Dynamics of oligomer and amyloid fibril formation by yeast prion Sup35 observed by high-speed atomic force microscopy.

ABSTRACT: The yeast prion protein Sup35, which contains intrinsically disordered regions, forms amyloid fibrils responsible for a prion phenotype [PSI ⁺]. Using high-speed atomic force microscopy (HS-AFM), we directly visualized the prion determinant domain (Sup35NM) and the formation of its oligomers and fibrils at subsecond and submolecular resolutions. Monomers with freely moving tail-like regions initially appeared in the images, and subsequently oligomers with distinct sizes of ∼1.7 and 3 to 4 nm progressively accumulated. Nevertheless, these oligomers did not form fibrils, even after an incubation for 2 h in the presence of monomers. Fibrils appeared after much longer monomer incubation. The fibril elongation occurred smoothly without discrete steps, suggesting gradual conver

SUBMITTER: Konno H 

PROVIDER: S-EPMC7149427 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature