A new approach to producing functional G alpha subunits yields the activated and deactivated structures of G alpha(12/13) proteins.

ABSTRACT: The oncogenic G(12/13) subfamily of heterotrimeric G proteins transduces extracellular signals that regulate the actin cytoskeleton, cell cycle progression, and gene transcription. Previously, structural analyses of fully functional G alpha(12/13) subunits have been hindered by insufficient amounts of homogeneous, functional protein. Herein, we report that substitution of the N-terminal helix of G alpha(i1) for the corresponding region of G alpha12 or G alpha13 generated soluble chimeric subunits (G alpha(i/12) and G alpha(i/13)) that could be purified in sufficient amounts for crystallographic studies. Each chimera bound guanine nucleotides, G betagamma subunits, and effector proteins and exhibited GAP responses to p115RhoGEF and leukemia-associated RhoGEF. Like their wild-type counterpar

SUBMITTER: Kreutz B 

PROVIDER: S-EPMC2688741 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature