Format

Send to

Choose Destination
Biochem Biophys Res Commun. 2019 Jan 15;508(3):729-734. doi: 10.1016/j.bbrc.2018.11.200. Epub 2018 Dec 6.

Biochemical and morphological classification of disease-associated alpha-synuclein mutants aggregates.

Author information

1
Laboratory of Structural Neuropathology, Doshisha University Graduate School of Brain Science, 1-3 Miyakodanitatara, Kyotanabe-shi, Kyoto, 610-0394, Japan.
2
Laboratory of Structural Neuropathology, Doshisha University Graduate School of Brain Science, 1-3 Miyakodanitatara, Kyotanabe-shi, Kyoto, 610-0394, Japan. Electronic address: toyamana@mail.doshisha.ac.jp.
3
Laboratory for Mechanistic Chemistry of Biomolecules, Department of Chemistry, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama, 223-8522, Japan.
4
Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka, 567-0047, Japan.
5
Laboratory of Structural Neuropathology, Doshisha University Graduate School of Brain Science, 1-3 Miyakodanitatara, Kyotanabe-shi, Kyoto, 610-0394, Japan. Electronic address: nnukina@mail.doshisha.ac.jp.

Abstract

Alpha-synuclein (a-syn) aggregation in brain is implicated in several synucleinopathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Until date, at least six disease-associated mutations in a-syn (namely A30P, E46K, H50Q, G51D, A53T, and A53E) are known to cause dominantly inherited familial forms of synucleinopathies. Previous studies using recombinant proteins have reported that a subset of disease-associated mutants show higher aggregation propensities and form spectroscopically distinguishable aggregates compared to wild-type (WT). However, morphological and biochemical comparison of the aggregates for all disease-associated a-syn mutants have not yet been performed. In this study, we performed electron microscopic examination, guanidinium hydrochloride (GdnHCl) denaturation, and protease digestion to classify the aggregates from their respective point mutations. Using electron microscopy we observed variations of amyloid fibrillar morphologies among the aggregates of a-syn mutants, mainly categorized into two groups: twisted fibrils observed for both WT and E46K while straight fibrils for the other mutants. GdnHCl denaturation experiments revealed the a-syn mutants except for E46K were more resistant than WT against the denaturation. Mass spectrometry analysis of protease-treated aggregates showed a variety of protease-resistant cores, which may correspond to their morphological properties. The difference of their properties could be implicated in the clinicopathological difference of synucleinopathies with those mutations.

KEYWORDS:

Alpha-synuclein; Disease-associated mutation; Protein aggregation; Synucleinopathy

PMID:
30528390
DOI:
10.1016/j.bbrc.2018.11.200

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center