Receptor-G protein coupling is established by a potential conformational switch in the beta gamma complex.

• DOI: 10.1073/pnas.92.20.9102
• Publication Date: 2006-05-31T13:21:01Z
• Authors: O Kisselev; A Pronin; M Ermolaeva; N Gautam
• Keywords: 0301 basic medicine; Rhodopsin; Macromolecular Substances; Protein Conformation; Immunoblotting; Molecular Sequence Data; Receptors, Cell Surface; Coturnix; Transfection; Antibodies; Recombinant Proteins; Cell Line; Models, Structural; Kinetics; 03 medical and health sciences; GTP-Binding Proteins; Animals; Amino Acid Sequence; Transducin; Peptides; Protein Binding

Receptor-G protein interaction is characterized by cycles of association and dissociation. We present evidence which indicates that during receptor-G protein interaction, the C-terminal tail of the G protein gamma subunit, which is masked in the beta gamma complex, is exposed and establishes high-affinity contact with the receptor. This potential conformational switch provides a mechanism to regulate receptor-G protein coupling. This switch may also be significant for the role of the beta gamma complex in regulation of effector function.