title: Switch-peptides: design and characterization of controllable super-amyloid-forming host-guest peptides as tools for identifying anti-amyloid agents.
abstract: Several amyloid-forming proteins are characterized by the presence of hydrophobic and highly amyloidogenic core sequences that play critical roles in the initiation and progression of amyloid fibril formation. Therefore targeting these sequences represents a viable strategy for identifying candidate molecules that could interfere with amyloid formation and toxicity of the parent proteins. However, the highly amyloidogenic and insoluble nature of these sequences has hampered efforts to develop high-throughput fibrillization assays. Here we describe the design and characterization of host-guest switch peptides that can be used for in vitro mechanistic and screening studies that are aimed at discovering aggregation inhibitors that target highly amyloidogenic sequences. These model systems are based on a host-guest system where the amyloidogenic sequence (guest peptide) is flanked by two beta-sheet-promoting (Leu-Ser)(n) oligomers as host sequences. Two host-guest peptides were prepared by using the hydrophobic core of Abeta comprising residues 14-24 (HQKLVFFAEDV) as the guest peptide with switch elements inserted within (peptide 1) or at the N and C termini of the guest peptide (peptide 2). Both model peptides can be triggered to undergo rapid self-assembly and amyloid formation in a highly controllable manner and their fibrillization kinetics is tuneable by manipulating solution conditions (for example, peptide concentration and pH). The fibrillization of both peptides reproduces many features of the full-length Abeta peptides and can be inhibited by known inhibitors of Abeta fibril formation. Our results suggest that this approach can be extended to other amyloid proteins and should facilitate the discovery of small-molecule aggregation inhibitors and the development of more efficacious anti-amyloid agents to treat and/or reverse the pathogenesis of neurodegenerative and systemic amyloid diseases.
authors.affiliation: Institute of Chemical Sciences and Engineering (ISIC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Marie-Stéphanie
authors.initials: MS
authors.lastname: Camus
authors.forename: Sonia
authors.initials: S
authors.lastname: Dos Santos
authors.forename: Arunan
authors.initials: A
authors.lastname: Chandravarkar
authors.forename: Bhubaneswar
authors.initials: B
authors.lastname: Mandal
authors.forename: Adrian W
authors.initials: AW
authors.lastname: Schmid
authors.forename: Gabriele
authors.initials: G
authors.lastname: Tuchscherer
authors.forename: Manfred
authors.initials: M
authors.lastname: Mutter
authors.forename: Hilal A
authors.initials: HA
authors.lastname: Lashuel
mesh_terms: D000595:Amino Acid Sequence; D000682:Amyloid / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D015195:Drug Design; D004353:Drug Evaluation, Preclinical; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D017433:Protein Structure, Secondary; D054852:Small Molecule Libraries / Q000494:pharmacology
chemical_list: D000682:Amyloid; D010455:Peptides; D054852:Small Molecule Libraries