title: In vitro creation of amyloid fibrils from native and Arg124Cys mutated betaIGH3((110-131)) peptides, and its relevance for lattice corneal amyloid dystrophy type I.
abstract: BetaIGH3 protein has been recently involved in the pathogenesis of blinding corneal diseases, some of which have characteristic amyloid corneal deposits. The 124 codon of the betaig-h3 gene seems to be crucial for the amyloidogenicity of the protein product. We presently report an in vitro system that reproducibly forms amyloid fibrils from betaIGH3((110-131)) derived peptides. We also assessed the differences in fibril formation of two 22-amino acid peptides centered on the 124 residue: the native form and the Arg124Cys peptide (mutation linked to lattice corneal amyloid dystrophy type 1). After dialysis of Arg124Cys peptide against PBS 1/15 M pH 7.4 for 72 hours, Congo red staining and electron microscopy demonstrated the presence of abundant material fulfilling the criteria of amyloid. Quantitative analysis with thioflavine T fluorescence studies confirmed the high capacity of Arg124Cys peptide to form amyloid fibrils when compared to the native form.
authors.affiliation: Institut de Génétique Humaine, CNRS UPR 1142, Montpellier, France.
authors.forename: C F
authors.initials: CF
authors.lastname: Schmitt-Bernard
authors.forename: A
authors.initials: A
authors.lastname: Chavanieu
authors.forename: J
authors.initials: J
authors.lastname: Derancourt
authors.forename: B
authors.initials: B
authors.lastname: Arnaud
authors.forename: J G
authors.initials: JG
authors.lastname: Demaille
authors.forename: B
authors.initials: B
authors.lastname: Calas
authors.forename: A
authors.initials: A
authors.lastname: Argiles
mesh_terms: D000595:Amino Acid Sequence; D000682:Amyloid / Q000096:biosynthesis*; D011232:Chemical Precipitation; D003317:Corneal Dystrophies, Hereditary / Q000209:etiology / Q000235:genetics* / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D006801:Humans; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009363:Neoplasm Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein
chemical_list: D000682:Amyloid; D016326:Extracellular Matrix Proteins; D009363:Neoplasm Proteins; D010446:Peptide Fragments; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein