Differential role of C-terminal truncations on alpha-synuclein pathology and Lewy body formation
Alpha-synuclein (aSyn) post-translational modifications (PTM), especially phosphorylation at serine 129 and C-terminal truncations, are highly enriched in Lewy bodies (LB), Lewy neurites, and other pathological aggregates in Parkinson's disease and synucleinopathies. However, the precise role of these PTM in pathology formation, neurodegeneration, and pathology spreading remains unclear. Here, we systematically investigated the role of post-fibrillization C-terminal aSyn truncations in regulating uptake, processing, seeding, and LB-like inclusion formation using a neuronal seeding model that recapitulates LB formation and neurodegeneration. We show that C-terminal cleavage of aSyn fibrils occurs rapidly post exogenous fibril internalization and during intracellular LB-like inclusion formation. Blocking cleavage of internalized fibrils does not affect seeding, but inhibiting enzymes such as calpains 1 and 2 alters LB-like inclusion formation. We show that C-terminal truncations, along with other PTMs, regulate fibril interactome remodeling, shortening, lateral association, and packing. These findings reveal distinct roles of C-terminal truncations at different aggregation stages on the pathway to LB formation, highlighting the need for consideration of stage‑specific strategies to target aSyn proteolytic cleavages.
Authors
- Martin Citron (ORCID: https://orcid.org/0000-0001-6893-8204)
- Jonathan Ricci (ORCID: https://orcid.org/0000-0002-1326-166X)
- Melek Firat Altay (ORCID: https://orcid.org/0000-0002-8174-5631)
- Georges Mairet‐Coello
- Patrick Downey
- Nadine Ait‐Bouziad (ORCID: https://orcid.org/0000-0003-3182-4179)
- Salvatore Novello (ORCID: https://orcid.org/0000-0003-2157-1358)
- Richard Wade‐Martins (ORCID: https://orcid.org/0000-0001-6691-580X)
- Yllza Jasiqi (ORCID: https://orcid.org/0000-0001-9902-2362)
- Romain Hamelin (ORCID: https://orcid.org/0000-0001-8017-1499)
- Niran Maharjan (ORCID: https://orcid.org/0000-0002-2640-982X)
- Somanath Jagannath
- Galina Limorenko (ORCID: https://orcid.org/0000-0002-6319-0257)
- Anne-Laure Mahul-Mellier
- Graham Knott (ORCID: https://orcid.org/0000-0002-2956-9052)
- Janice L. Holton (ORCID: https://orcid.org/0000-0002-3882-5249)
- Caroline Haikal (ORCID: https://orcid.org/0000-0002-9066-5940)
- Catherine Strand
- Siv Vingill (ORCID: https://orcid.org/0000-0003-4091-7764)
- Laura Weerens
- Anass Chiki (ORCID: https://orcid.org/0000-0002-5675-9644)
- Marie Croisier
- Jiayi Li (ORCID: https://orcid.org/0000-0002-7770-7376)
- Hilal A. Lashuel (ORCID: https://orcid.org/0000-0002-3737-1054)
- Anne Michel
Institutions
- Lund University (SE)
- Cornell University (US)
- University of Oxford (GB)
- Stanford Medicine (US)
- National Hospital for Neurology and Neurosurgery (GB)
- Weill Cornell Medical College in Qatar (QA)
- Weill Cornell Medicine (US)
- University College London (GB)
- École Polytechnique Fédérale de Lausanne (CH)
- UCB Pharma (Belgium) (BE)
- China Medical University (CN)
Publication Details
- Journal
- npj Parkinson s Disease
- Published
- 2025-08-26
- DOI
- https://doi.org/10.1038/s41531-025-01084-y
- Citations
- 3
- Primary Topic
- Parkinson's Disease Mechanisms and Treatments
- Type
- article
- Field-Weighted Citation Impact
- 4.17
Funders
- UCB
- Multiple System Atrophy Trust
- EU Joint Programme – Neurodegenerative Disease Research
- Multiple System Atrophy Coalition
- National Institute for Health and Care Research
- University College London
- École Polytechnique Fédérale de Lausanne
- National Natural Science Foundation of China
- Vetenskapsrådet
- Koning Boudewijnstichting
- Medical Research Council
- Reta Lila Weston Institute of Neurological Studies, UCL Queen Square Institute of Neurology,University College London