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Crystal Structure of the Heterotrimeric Integrin-Binding Region of Laminin-111.

ABSTRACT: Laminins are cell-adhesive glycoproteins that are essential for basement membrane assembly and function. Integrins are important laminin receptors, but their binding site on the heterotrimeric laminins is poorly defined structurally. We report the crystal structure at 2.13 Å resolution of a minimal integrin-binding fragment of mouse laminin-111, consisting of ?50 residues of ?1?1?1 coiled coil and the first three laminin G-like (LG) domains of the ?1 chain. The LG domains adopt a triangular arrangement, with the C terminus of the coiled coil situated between LG1 and LG2. The critical integrin-binding glutamic acid residue in the ?1 chain tail is surface exposed and predicted to bind to the metal ion-dependent adhesion site in the integrin ?1 subunit. Additional contacts to the integrin are likely to be made by the LG1 and LG2 surfaces adjacent to the ?1 chain tail, which are notably conserved and free of obstructing glycans.

SUBMITTER: Pulido D

PROVIDER: S-EPMC5343747 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Crystal Structure of the Heterotrimeric Integrin-Binding Region of Laminin-111.

Pulido David D Hussain Sadaf-Ahmahni SA Hohenester Erhard E

Structure (London, England : 1993) 20170126 3

Laminins are cell-adhesive glycoproteins that are essential for basement membrane assembly and function. Integrins are important laminin receptors, but their binding site on the heterotrimeric laminins is poorly defined structurally. We report the crystal structure at 2.13 Å resolution of a minimal integrin-binding fragment of mouse laminin-111, consisting of ∼50 residues of α1β1γ1 coiled coil and the first three laminin G-like (LG) domains of the α1 chain. The LG domains adopt a triangular arra ...[more]

PMID: 28132784

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