Endocytic vesicle rupture is a conserved mechanism of cellular invasion by amyloid proteins Journal Article


Authors: Flavin, W. P.; Bousset, L.; Green, Z. C.; Chu, Y.; Skarpathiotis, S.; Chaney, M. J.; Kordower, J. H.; Melki, R.; Campbell, E. M.
Article Title: Endocytic vesicle rupture is a conserved mechanism of cellular invasion by amyloid proteins
Abstract: Numerous pathological amyloid proteins spread from cell to cell during neurodegenerative disease, facilitating the propagation of cellular pathology and disease progression. Understanding the mechanism by which disease-associated amyloid protein assemblies enter target cells and induce cellular dysfunction is, therefore, key to understanding the progressive nature of such neurodegenerative diseases. In this study, we utilized an imaging-based assay to monitor the ability of disease-associated amyloid assemblies to rupture intracellular vesicles following endocytosis. We observe that the ability to induce vesicle rupture is a common feature of alpha-synuclein (alpha-syn) assemblies, as assemblies derived from WT or familial disease-associated mutant alpha-syn all exhibited the ability to induce vesicle rupture. Similarly, different conformational strains of WT alpha-syn assemblies, but not monomeric or oligomeric forms, efficiently induced vesicle rupture following endocytosis. The ability to induce vesicle rupture was not specific to alpha-syn, as amyloid assemblies of tau and huntingtin Exon1 with pathologic polyglutamine repeats also exhibited the ability to induce vesicle rupture. We also observe that vesicles ruptured by alpha-syn are positive for the autophagic marker LC3 and can accumulate and fuse into large, intracellular structures resembling Lewy bodies in vitro. Finally, we show that the same markers of vesicle rupture surround Lewy bodies in brain sections from PD patients. These data underscore the importance of this conserved endocytic vesicle rupture event as a damaging mechanism of cellular invasion by amyloid assemblies of multiple neurodegenerative disease-associated proteins, and suggest that proteinaceous inclusions such as Lewy bodies form as a consequence of continued fusion of autophagic vesicles in cells unable to degrade ruptured vesicles and their amyloid contents.
Journal Title: Acta Neuropathologica
ISSN: 1432-0533; 0001-6322
Publisher: Unknown  
Journal Place: Germany
Date Published: 2017
Language: eng
DOI/URL:
Notes: LR: 20170520; JID: 0412041; OTO: NOTNLM; 2016/12/12 [received]; 2017/05/08 [accepted]; 2017/04/14 [revised]; aheadofprint