| Autor: |
Maho Yagi-Utsumi, Koichi Matsuo, Katsuhiko Yanagisawa, Kunihiko Gekko, Koichi Kato |
| Jazyk: |
angličtina |
| Rok vydání: |
2011 |
| Předmět: |
|
| Zdroj: |
International Journal of Alzheimer's Disease, Vol 2011 (2011) |
| Druh dokumentu: |
article |
| ISSN: |
2090-0252 |
| DOI: |
10.4061/2011/925073 |
| Popis: |
Clusters of GM1 gangliosides act as platforms for conformational transition of monomeric, unstructured amyloid β (Aβ) to its toxic β-structured aggregates. We have previously shown that Aβ(1–40) accommodated on the hydrophobic/hydrophilic interface of lyso-GM1 or GM1 micelles assumes α-helical structures under ganglioside-excess conditions. For better understanding of the mechanisms underlying the α-to-β conformational transition of Aβ on GM1 clusters, we performed spectroscopic characterization of Aβ(1–40) titrated with GM1. It was revealed that the thioflavin T- (ThT-) reactive β-structure is more populated in Aβ(1–40) under conditions where the Aβ(1–40) density on GM1 micelles is high. Under this circumstance, the C-terminal hydrophobic anchor Val39-Val40 shows two distinct conformational states that are reactive with ThT, while such Aβ species were not generated by smaller lyso-GM1 micelles. These findings suggest that GM1 clusters promote specific Aβ-Aβ interactions through their C-termini coupled with formation of the ThT-reactive β-structure depending on sizes and curvatures of the clusters. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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