title: Membrane effects of N-terminal fragment of apolipoprotein A-I: a fluorescent probe study.
abstract: The binding of monomeric and aggregated variants of 1-83 N-terminal fragment of apolipoprotein A-I with substitution mutations G26R, G26R/W@8, G26R/W@50 and G26R/W@72 to the model lipid membranes composed of phosphatidylcholine and its mixture with cholesterol has been investigated using fluorescent probes pyrene and Laurdan. Examination of pyrene spectral behavior did not reveal any marked influence of apoA-I mutants on the hydrocarbon region of lipid bilayer. In contrast, probing the membrane effects by Laurdan revealed decrease in the probe generalized polarization in the presence of aggregated proteins. suggesting that oligomeric and fibrillar apoA-I species induce increase in hydration degree and reduction of lipid packing density in the membrane interfacial region. These findings may shed light on molecular details of amyloid cytotoxicity.
authors.affiliation: Department of Nuclear and Medical Physics, V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkov, 61077, Ukraine, valtrusova@yahoo.com.
authors.forename: Valeriya
authors.initials: V
authors.lastname: Trusova
authors.forename: Galyna
authors.initials: G
authors.lastname: Gorbenko
authors.forename: Mykhailo
authors.initials: M
authors.lastname: Girych
authors.forename: Emi
authors.initials: E
authors.lastname: Adachi
authors.forename: Chiharu
authors.initials: C
authors.lastname: Mizuguchi
authors.forename: Rohit
authors.initials: R
authors.lastname: Sood
authors.forename: Paavo
authors.initials: P
authors.lastname: Kinnunen
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Saito
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000737:chemistry; D000595:Amino Acid Sequence; D000682:Amyloid / Q000737:chemistry; D016632:Apolipoprotein A-I / Q000737:chemistry*; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism*; D002784:Cholesterol / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D007848:Laurates / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000737:chemistry; D055503:Protein Multimerization; D011721:Pyrenes / Q000737:chemistry
chemical_list: D000682:Amyloid; D016632:Apolipoprotein A-I; D005456:Fluorescent Dyes; D007848:Laurates; D008051:Lipid Bilayers; D010446:Peptide Fragments; D010713:Phosphatidylcholines; D011721:Pyrenes; D002784:Cholesterol; C030984:pyrene; D015081:2-Naphthylamine; C065580:laurdan