PMID: 24187131 , Related PDB id: 2M32

Authors:

Chin YK, Headey SJ, Mohanty B, Patil R, McEwan PA, Swarbrick JD, Mulhern TD, Emsley J, Simpson JS, Scanlon MJ

Title:

The structure of integrin alpha1I domain in complex with a collagen-mimetic peptide.

Journal:

J Biol Chem. 2013 Dec 27;288(52):36796-809. doi: 10.1074/jbc.M113.480251. Epub, 2013 Nov 1.

Abstract:

We have determined the structure of the human integrin alpha1I domain bound to a triple-helical collagen peptide. The structure of the alpha1I-peptide complex was investigated using data from NMR, small angle x-ray scattering, and size exclusion chromatography that were used to generate and validate a model of the complex using the data-driven docking program, HADDOCK (High Ambiguity Driven Biomolecular Docking). The structure revealed that the alpha1I domain undergoes a major conformational change upon binding of the collagen peptide. This involves a large movement in the C-terminal helix of the alphaI domain that has been suggested to be the mechanism by which signals are propagated in the intact integrin receptor. The structure suggests a basis for the different binding selectivity observed for the alpha1I and alpha2I domains. Mutational data identify residues that contribute to the conformational change observed. Furthermore, small angle x-ray scattering data suggest that at low collagen peptide concentrations the complex exists in equilibrium between a 1:1 and 2:1 alpha1I-peptide complex.