the original pDNA length folding by n times. The folding process of pDNA was elucidated with regard to rigidity of the double-stranded DNA structure and topological restriction of the supercoiled closed-circular form, and a mechanism based on Euler's buckling theory was proposed. Folded pDNA exhibited higher gene expression efficiency compared to naked pDNA in a cell-free transcription/translation assay system, indicating that the packaging of pDNA into a polyion complex core surrounded by a PEG palisade is a promising strategy for constructing nonviral gene carrier systems. Extension of this finding may provide a reasonable model to further understand the packaging mechanism of supercoiled DNA structures in nature.
authors: Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors: Kensuke
authors: K
authors: Osada
authors: Hiroki
authors: H
authors: Oshima
authors: Daigo
authors: D
authors: Kobayashi
authors: Motoyoshi
authors: M
authors: Doi
authors: Manabu
authors: M
authors: Enoki
authors: Yuichi
authors: Y
authors: Yamasaki
authors: Kazunori
authors: K
authors: Kataoka
mesh_terms: D004247:DNA / Q000737:chemistry*; D008239:Lysine / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: C092361:poly(ethylene glycol) lysine copolymer; D011092:Polyethylene Glycols; D004247:DNA; D008239:Lysine