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Study of Molecular Mechanisms of α-Synuclein Assembly: Insight into a Cross-β Structure in the N-Termini of New α-Synuclein Fibrils.

ABSTRACT: Parkinson's disease is characterized by the self-assembly of α-synuclein (AS), in which its aggregates accumulate in the substantia nigra. The molecular mechanisms of the self-assembly of AS are challenging because AS is a relatively large intrinsically disordered protein, consisting of 140 residues. It is known that the N-termini of AS contribute to the toxicity of the proteins; therefore, it is important to investigate the self-assembly structure of the N-termini on AS as well. There have been extensive efforts to investigate the structural fibrils of AS(1-140), which have shown that the N-termini are disordered and do not participate in the fibrillary structure. This study illustrates for the first time that the N-termini of AS play a crucial role in the self-assembly of AS. This study reveals a new structure of AS(1-140) fibrils, in which the N-termini are essential parts of the cross-β structure of the fibrillary structure. This study suggests that there are polymorphic states of the self-assembled AS(1-140). While the polymorphic states of the N-termini do not participate in the fibrillary structure and fluctuate, our predicted new fibrillary structure of the N-termini not only participates in the fibrillary structure but also stabilizes the fibrillary structure.

SUBMITTER: Bloch DN

PROVIDER: S-EPMC6044890 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Increased Dynamics of α-Synuclein Fibrils by β-Synuclein Leads to Reduced Seeding and Cytotoxicity.

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