Conformational analysis of the Galpha(s) protein C-terminal region.

The C-terminal domain of the heterotrimeric G protein a-subunits plays a key role in selective activation of G proteins by their cognate receptors. Several C-terminal fragments of Galpha(s) (from 11 to 21 residues) were recently synthesized. The ability of these peptides to stimulate agonist binding was found to be related to their size.