title: Ultrasonication-dependent acceleration of amyloid fibril formation.
abstract: Amyloid fibrils, similar to crystals, form through nucleation and growth. Because of the high free-energy barrier of nucleation, the spontaneous formation of amyloid fibrils occurs only after a long lag phase. Ultrasonication is useful for inducing amyloid nucleation and thus for forming fibrils, while the use of a microplate reader with thioflavin T fluorescence is suitable for detecting fibrils in many samples simultaneously. Combining the use of ultrasonication and microplate reader, we propose an efficient approach to studying the potential of proteins to form amyloid fibrils. With β(2)-microglobulin, an amyloidogenic protein responsible for dialysis-related amyloidosis, fibrils formed within a few minutes at pH 2.5. Even under neutral pH conditions, fibrils formed after a lag time of 1.5 h. The results propose that fibril formation is a physical reaction that is largely limited by the high free-energy barrier, which can be effectively reduced by ultrasonication. This approach will be useful for developing a high-throughput assay of the amyloidogenicity of proteins.
authors.affiliation: Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
authors.forename: Masatomo
authors.initials: M
authors.lastname: So
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yagi
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Sakurai
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ogi
authors.forename: Hironobu
authors.initials: H
authors.lastname: Naiki
authors.forename: Yuji
authors.initials: Y
authors.lastname: Goto
mesh_terms: D000054:Acceleration; D000682:Amyloid / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D004305:Dose-Response Relationship, Drug; D019220:High-Energy Shock Waves; D057166:High-Throughput Screening Assays / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008954:Models, Biological; D009994:Osmolar Concentration; D055503:Protein Multimerization / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects*; D012965:Sodium Chloride / Q000494:pharmacology; D013010:Sonication / Q000379:methods*
chemical_list: D000682:Amyloid; D012965:Sodium Chloride