Ligand- and cation-induced structural alterations of the leukocyte integrin LFA-1.

ABSTRACT: In αI integrins, including leukocyte function-associated antigen 1 (LFA-1), ligand-binding function is delegated to the αI domain, requiring extra steps in the relay of signals that activate ligand binding and coordinate it with cytoplasmic signals. Crystal structures reveal great variation in orientation between the αI domain and the remainder of the integrin head. Here, we investigated the mechanisms involved in signal relay to the αI domain, including whether binding of the ligand intercellular adhesion molecule-1 (ICAM-1) to the αI domain is linked to headpiece opening and engenders a preferred αI domain orientation. Using small-angle X-ray scattering and negative-stain EM, we define structures of ICAM-1, LFA-1, and their complex, and the effect of activation by Mn²⁺ Headpie

SUBMITTER: Sen M 

PROVIDER: S-EPMC5925802 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature