Dynamic Properties of Human α-Synuclein Related to Propensity to Amyloid Fibril Formation.
J Mol Biol
; 431(17): 3229-3245, 2019 08 09.
Article
em En
| MEDLINE
| ID: mdl-31181290
ABSTRACT
α-Synuclein (αSyn) is an intrinsically disordered protein that can form amyloid fibrils. Fibrils of αSyn are implicated with the pathogenesis of Parkinson's disease and other synucleinopathies. Elucidating the mechanism of fibril formation of αSyn is therefore important for understanding the mechanism of the pathogenesis of these diseases. Fibril formation of αSyn is sensitive to solution conditions, suggesting that fibril formation of αSyn arises from the changes in its inherent physico-chemical properties, particularly its dynamic properties because intrinsically disordered proteins such as αSyn utilize their inherent flexibility to function. Characterizing these properties under various conditions should provide insights into the mechanism of fibril formation. Here, using the quasielastic neutron scattering and small-angle x-ray scattering techniques, we investigated the dynamic and structural properties of αSyn under the conditions, where mature fibrils are formed (pHâ¯7.4 with a high salt concentration), where clumping of short fibrils occurs (pHâ¯4.0), and where fibril formation is not completed (pHâ¯7.4). The small-angle x-ray scattering measurements showed that the extended structures at pHâ¯7.4 with a high salt concentration become compact at pHâ¯4.0 and 7.4. The quasielastic neutron scattering measurements showed that both intra-molecular segmental motions and local motions such as side-chain motions are enhanced at pHâ¯7.4 with a high salt concentration, compared to those at pHâ¯7.4 without salt, whereas only the local motions are enhanced at pHâ¯4.0. These results imply that fibril formation of αSyn requires not only the enhanced local motions but also the segmental motions such that proper inter-molecular interactions are possible.
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Base de dados:
MEDLINE
Assunto principal:
Alfa-Sinucleína
/
Amiloide
Limite:
Humans
Idioma:
En
Revista:
J Mol Biol
Ano de publicação:
2019
Tipo de documento:
Article