title: Phospholipid membrane permeability of peptide nucleic acid.
abstract: Phospholipid vesicles (liposomes) as membrane models have been used to study the penetration properties of peptide nucleic acid (PNA), a new DNA analog in which the nucleobases are attached to a pseudo-peptide backbone. The liposomes were characterised by carboxyfluorescein efflux, light-scattering and cryogenic transmission electron microscopy. The liposome structure was found not to be affected by the incorporation of PNA or an oligonucleotide. Two 10-mer fluorescein-labelled PNAs were found to have low efflux rates (half-times of 5.5 and 11 days), comparable to that of a 10-mer oligonucleotide (half-time of 7 days). We conclude that passive diffusion of unmodified PNA over the lipid membrane is not likely to be an effective way of transport into biological cells.
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000737:chemistry*; D005452:Fluoresceins; D005456:Fluorescent Dyes; D005615:Freezing; D007700:Kinetics; D008081:Liposomes; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*; D016376:Oligonucleotides, Antisense / Q000737:chemistry*; D010539:Permeability; D010743:Phospholipids; D013329:Structure-Activity Relationship
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; D008081:Liposomes; D009838:Oligodeoxyribonucleotides; D016376:Oligonucleotides, Antisense; D010743:Phospholipids; C024098:6-carboxyfluorescein; D004247:DNA