Synaptic vesicle mimics affect the aggregation of wild-type and A53T α-synuclein variants differently albeit similar membrane affinity. Issue 2 (30th September 2019)

• Record Type: Journal Article
• Authors: Rocha, Sandra; Kumar, Ranjeet; Horvath, Istvan; Wittung-Stafshede, Pernilla
• Editors: Daggett, Valerie
• Is Part Of: Protein engineering, design & selection. Volume 32:Issue 2(2019)
• Page Start: 59
• Page End: 66
• Publication Date: 2019-09-30
• Subjects: amyloid fibrils -- kinetic profiles -- membrane-bound α-synuclein -- protein aggregation -- small unilamellar vesicles; Protein engineering -- Periodicals; 660.63
• DOI: 10.1093/protein/gzz021
• Languages: English
• ISSNs: 1741-0126

Abstract

Abstract: α-Synuclein misfolding results in the accumulation of amyloid fibrils in Parkinson's disease. Missense protein mutations (e.g. A53T) have been linked to early onset disease. Although α-synuclein interacts with synaptic vesicles in the brain, it is not clear what role they play in the protein aggregation process. Here, we compare the effect of small unilamellar vesicles (lipid composition similar to synaptic vesicles) on wild-type (WT) and A53T α-synuclein aggregation. Using biophysical techniques, we reveal that binding affinity to the vesicles is similar for the two proteins, and both interact with the helix long axis parallel to the membrane surface. Still, the vesicles affect the aggregation of the variants differently: effects on secondary processes such as fragmentation dominate for WT, whereas for A53T, fibril elongation is mostly affected. We speculate that vesicle interactions with aggregate intermediate species, in addition to monomer binding, vary between WT and A53T, resulting in different consequences for amyloid formation.