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Evidence for a partially folded intermediate in alpha-synuclein fibril formation
1Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, USA.
The Journal of Biological Chemistry
|January 22, 2001
Summary
Investigating alpha-synuclein aggregation, this study reveals that changes in pH and temperature induce a partially folded intermediate. This intermediate is key to the formation of pathological fibrils in neurodegenerative diseases like Parkinson's disease.
Area of Science:
- Neuroscience
- Biochemistry
- Structural Biology
Background:
- Alpha-synuclein protein aggregates form Lewy bodies and neurites, characteristic of Parkinson's disease and related disorders.
- The mechanism by which natively unfolded alpha-synuclein forms ordered fibrils is not well understood.
- Understanding this process is crucial for elucidating the molecular basis of synucleinopathies.
Purpose of the Study:
- To investigate the effects of pH and temperature on the structural properties of alpha-synuclein.
- To determine how these factors influence the kinetics of alpha-synuclein fibrillation.
- To propose a model for alpha-synuclein aggregation.
Main Methods:
- Studied human recombinant alpha-synuclein.
- Manipulated pH and temperature conditions.
- Analyzed structural changes and fibrillation rates.
Main Results:
- Decreased pH or increased temperature induced a partially folded conformation in alpha-synuclein.
- This partially folded intermediate was strongly correlated with accelerated fibril formation.
- Identified a critical intermediate in the aggregation pathway.
Conclusions:
- A conformational transformation into a partially folded state is an early and critical step in alpha-synuclein fibrillation.
- Environmental factors like pH and temperature can trigger this aggregation-competent intermediate.
- This finding provides a molecular mechanism for alpha-synuclein fibril formation in neurodegenerative diseases.
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