Amyloid: Morphology and Toxicity
| Autor: | Anders Olofsson, Erik Lundgren, Johan Ostman |
|---|---|
| Rok vydání: | 2002 |
| Předmět: |
Amyloid
Protein Folding Morphology (linguistics) Clinical Biochemistry Mutant Apoptosis macromolecular substances Microscopy Atomic Force Fibril medicine Humans Prealbumin Cytotoxicity biology Amyloidosis Biochemistry (medical) General Medicine medicine.disease In vitro Transthyretin Biochemistry Mutation Biophysics biology.protein HeLa Cells Protein Binding |
| Zdroj: | Clinical Chemistry and Laboratory Medicine. 40 |
| ISSN: | 1434-6621 |
| Popis: | We have expressed transthyretin (TTR) mutants which have significantly destabilised tetramers that aggregate into amyloid fibrils via a series of intermediates. We used atomic force microscopy to follow the morphology of aggregates during fibril formation. Initially, amorphous aggregates are formed that subsequently mature into fibrillar structures. This observation is interpreted as an optimisation of beta-strand registers. The rate of aggregation and maturation is highly temperature-dependent suggesting that entropic forces significantly contribute to stability. In addition, we identified a correlation between the presence of early formed aggregates of TTR and cytotoxicity. The toxic response was mediated via an apoptotic mechanism. The fact that early formed amorphous aggregates, but not more mature fibrils, exert a toxic response suggests that the rate of fibril formation may be a critical parameter. We propose that a slow rate of aggregation facilitates an increased concentration of a toxic intermediate. |
| Databáze: | OpenAIRE |
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