scholarly journals Alpha-synuclein stepwise aggregation reveals features of an early onset mutation in Parkinson’s disease

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Guilherme A. P. de Oliveira ◽  
Jerson L. Silva
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Early Onset ◽  
Point Mutations ◽  
Alpha Synuclein ◽  
Amyloid Formation ◽  
Wild Type ◽  
Cryo Electron Microscopy ◽  
Familial Parkinson’S Disease ◽  
Direct Detector

Abstract Amyloid formation is a process involving interconverting protein species and results in toxic oligomers and fibrils. Aggregated alpha-synuclein (αS) participates in neurodegenerative maladies, but a closer understanding of the early αS polymerization stages and polymorphism of heritable αS variants is sparse still. Here, we distinguished αS oligomer and protofibril interconversions in Thioflavin T polymerization reactions. The results support a hypothesis reconciling the nucleation-polymerization and nucleation-conversion-polymerization models to explain the dissimilar behaviors of wild-type and the A53T mutant. Cryo-electron microscopy with a direct detector shows the polymorphic nature of αS fibrils formed by heritable A30P, E46K, and A53T point mutations. By showing that A53T rapidly nucleates competent species, continuously elongates fibrils in the presence of increasing amounts of seeds, and overcomes wild-type surface requirements for growth, our findings place A53T with features that may explain the early onset of familial Parkinson’s disease cases bearing this mutation.

scholarly journals Familial Parkinson's Disease Mutant E46K α-Synuclein Localizes to Membranous Structures, Forms Aggregates, and Induces Toxicity in Yeast Models

2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Michael Fiske ◽  
Michael White ◽  
Stephanie Valtierra ◽  
Sara Herrera ◽  
Keith Solvang ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Plasma Membrane ◽  
Mutant Form ◽  
Phospholipid Membrane ◽  
Endomembrane System ◽  
Wild Type ◽  
Significant Toxicity ◽  
Familial Parkinson’S Disease

In Parkinson’s disease (PD), midbrain dopaminergic neuronal death is linked to the accumulation of aggregated α-synuclein. The familial PD mutant form of α-synuclein, E46K, has not been thoroughly evaluated yet in an organismal model system. Here, we report that E46K resembled wild-type (WT) α-synuclein in Saccharomyces cerevisiae in that it predominantly localized to the plasma membrane, and it did not induce significant toxicity or accumulation. In contrast, in Schizosaccharomyces pombe, E46K did not associate with the plasma membrane. Instead, in one strain, it extensively aggregated in the cytoplasm and was as toxic as WT. Remarkably, in another strain, E46K extensively associated with the endomembrane system and was more toxic than WT. Our studies recapitulate and extend aggregation and phospholipid membrane association properties of E46K previously observed in vitro and cell culture. Furthermore, it supports the notion that E46K generates toxicity partly due to increased association with endomembrane systems within cells.

scholarly journals Single Molecule FRET Characterization of Oligomers from Alpha-Synuclein Early Onset Parkinson's Disease Mutants

2014 ◽  
Vol 106 (2) ◽  
pp. 269a ◽  
Author(s):  
Laura Tosatto ◽  
Mathew H. Horrocks ◽  
Cremades Nunilo ◽  
Tim Guilliams ◽  
Mauro Dalla Serra ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Single Molecule ◽  
Early Onset ◽  
Alpha Synuclein ◽  
Single Molecule Fret ◽  
Early Onset Parkinson’S Disease

scholarly journals Cryo-EM structure of alpha-synuclein fibrils

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Ricardo Guerrero-Ferreira ◽  
Nicholas MI Taylor ◽  
Daniel Mona ◽  
Philippe Ringler ◽  
Matthias E Lauer ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Lewy Bodies ◽  
Alpha Synuclein ◽  
Diagnosis And Treatment ◽  
Lewy Neurites ◽  
Cryo Electron Microscopy ◽  
High Concentrations ◽  
Hydrophobic Cleft

Parkinson’s disease is a progressive neuropathological disorder that belongs to the class of synucleinopathies, in which the protein alpha-synuclein is found at abnormally high concentrations in affected neurons. Its hallmark are intracellular inclusions called Lewy bodies and Lewy neurites. We here report the structure of cytotoxic alpha-synuclein fibrils (residues 1–121), determined by cryo-electron microscopy at a resolution of 3.4 Å. Two protofilaments form a polar fibril composed of staggered β-strands. The backbone of residues 38 to 95, including the fibril core and the non-amyloid component region, are well resolved in the EM map. Residues 50–57, containing three of the mutation sites associated with familial synucleinopathies, form the interface between the two protofilaments and contribute to fibril stability. A hydrophobic cleft at one end of the fibril may have implications for fibril elongation, and invites for the design of molecules for diagnosis and treatment of synucleinopathies.

scholarly journals Mitochondria interaction networks show altered topological patterns in Parkinson’s disease

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Massimiliano Zanin ◽  
Bruno F. R. Santos ◽  
Paul M. A. Antony ◽  
Clara Berenguer-Escuder ◽  
Simone B. Larsen ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Point Mutations ◽  
Interaction Network ◽  
Critical Dimension ◽  
Alpha Synuclein ◽  
Interaction Networks ◽  
Scale Free ◽  
Midbrain Dopaminergic Neurons ◽  
Highly Correlated

Abstract Mitochondrial dysfunction is linked to pathogenesis of Parkinson’s disease (PD). However, individual mitochondria-based analyses do not show a uniform feature in PD patients. Since mitochondria interact with each other, we hypothesize that PD-related features might exist in topological patterns of mitochondria interaction networks (MINs). Here we show that MINs formed nonclassical scale-free supernetworks in colonic ganglia both from healthy controls and PD patients; however, altered network topological patterns were observed in PD patients. These patterns were highly correlated with PD clinical scores and a machine-learning approach based on the MIN features alone accurately distinguished between patients and controls with an area-under-curve value of 0.989. The MINs of midbrain dopaminergic neurons (mDANs) derived from several genetic PD patients also displayed specific changes. CRISPR/CAS9-based genome correction of alpha-synuclein point mutations reversed the changes in MINs of mDANs. Our organelle-interaction network analysis opens another critical dimension for a deeper characterization of various complex diseases with mitochondrial dysregulation.

Sign in / Sign up

Export Citation Format

Share Document