Correlation Engine 2.0
Clear Search sequence regions


Sizes of these terms reflect their relevance to your search.

Aggregation of proteins containing expanded polyglutamine (polyQ) repeats is the cytopathologic hallmark of a group of dominantly inherited neurodegenerative diseases, including Huntington's disease (HD). Huntingtin (Htt), the disease protein of HD, forms amyloid-like fibrils by liquid-to-solid phase transition. Macroautophagy has been proposed to clear polyQ aggregates, but the efficiency of aggrephagy is limited. Here, we used cryo-electron tomography to visualize the interactions of autophagosomes with polyQ aggregates in cultured cells in situ. We found that an amorphous aggregate phase exists next to the radially organized polyQ fibrils. Autophagosomes preferentially engulfed this amorphous material, mediated by interactions between the autophagy receptor p62/SQSTM1 and the non-fibrillar aggregate surface. In contrast, amyloid fibrils excluded p62 and evaded clearance, resulting in trapping of autophagic structures. These results suggest that the limited efficiency of autophagy in clearing polyQ aggregates is due to the inability of autophagosomes to interact productively with the non-deformable, fibrillar disease aggregates. Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

Citation

Dorothy Y Zhao, Felix J B Bäuerlein, Itika Saha, F Ulrich Hartl, Wolfgang Baumeister, Florian Wilfling. Autophagy preferentially degrades non-fibrillar polyQ aggregates. Molecular cell. 2024 May 16;84(10):1980-1994.e8

Expand section icon Mesh Tags

Expand section icon Substances


PMID: 38759629

View Full Text