9OBP | pdb_00009obp

Cryo-EM structure of alpha-synuclein filaments derived from the frontal cortex of the case of atypical multiple system atrophy

• PDB DOI: https://doi.org/10.2210/pdb9OBP/pdb
• EM Map EMD-70295: EMDB EMDataResource

• Classification: PROTEIN FIBRIL
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 2025-04-23 Released: 2025-06-25 
• Deposition Author(s): Enomoto, M., Martinez-Valbuena, I., Forrest, S.L., Xu, X., Munhoz, R., Li, J., Rogaeva, E., Lang, A.E., Kovacs, G.G.
• Funding Organization(s): National Institutes of Health/National Institute on Aging (NIH/NIA)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.50 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

Lewy-MSA hybrid fold drives distinct neuronal alpha-synuclein pathology.

Enomoto, M., Martinez-Valbuena, I., Forrest, S.L., Xu, X., Munhoz, R.P., Li, J., Rogaeva, E., Lang, A.E., Kovacs, G.G.

(2025) Commun Biol 8: 929-929

• PubMed: 40523906 
• DOI: https://doi.org/10.1038/s42003-025-08355-7
• Primary Citation of Related Structures:  
  9E9X, 9OBP


• PubMed Abstract: 
  

  The ordered assembly of α-synuclein protein encoded by SNCA into filaments characterizes neurodegenerative synucleinopathies. Lewy body disease (LBD) shows predominantly neuronal and multiple system atrophy (MSA), predominantly oligodendrocytic α-synuclein pathology affecting subcortical brain structures. Based on cryo-electron microscopy, it was reported that the structures of α-synuclein filaments from LBD differ from MSA and juvenile-onset synucleinopathy (JOS). The rare atypical MSA subtype shows abundant neuronal argyrophilic α-synuclein inclusions in the limbic system. Current concepts indicate that disease entities are characterized by unique protofilament folds. Here we demonstrate that α-synuclein can form a Lewy-MSA hybrid fold, leading to the atypical histopathological form of MSA. Distinct biochemical characteristics of α-synuclein, as demonstrated by protease-sensitivity digestion assay, seed amplification assays (SAAs), and conformational stability assays (CSA), are also linked to cytopathological differences. We expand the current structure-based classification of α-synucleinopathies and propose that cell-specific protein pathologies can be associated with distinct filament folds.

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Organizational Affiliation: 
• Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada. [e-mail].
Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada.
Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.
Edmond J. Safra Program in Parkinson's Disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada.
Krembil Brain Institute, University Health Network, Toronto, ON, Canada.
Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON, Canada. [e-mail].
Edmond J. Safra Program in Parkinson's Disease and the Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada. [e-mail].
Krembil Brain Institute, University Health Network, Toronto, ON, Canada. [e-mail].
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada. [e-mail].
Laboratory Medicine Program, University Health Network, Toronto, ON, Canada. [e-mail].

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 15-mer - A5B5C5 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 15-mer - A5B5C1D1E1F1G1 

Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - C2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - C2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - C2 Local Symmetry: Cyclic - C2  (Explore in 3D)
Local Stoichiometry: Homo 2-mer - C2 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: electron microscopy

Macromolecule Content 

• Total Structure Weight: 146.98 kDa 
• Atom Count: 5,310 
• Modeled Residue Count: 775 
• Deposited Residue Count: 1,425 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-synuclein	A, B, C, D, E, F, G, H, I, J	140	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P37840 (Homo sapiens) Explore P37840  Go to UniProtKB:  P37840
PHAROS:  P37840 GTEx:  ENSG00000145335

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Unidentified protein	K, L, M, N, O	5	Homo sapiens	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.50 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX	1.21.2_5419

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2025-06-25 
Deposition Author(s): Enomoto, M., Martinez-Valbuena, I., Forrest, S.L., Xu, X., Munhoz, R., Li, J., Rogaeva, E., Lang, A.E., Kovacs, G.G.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute on Aging (NIH/NIA)	United States	--

Revision History  

• Version 1.0: 2025-06-25
  Type: Initial release
  
• Version 1.1: 2025-07-02
  Changes: Data collection, Database references