title: Liposomal leakage induced by virus-derived peptides, viral proteins, and entire virions: rapid analysis by chip electrophoresis.
abstract: Permeabilization of model lipid membranes by virus-derived peptides, viral proteins, and entire virions of human rhinovirus was assessed by quantifying the release of a fluorescent dye from liposomes via a novel chip electrophoretic assay. Liposomal leakage readily occurred upon incubation with the pH-sensitive synthetic fusogenic peptide GALA and, less efficiently, with a 24mer peptide (P1-N) derived from the N-terminus of the capsid protein VP1 of human rhinovirus 2 (HRV2) at acidic pH. Negative stain transmission electron microscopy showed that liposomes incubated with the rhinovirus-derived peptide remained largely intact. At similar concentrations, the GALA peptide caused gross morphological changes of the liposomes. On a molar basis, the leakage-inducing efficiency of the P1 peptide was by about 2 orders of magnitude inferior to that of recombinant VP1 (from HRV89) and entire HRV2. This underscores the role in membrane destabilization of VP1 domains remote from the N-terminus and the arrangement of the peptide in the context of the icosahedral virion. Our method is rapid, requires tiny amounts of sample, and allows for the parallel determination of released and retained liposomal cargo.
authors.affiliation: Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna Biocenter (VBC), Vienna, Austria.
authors.forename: Victor U
authors.initials: VU
authors.lastname: Weiss
authors.forename: Gerhard
authors.initials: G
authors.lastname: Bilek
authors.forename: Angela
authors.initials: A
authors.lastname: Pickl-Herk
authors.forename: Xavier
authors.initials: X
authors.lastname: Subirats
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Niespodziana
authors.forename: Rudolf
authors.initials: R
authors.lastname: Valenta
authors.forename: Dieter
authors.initials: D
authors.lastname: Blaas
authors.forename: Ernst
authors.initials: E
authors.lastname: Kenndler
mesh_terms: D000595:Amino Acid Sequence; D004586:Electrophoresis / Q000379:methods*; D005456:Fluorescent Dyes; D006801:Humans; D008081:Liposomes / Q000378:metabolism*; D046529:Microscopy, Electron, Transmission; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D010455:Peptides / Q000378:metabolism*; D012229:Rhinovirus / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism*; D014771:Virion / Q000378:metabolism*
chemical_list: D005456:Fluorescent Dyes; D008081:Liposomes; D010455:Peptides; D014764:Viral Proteins