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An amyloid-forming segment of beta2-microglobulin suggests a molecular model for the fibril.

ABSTRACT: In humans suffering from dialysis-related amyloidosis, the protein beta2-microglobulin (beta2M) is deposited as an amyloid; however, an amyloid of beta2M is unknown in mice. beta2M sequences from human and mouse are 70% identical, but there is a seven-residue peptide in which six residues differ. This peptide from human beta2M forms amyloid in vitro, whereas the mouse peptide does not. Substitution of the human peptide for its counterpart in the mouse sequence results in the formation of amyloid in vitro. These results show that a seven-residue segment of human beta2M is sufficient to convert beta2M to the amyloid state, and that specific residue interactions are crucial to the conversion. These observations are consistent with a proposed Zipper-spine model for beta2M amyloid, in which the spine of the fibril consists of an anhydrous beta-sheet.

SUBMITTER: Ivanova MI

PROVIDER: S-EPMC489978 | biostudies-literature | 2004 Jul

REPOSITORIES: biostudies-literature

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An amyloid-forming segment of beta2-microglobulin suggests a molecular model for the fibril.

Ivanova Magdalena I MI Sawaya Michael R MR Gingery Mari M Attinger Antoine A Eisenberg David D

Proceedings of the National Academy of Sciences of the United States of America 20040712 29

In humans suffering from dialysis-related amyloidosis, the protein beta2-microglobulin (beta2M) is deposited as an amyloid; however, an amyloid of beta2M is unknown in mice. beta2M sequences from human and mouse are 70% identical, but there is a seven-residue peptide in which six residues differ. This peptide from human beta2M forms amyloid in vitro, whereas the mouse peptide does not. Substitution of the human peptide for its counterpart in the mouse sequence results in the formation of amyloid ...[more]

PMID: 15249659

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