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Domain metastability: a molecular basis for immunoglobulin deposition?

ABSTRACT: We present the crystal structure of an immunoglobulin light-chain-like domain, CTLA-4, as a strand-swapped dimer displaying cis-trans proline isomerisation and native-like hydrogen bonding. We also show that CTLA-4 can form amyloid-like fibres and amorphous deposits explainable by the same strand swapping. Our results suggest a molecular basis for the pathological aggregation of immunoglobulin domains and why amyloid-like fibres are more often composed of homologous rather than heterologous subunits.

SUBMITTER: Sonnen AF

PROVIDER: S-EPMC2954335 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Domain metastability: a molecular basis for immunoglobulin deposition?

Sonnen Andreas F-P AF Yu Chao C Evans Edward J EJ Stuart David I DI Davis Simon J SJ Gilbert Robert J C RJ

Journal of molecular biology 20100413 2

We present the crystal structure of an immunoglobulin light-chain-like domain, CTLA-4, as a strand-swapped dimer displaying cis-trans proline isomerisation and native-like hydrogen bonding. We also show that CTLA-4 can form amyloid-like fibres and amorphous deposits explainable by the same strand swapping. Our results suggest a molecular basis for the pathological aggregation of immunoglobulin domains and why amyloid-like fibres are more often composed of homologous rather than heterologous subu ...[more]

PMID: 20394753

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