title: Amyloid formation characteristics of GNNQQNY from yeast prion protein Sup35 and its seeding with heterogeneous polypeptides.
abstract: Sup35 is a prion-like protein from yeast and shares the ability to transmit its aberrant fold and to aggregate into amyloid fibrils.7GNNQQNY13from the prion-determining domain of Sup35 was reported to form an amyloid. We first investigated the self-aggregation transition behavior of GNNQQNY to the β-sheet amyloid state under various conditions. Mechanical stirring using a magnetic bar resulted in accelerated aggregation of the GNNQQNY. The aggregation rate of GNNQQNY was also dependent on its concentration; the higher the GNNQQNY concentration, the faster the aggregation. Circular dichroism and Fourier transform-infrared spectral data indicated the formation of the β-sheet structure in the GNNQQNY aggregates. The fluorescence experiments using an amyloid-specific thioflavin T also demonstrated that the GNNQQNY aggregates formed the amyloid structures. The amyloid structure of the GNNQQNY aggregates served as seeds for the elongation of the monomeric GNNQQNY in the solution state. We further studied the ability of the GNNQQNY amyloid fibrils to act as seeds for the elongation of the amyloid-forming monomeric proteins (albumin, lysozyme and insulin). The cross-seeding experiments suggested that the GNNQQNY aggregate could possibly promote the amyloid fibril formation of heterogeneous insulin. The inverse monomeric GNNQQNY would have a binding capacity for the heterogeneous already-formed amyloid-β fibrils on a mice brain section. These basic data could be informative for elucidating the pathogenic and/or propagation mechanisms of prion agents and developing effective therapeutics and/or diagnosis for prion diseases.
authors.affiliation: Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan. Electronic address: haratake@ph.sojo-u.ac.jp.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Haratake
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Takiguchi
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Naho
authors.initials: N
authors.lastname: Masuda
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Sakura
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fuchigami
authors.affiliation: Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan. Electronic address: morio@nagasaki-u.ac.jp.
authors.forename: Morio
authors.initials: M
authors.lastname: Nakayama
mesh_terms: D000595:Amino Acid Sequence; D016229:Amyloid beta-Peptides / Q000737:chemistry*; D000818:Animals; D052160:Benzothiazoles; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D007328:Insulin / Q000737:chemistry; D051379:Mice; D008822:Mice, Transgenic; D009113:Muramidase / Q000737:chemistry; D010454:Peptide Termination Factors / Q000008:administration & dosage / Q000737:chemistry*; D000072002:Prion Proteins / Q000737:chemistry*; D066329:Protein Aggregates; D066263:Protein Aggregation, Pathological / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D000072757:Protein Conformation, beta-Strand; D017510:Protein Folding; D012441:Saccharomyces cerevisiae / Q000737:chemistry; D029701:Saccharomyces cerevisiae Proteins / Q000008:administration & dosage / Q000737:chemistry*; D012709:Serum Albumin / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013844:Thiazoles
chemical_list: D016229:Amyloid beta-Peptides; D052160:Benzothiazoles; D007328:Insulin; D010454:Peptide Termination Factors; D000072002:Prion Proteins; D066329:Protein Aggregates; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012709:Serum Albumin; D013844:Thiazoles; C009462:thioflavin T; D009113:Muramidase
keywords: Aggregation; Amyloid; Prion; Seeding; Thioflavin T; Yeast; β-Sheet