FcαRI binding at the IgA1 C_H2-C_H3 interface induces long-range conformational changes that are transmitted to the hinge region.

ABSTRACT: IgA effector functions include proinflammatory immune responses triggered upon clustering of the IgA-specific receptor, FcαRI, by IgA immune complexes. FcαRI binds to the IgA1-Fc domain (Fcα) at the C_H2-C_H3 junction and, except for C_H2 L257 and L258, all side-chain contacts are contributed by the C_H3 domain. In this study, we used experimental and computational approaches to elucidate energetic and conformational aspects of FcαRI binding to IgA. The energetic contribution of each IgA residue in the binding interface was assessed by alanine-scanning mutagenesis and equilibrium surface plasmon resonance (SPR). As expected, hydrophobic residues central to the binding site have strong energetic contributions to the FcαRI:Fcα interaction. Surprisingly

SUBMITTER: Posgai MT 

PROVIDER: S-EPMC6156678 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature