Dynamic Properties of Human α-Synuclein Related to Propensity to Amyloid Fibril Formation

Publication date: Available online 8 June 2019Source: Journal of Molecular BiologyAuthor(s): Satoru Fujiwara, Fumiaki Kono, Tatsuhito Matsuo, Yasunobu Sugimoto, Tomoharu Matsumoto, Akihiro Narita, Kaoru ShibataAbstractα-synuclein (αSyn) is an intrinsically disordered protein (IDP) 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 IDPs 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 (QENS) and small-angle X-ray scattering (SAXS) techniques, we investigated the dynamic and structural properties of αSyn under the conditions, where mature fibrils are formed (pH 7.4 with a high salt concentration), where clumping of short fibrils occurs (pH 4.0), and where fibril formation is not completed (pH 7.4). The SAXS measurements showed that the extended structures at pH 7.4 with a high salt concentration become compact at pH 4.0 and 7.4. The QENS meas...
Source: Journal of Molecular Biology - Category: Molecular Biology Source Type: research