9CD9

Structure of type II-2 alpha-synuclein filament from multiple system atrophy

• PDB DOI: https://doi.org/10.2210/pdb9CD9/pdb
• EM Map EMD-45464: EMDB EMDataResource

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


• Deposited: 2024-06-24 Released: 2024-11-27 
• Deposition Author(s): Yan, N.L., Candido, F., Tse, E., Melo, A.A., Southworth, D.R., Merz, G.E.
• Funding Organization(s): Other private

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.20 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

Literature

Cryo-EM structure of a novel alpha-synuclein filament subtype from multiple system atrophy.

Yan, N.L., Candido, F., Tse, E., Melo, A.A., Prusiner, S.B., Mordes, D.A., Southworth, D.R., Paras, N.A., Merz, G.E.

(2024) FEBS Lett 

• PubMed: 39511911 
• DOI: https://doi.org/10.1002/1873-3468.15048
• Primary Citation of Related Structures:  
  9CD9, 9CDA


• PubMed Abstract: 
  

  Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by accumulation of α-synuclein cross-β amyloid filaments in the brain. Previous structural studies of these filaments by cryo-electron microscopy (cryo-EM) revealed three discrete folds distinct from α-synuclein filaments associated with other neurodegenerative diseases. Here, we use cryo-EM to identify a novel, low-populated MSA filament subtype (designated Type I ₂ ) in addition to a predominant class comprising MSA Type II ₂ filaments. The 3.3-Å resolution structure of the Type I ₂ filament reveals a fold consisting of two asymmetric protofilaments, one of which adopts a novel structure that is chimeric between two previously reported protofilaments. These results further define MSA-specific folds of α-synuclein filaments and have implications for designing MSA diagnostics and therapeutics.

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Organizational Affiliation: 

Institute for Neurodegenerative Diseases, Weill Institute for Neurosciences, University of California San Francisco, CA, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 22-mer - A11B11 

Biological assembly 1 assigned by authors and generated by (software)

Biological Assembly Evidence: electron microscopy

Macromolecule Content

• Total Structure Weight: 318.47 kDa 
• Atom Count: 10,989 
• Modelled Residue Count: 1,606 
• Deposited Residue Count: 3,080 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alpha-synuclein	A [auth E], B [auth F], C [auth G], D [auth H], E [auth I], F [auth J], G [auth U], H [auth V], I [auth W], J [auth X], K [auth Y], L [auth Z], M [auth K], N [auth L], O [auth M], P [auth N], Q [auth O], R [auth P], S [auth Q], T [auth R], U [auth S], V [auth T]	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

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.20 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: HELICAL 

EM Software:

Task	Software Package	Version
MODEL REFINEMENT	PHENIX
RECONSTRUCTION	RELION

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2024-11-27 
Deposition Author(s): Yan, N.L., Candido, F., Tse, E., Melo, A.A., Southworth, D.R., Merz, G.E.

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Funding Organization	Location	Grant Number
Other private	United States	HU0001-21-2-065, subaward 5802
Other private	United States	--
Other private	United States	--

Revision History  

• Version 1.0: 2024-11-27
  Type: Initial release