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Mechanistic basis for the recognition of laminin-511 by ?6?1 integrin.

ABSTRACT: Laminins regulate diverse cellular functions through interaction with integrins. Two regions of laminins-three laminin globular domains of the ? chain (LG1-3) and the carboxyl-terminal tail of the ? chain (?-tail)-are required for integrin binding, but it remains unclear how the ?-tail contributes to the binding. We determined the crystal structure of the integrin binding fragment of laminin-511, showing that the ?-tail extends to the bottom face of LG1-3. Electron microscopic imaging combined with biochemical analyses showed that integrin binds to the bottom face of LG1-3 with the ?1-tail apposed to the metal ion-dependent adhesion site (MIDAS) of integrin ?1. These findings are consistent with a model in which the ?-tail coordinates the metal ion in the MIDAS through its Glu residue.

SUBMITTER: Takizawa M

PROVIDER: S-EPMC5580876 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Mechanistic basis for the recognition of laminin-511 by α6β1 integrin.

Takizawa Mamoru M Arimori Takao T Taniguchi Yukimasa Y Kitago Yu Y Yamashita Erika E Takagi Junichi J Sekiguchi Kiyotoshi K

Science advances 20170901 9

Laminins regulate diverse cellular functions through interaction with integrins. Two regions of laminins-three laminin globular domains of the α chain (LG1-3) and the carboxyl-terminal tail of the γ chain (γ-tail)-are required for integrin binding, but it remains unclear how the γ-tail contributes to the binding. We determined the crystal structure of the integrin binding fragment of laminin-511, showing that the γ-tail extends to the bottom face of LG1-3. Electron microscopic imaging combined w ...[more]

PMID: 28879238

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