Stochastic misfolding drives the emergence of distinct alpha-synuclein strains.
So, R.W.L., Frieg, B., Camino, J.D., Situ, C., Metri, M.N., Silver, N.R.G., Li, L.Y., Mao, A., Stuart, E., Schroder, G.F., Watts, J.C.(2026) Neuron 
- PubMed: 41763203 
- DOI: https://doi.org/10.1016/j.neuron.2026.01.014
- Primary Citation of Related Structures:  
9RB3, 9RB6, 9RB7, 9RB8, 9RB9, 9RBA, 9RBB - PubMed Abstract: 
α-Synuclein conformational strains provide a potential explanation for the clinical and pathological differences among synucleinopathies such as Parkinson's disease and multiple system atrophy. However, how distinct α-synuclein strains arise remains unknown. Here, we observed conformational heterogeneity between individual preparations of α-synuclein pre-formed fibrils (PFFs) generated by polymerizing wild-type or A53T-mutant human α-synuclein under identical conditions. Moreover, we found that α-synuclein aggregates formed spontaneously in the brains of a transgenic synucleinopathy mouse model are conformationally diverse. Propagation of stochastically formed PFF- and brain-derived α-synuclein strains in mice initiated several distinct synucleinopathies. The conformational diversity of α-synuclein aggregates across PFF preparations and between individual mice demonstrates that α-synuclein can spontaneously form multiple self-propagating strains within an identical environment. This suggests that stochastic misfolding into distinct aggregate structures drives the emergence of α-synuclein strains and reveals that the intrinsic variability of common synucleinopathy research tools must be considered when designing and interpreting experiments.
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON M5T 0S8, Canada; Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada.
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