Regulation of T cell receptor activation by dynamic membrane binding of the CD3epsilon cytoplasmic tyrosine-based motif.

ABSTRACT: Many immune system receptors signal through cytoplasmic tyrosine-based motifs (ITAMs), but how receptor ligation results in ITAM phosphorylation remains unknown. Live-cell imaging studies showed a close interaction of the CD3epsilon cytoplasmic domain of the T cell receptor (TCR) with the plasma membrane through fluorescence resonance energy transfer between a C-terminal fluorescent protein and a membrane fluorophore. Electrostatic interactions between basic CD3epsilon residues and acidic phospholipids enriched in the inner leaflet of the plasma membrane were required for binding. The nuclear magnetic resonance structure of the lipid-bound state of this cytoplasmic domain revealed deep insertion of the two key tyrosines into the hydrophobic core of the lipid bilayer. Receptor ligation thus

SUBMITTER: Xu C 

PROVIDER: S-EPMC2597348 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature