title: A C-terminal membrane anchor affects the interactions of prion proteins with lipid membranes.
abstract: Membrane attachment via a C-terminal glycosylphosphatidylinositol anchor is critical for conversion of PrP(C) into pathogenic PrP(Sc). Therefore the effects of the anchor on PrP structure and function need to be deciphered. Three PrP variants, including full-length PrP (residues 23-231, FL_PrP), N-terminally truncated PrP (residues 90-231, T_PrP), and PrP missing its central hydrophobic region (Δ105-125, ΔCR_PrP), were equipped with a C-terminal membrane anchor via a semisynthesis strategy. Analyses of the interactions of lipidated PrPs with phospholipid membranes demonstrated that C-terminal membrane attachment induces a different binding mode of PrP to membranes, distinct from that of non-lipidated PrPs, and influences the biochemical and conformational properties of PrPs. Additionally, fluorescence-based assays indicated pore formation by lipidated ΔCR_PrP, a variant that is known to be highly neurotoxic in transgenic mice. This finding was supported by using patch clamp electrophysiological measurements of cultured cells. These results provide new evidence for the role of the membrane anchor in PrP-lipid interactions, highlighting the importance of the N-terminal and the central hydrophobic domain in these interactions.
authors.affiliation: From the Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria.
authors.forename: Nam K
authors.initials: NK
authors.lastname: Chu
authors.affiliation: the Department of Pharmacology and Toxicology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, and.
authors.forename: Waheed
authors.initials: W
authors.lastname: Shabbir
authors.affiliation: the Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: Erin
authors.initials: E
authors.lastname: Bove-Fenderson
authors.affiliation: From the Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria.
authors.forename: Can
authors.initials: C
authors.lastname: Araman
authors.affiliation: the Department of Pharmacology and Toxicology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria, and.
authors.forename: Rosa
authors.initials: R
authors.lastname: Lemmens-Gruber
authors.affiliation: the Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118.
authors.forename: David A
authors.initials: DA
authors.lastname: Harris
authors.affiliation: From the Institute of Biological Chemistry, Faculty of Chemistry, University of Vienna, Währinger Strasse 38, 1090 Vienna, Austria, christian.becker@univie.ac.at.
authors.forename: Christian F W
authors.initials: CF
authors.lastname: Becker
mesh_terms: D009327:4-Chloro-7-nitrobenzofurazan / Q000378:metabolism; D000818:Animals; D055724:Electrophysiological Phenomena; D019286:Endopeptidase K / Q000378:metabolism; D005452:Fluoresceins / Q000378:metabolism; D005453:Fluorescence; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D007700:Kinetics; D008081:Liposomes / Q000378:metabolism / Q000648:ultrastructure; D008563:Membrane Lipids / Q000378:metabolism*; D051379:Mice; D050505:Mutant Proteins / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D011328:Prions / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D014364:Tryptophan / Q000378:metabolism
chemical_list: D005452:Fluoresceins; D017261:Glycosylphosphatidylinositols; D008081:Liposomes; D008563:Membrane Lipids; D050505:Mutant Proteins; D010455:Peptides; D010743:Phospholipids; D011328:Prions; D014364:Tryptophan; D019286:Endopeptidase K; D009327:4-Chloro-7-nitrobenzofurazan; C007740:fluorexon
keywords: Liposome; Membrane Anchor; Pore Formation; Prion; Protein Aggregation; Protein Chemistry; Protein Conformation; Protein Semisynthesis; lipid-Protein Interactions