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Analysis of β-Amyloid-induced Abnormalities on Fibrin Clot Structure by Spectroscopy and Scanning Electron Microscopy
Published on: November 30, 2018
Branching in amyloid fibril growth
Christian Beyschau Andersen1, Hisashi Yagi, Mauro Manno
1Protein Structure and Biophysics, Novo Nordisk A/S, DK-2760 Måløv, Denmark.
Biophysical Journal
|February 17, 2009
Summary
Amyloid fibrils can multiply through branching, a novel real-time observation in glucagon fibrils. This branching mechanism differs from Abeta(1-40) fibril growth, impacting overall fibrillation kinetics and highlighting fibril-dependent nucleation.
Area of Science:
- Biochemistry
- Biophysics
- Molecular Biology
Background:
- Amyloid fibrils are protein aggregates implicated in various diseases.
- Understanding fibril growth and multiplication mechanisms is crucial for disease intervention.
Purpose of the Study:
- To elucidate the mechanisms of amyloid fibril growth and multiplication.
- To observe fibril growth dynamics at a single-fibril level in real-time.
Main Methods:
- Real-time single-fibril observation.
- Light scattering kinetics analysis.
- Utilized glucagon and Abeta(1-40) as model systems.
Main Results:
- Observed real-time branching of glucagon fibrils, a novel finding.
- Glucagon fibril branching occurred at a preferred angle (35-40 degrees) and not at the fibril tip.
- Abeta(1-40) fibrils grew exclusively by elongation.
- Fibrillation kinetics differed between glucagon and Abeta(1-40), supporting distinct growth mechanisms.
Conclusions:
- Amyloid fibril growth can involve branching, generating new fibril ends.
- Branching significantly influences fibrillation kinetics compared to elongation alone.
- Fibril-dependent nucleation plays a central role in amyloid fibril growth dynamics.
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