A Targetable N-Terminal Motif Orchestrates α-Synuclein Oligomer-to-Fibril Conversion.
J Am Chem Soc
; 146(18): 12702-12711, 2024 May 08.
Article
em En
| MEDLINE
| ID: mdl-38683963
ABSTRACT
Oligomeric species populated during α-synuclein aggregation are considered key drivers of neurodegeneration in Parkinson's disease. However, the development of oligomer-targeting therapeutics is constrained by our limited knowledge of their structure and the molecular determinants driving their conversion to fibrils. Phenol-soluble modulin α3 (PSMα3) is a nanomolar peptide binder of α-synuclein oligomers that inhibits aggregation by blocking oligomer-to-fibril conversion. Here, we investigate the binding of PSMα3 to α-synuclein oligomers to discover the mechanistic basis of this protective activity. We find that PSMα3 selectively targets an α-synuclein N-terminal motif (residues 36-61) that populates a distinct conformation in the mono- and oligomeric states. This α-synuclein region plays a pivotal role in oligomer-to-fibril conversion as its absence renders the central NAC domain insufficient to prompt this structural transition. The hereditary mutation G51D, associated with early onset Parkinson's disease, causes a conformational fluctuation in this region, leading to delayed oligomer-to-fibril conversion and an accumulation of oligomers that are resistant to remodeling by molecular chaperones. Overall, our findings unveil a new targetable region in α-synuclein oligomers, advance our comprehension of oligomer-to-amyloid fibril conversion, and reveal a new facet of α-synuclein pathogenic mutations.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Alfa-Sinucleína
Limite:
Humans
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Espanha