title: Recombinant amyloidogenic domain of ApoA-I: analysis of its fibrillogenic potential.
abstract: A variety of amyloid diseases are associated with fibrillar aggregates from N-terminal fragments of ApoA-I generated through a largely unexplored multi-step process. The understanding of the molecular mechanism is impaired by the lack of suitable amounts of the fibrillogenic polypeptides that could not be produced by recombinant methods so far. We report the production and the conformational analysis of recombinant ApoA-I 1-93 fragment. Similarly to the polypeptide isolated ex vivo, a pH switch from 7 to 4 induces a fast and reversible conformational transition to a helical state and leads to the identification of a key intermediate in the fibrillogenesis process. Limited proteolysis experiments suggested that the C-terminal region is involved in helix formation. The recombinant polypeptide generates fibrils at pH 4 on a time scale comparable with that of the native fragment. These findings open the way to studies on structural, thermodynamic, and kinetic aspects of ApoA-I fibrillogenesis.
authors.affiliation: Istituto di Biostrutture e Bioimmagini, CNR, Napoli 80134, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Di Gaetano
authors.forename: Fulvio
authors.initials: F
authors.lastname: Guglielmi
authors.forename: Angela
authors.initials: A
authors.lastname: Arciello
authors.forename: Palma
authors.initials: P
authors.lastname: Mangione
authors.forename: Maria
authors.initials: M
authors.lastname: Monti
authors.forename: Daniela
authors.initials: D
authors.lastname: Pagnozzi
authors.forename: Sara
authors.initials: S
authors.lastname: Raimondi
authors.forename: Sofia
authors.initials: S
authors.lastname: Giorgetti
authors.forename: Stefania
authors.initials: S
authors.lastname: Orrù
authors.forename: Claudio
authors.initials: C
authors.lastname: Canale
authors.forename: Piero
authors.initials: P
authors.lastname: Pucci
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Dobson
authors.forename: Vittorio
authors.initials: V
authors.lastname: Bellotti
authors.forename: Renata
authors.initials: R
authors.lastname: Piccoli
mesh_terms: D000682:Amyloid / Q000737:chemistry* / Q000648:ultrastructure*; D016632:Apolipoprotein A-I / Q000737:chemistry* / Q000648:ultrastructure*; D001665:Binding Sites; D019281:Dimerization; D006863:Hydrogen-Ion Concentration; D046912:Multiprotein Complexes / Q000737:chemistry / Q000648:ultrastructure; D011485:Protein Binding
chemical_list: D000682:Amyloid; D016632:Apolipoprotein A-I; D046912:Multiprotein Complexes