A pivotal role for a conserved bulky residue at the α1-helix of the αI integrin domain in ligand binding.

ABSTRACT: The ligand-binding βI and αI domains of integrin are the best-studied von Willebrand factor A domains undergoing significant conformational changes for affinity regulation. In both βI and αI domains, the α1- and α7-helixes work in concert to shift the metal-ion-dependent adhesion site between the resting and active states. An absolutely conserved Gly in the middle of the α1-helix of βI helps maintain the resting βI conformation, whereas the homologous position in the αI α1-helix contains a conserved Phe. A functional role of this Phe is structurally unpredictable. Using α_Lβ₂ integrin as a model, we found that the residue volume at the Phe position in the α1-helix is critical for α_Lβ₂ activation because trimming the Phe by small amino acid substit

SUBMITTER: Wang Z 

PROVIDER: S-EPMC5733610 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature