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Updated: Jun 10, 2026
05:48
Rapid Generation of Amyloid from Native Proteins In vitro
Published on: December 5, 2013
Amyloid fibril formation by human stefins: Structure, mechanism & putative functions
Eva Zerovnik1, Rosemary A Staniforth, Dušan Turk
1Department of Biochemistry, Molecular and Structural Biology, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia. eva.zerovnik@ijs.si
Biochimie
|August 6, 2010
Summary
This review details in vitro studies of human stefin A and B protein aggregation into amyloid fibrils. Key findings include domain-swapping in stefins and the role of proline isomerization in fibril formation, with implications for Alzheimer's disease.
Area of Science:
- Biochemistry
- Structural Biology
- Neuroscience
Background:
- Protein aggregation into amyloid fibrils is implicated in various diseases, yet mechanisms remain unclear.
- Human stefins A and B are studied for their roles in oligomerization and amyloid fibril formation.
- Domain-swapping is a common feature in stefins and other amyloidogenic proteins.
Purpose of the Study:
- To review in vitro studies on human stefin A and B oligomerization and amyloid fibril formation.
- To elucidate the structural and mechanistic properties of stefin amyloidogenesis.
- To explore the interaction of stefin B with amyloid-beta peptide and its cellular aggregation propensity.
Main Methods:
- In vitro studies of oligomerization and amyloid fibril formation.
- Determination of 3D structures of stefin A dimer and stefin B tetramer.
- Analysis of nucleation and fibril elongation kinetics, including activation energies.
- Investigation of prefibrillar oligomer toxicity and interaction with phospholipids.
- In vitro and cellular studies of stefin B interaction with amyloid-beta peptide.
Main Results:
- Specific properties of human stefin B prefibrillar oligomers and amyloid fibrils were identified.
- The 3D structure of a stefin B tetramer, formed by two domain-swapped dimers, was determined.
- Proline isomerization, particularly at Pro 74, is crucial for stefin B fibril formation.
- Prefibrillar oligomer toxicity correlates with their interaction with acidic phospholipids.
- Stefin B interacts specifically with amyloid-beta peptide oligomers in vitro and in cells.
- Certain stefin B variants and mutants (R68X, Y31, G4R) show increased aggregation in cells.
Conclusions:
- Domain-swapping and proline isomerization are key features in stefin amyloidogenesis.
- Stefin B's interaction with amyloid-beta peptide suggests a role in Alzheimer's disease pathogenesis.
- Cellular aggregation of stefin B variants highlights their disease relevance.
- Understanding stefin aggregation provides insights into general amyloid formation mechanisms.
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