A common site of the Fc receptor γ subunit interacts with the unrelated immunoreceptors FcαRI and FcεRI

Abstract

The transmembrane (TM) region of the Fc receptor-γ (FcRγ) chain is responsible for the association of this ubiquitous signal transduction subunit with many immunoreceptor ligand binding chains, making FcRγ key to a number of leukocyte activities in immunity and disease. Some receptors contain a TM arginine residue that interacts with Asp-11 of the FcRγ subunit, but otherwise the molecular basis for the FcRγ subunit interactions is largely unknown. This study reports residues in the TM region of the FcRγ subunit are important for association with the high affinity IgE receptor FcεRI and a leukocyte receptor cluster member, the IgA receptor FcαRI. FcRγ residue Leu-21 was essential for surface ..