Unraveling amyloid formation paths of Parkinson's disease protein alpha-synuclein triggered by anionic vesicles
Journal article, 2017

Amyloid formation of the synaptic brain protein alpha-synuclein (alpha S) is related to degeneration of dopaminergic neurons in Parkinson's disease patients. aS is thought to function in vesicle transport and fusion and it binds strongly to negatively charged vesicles in vitro. Here we combined circular dichroism, fluorescence and imaging methods in vitro to characterize the interaction of alpha S with negatively charged vesicles of DOPS (1,2-dioleoyl-sn-glycero-3-phospho-L-serine, sodium salt) and DOPG (1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol), sodium salt) and the consequences of such interactions on alpha S amyloid formation. We found that lipid head-group chemistry modulates alpha S interactions and also affects amyloid fiber formation. During the course of the experiments, we made the unexpected discovery that pre-formed alpha S oligomers, typically present in a small amount in the alpha S starting material, acted as templates for linear growth of anomalous amyloid fibers in the presence of vesicles. At the same time, the remaining alpha S monomers were restricted from vesicle-mediated nucleation of amyloid fibers. Although not a dominant process in bulk experiments, this hidden alpha S aggregation pathway may be of importance in vivo.

mutation

fibrillation

fibrillogenesis

aggregation

membrane interactions

packing defects

lipid vesicles

phospholipid-binding

states

solution nmr-spectroscopy

Author

Juris Kiskis

Chalmers, Biology and Biological Engineering, Food and Nutrition Science

Istvan Horvath

Chalmers, Biology and Biological Engineering, Chemical Biology

Pernilla Wittung Stafshede

Chalmers, Biology and Biological Engineering, Chemical Biology

Sandra Rocha

Chalmers, Biology and Biological Engineering, Chemical Biology

Quarterly Reviews of Biophysics

0033-5835 (ISSN) 1469-8994 (eISSN)

Vol. 50 1-9

Subject Categories

Biophysics

DOI

10.1017/s0033583517000026

PubMed

29233215

More information

Latest update

9/25/2018