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Atomic view of a toxic amyloid small oligomer.

ABSTRACT: Amyloid diseases, including Alzheimer's, Parkinson's, and the prion conditions, are each associated with a particular protein in fibrillar form. These amyloid fibrils were long suspected to be the disease agents, but evidence suggests that smaller, often transient and polymorphic oligomers are the toxic entities. Here, we identify a segment of the amyloid-forming protein ?B crystallin, which forms an oligomeric complex exhibiting properties of other amyloid oligomers: ?-sheet-rich structure, cytotoxicity, and recognition by an oligomer-specific antibody. The x-ray-derived atomic structure of the oligomer reveals a cylindrical barrel, formed from six antiparallel protein strands, that we term a cylindrin. The cylindrin structure is compatible with a sequence segment from the ?-amyloid protein of Alzheimer's disease. Cylindrins offer models for the hitherto elusive structures of amyloid oligomers.

SUBMITTER: Laganowsky A

PROVIDER: S-EPMC3959867 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Atomic view of a toxic amyloid small oligomer.

Laganowsky Arthur A Liu Cong C Sawaya Michael R MR Whitelegge Julian P JP Park Jiyong J Zhao Minglei M Pensalfini Anna A Soriaga Angela B AB Landau Meytal M Teng Poh K PK Cascio Duilio D Glabe Charles C Eisenberg David D

Science (New York, N.Y.) 20120301 6073

Amyloid diseases, including Alzheimer's, Parkinson's, and the prion conditions, are each associated with a particular protein in fibrillar form. These amyloid fibrils were long suspected to be the disease agents, but evidence suggests that smaller, often transient and polymorphic oligomers are the toxic entities. Here, we identify a segment of the amyloid-forming protein αB crystallin, which forms an oligomeric complex exhibiting properties of other amyloid oligomers: β-sheet-rich structure, cyt ...[more]

PMID: 22403391

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