title: Structure of the rgRGS domain of p115RhoGEF.
abstract: p115RhoGEF, a guanine nucleotide exchange factor for Rho GTPase, is also a GTPase activating protein (GAP) for G(12) and G(13) heterotrimeric G alpha subunits. Near its N-terminus, p115RhoGEF contains a domain (rgRGS) with remote sequence identity to RGS (regulators of G protein signaling) domains. The rgRGS domain is necessary but not sufficient for the GAP activity of p115RhoGEF. The 1.9 A resolution crystal structure of the rgRGS domain shows structural similarity to RGS domains but possesses a C-terminal extension that folds into a layer of helices that pack against the hydrophobic core of the domain. Mutagenesis experiments show that rgRGS may form interactions with G alpha(13) that are analogous to those in complexes of RGS proteins with their G alpha substrates.
authors.affiliation: Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas 75390-9050, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.forename: C D
authors.initials: CD
authors.lastname: Wells
authors.forename: P C
authors.initials: PC
authors.lastname: Sternweis
authors.forename: S R
authors.initials: SR
authors.lastname: Sprang
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D020662:Guanine Nucleotide Exchange Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020962:Heterotrimeric GTP-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D064067:Rho Guanine Nucleotide Exchange Factors; D016415:Sequence Alignment
chemical_list: D020662:Guanine Nucleotide Exchange Factors; D010446:Peptide Fragments; D021122:Protein Subunits; D064067:Rho Guanine Nucleotide Exchange Factors; D020962:Heterotrimeric GTP-Binding Proteins