Skip to main content

 9J4E | pdb_00009j4e

Cryo-EM structure of P25alpha full-length fibril


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.32 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: HELICAL 

wwPDB Validation 3D Report Full Report

Validation slider image for 9J4E

This is version 1.2 of the entry. See complete history. 

Literature

TPPP/p25 amyloid seeding activity as a specific biomarker for multiple system atrophy.

Zeng, S., Zhang, S., Zhang, S., Fan, Y., Xia, W., Chen, F., Huang, C., Lv, S., Lu, J., Sun, Y., Liu, K., Li, Y., Zhang, Y., Wang, J., Liu, C., Li, D.

(2026) Cell 189: 4724

  • DOI: https://doi.org/10.1016/j.cell.2026.04.050
  • Primary Citation Related Structures: 
    9J4D, 9J4E, 9J4F

  • PubMed Abstract: 

    Detection of α-synuclein (α-syn) amyloid seeds in human biofluids has attracted great interest for clinical diagnosis of synucleinopathies. However, as a common biomarker, α-syn lacks specificity in reliably differentiating distinct disorders. Here, we report tubulin polymerization promoting protein (TPPP/p25) as a cerebrospinal fluid (CSF) biomarker for the specific diagnosis of multiple system atrophy (MSA). We demonstrate that native TPPP/p25 is self-protected against amyloid aggregation, while disease-related mutation disrupts this protection, triggering TPPP/p25 aggregation. Cryo-electron microscopy (cryo-EM) analysis reveals that the well-folded core domain (CORE) undergoes large conformational changes to mediate amyloid formation. Based on this insight, we developed a seed amplification assay using a minimized CORE (miniCORE) monomer, which detects TPPP/p25 amyloid seeds in CSF and robustly differentiates MSA from Parkinson's disease (PD) and other neurodegenerative diseases. Our findings establish misfolded TPPP/p25 as a promising, specific biomarker in biofluids for MSA diagnosis.


  • Organizational Affiliation: 
    • Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200030, China; Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai 200240, China.

Macromolecule Content 

  • Total Structure Weight: 142.44 kDa 
  • Atom Count: 1,758 
  • Modeled Residue Count: 222 
  • Deposited Residue Count: 1,314 
  • Unique protein chains: 1

Macromolecules

Find similar proteins by:|  3D Structure
Entity ID: 1
MoleculeChains  Sequence LengthOrganismDetailsImage
Tubulin polymerization-promoting protein219Homo sapiensMutation(s): 0 
Gene Names: TPPP, TPPP1
EC: 3.6.5
UniProt & NIH Common Fund Data Resources
Find proteins for O94811 (Homo sapiens)
Explore O94811 
Go to UniProtKB:  O94811
PHAROS:  O94811
GTEx:  ENSG00000171368 
Entity Groups
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO94811
Sequence Annotations
Expand
Reference Sequence

Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.32 Å
  • Aggregation State: FILAMENT 
  • Reconstruction Method: HELICAL 

Structure Validation

View Full Validation Report



Entry History 

& Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Not funded--

Revision History  (Full details and data files)

  • Version 1.0: 2025-08-13
    Type: Initial release
  • Version 1.1: 2026-06-03
    Changes: Data collection, Database references
  • Version 1.2: 2026-08-05
    Changes: Data collection, Database references