GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:10489445

From GONUTS
Jump to: navigation, search
Citation

Longenecker, K, Read, P, Derewenda, U, Dauter, Z, Liu, X, Garrard, S, Walker, L, Somlyo, AV, Nakamoto, RK, Somlyo, AP and Derewenda, ZS (1999) How RhoGDI binds Rho. Acta Crystallogr. D Biol. Crystallogr. 55:1503-15

Abstract

Like all Rho (Ras homology) GTPases, RhoA functions as a molecular switch in cell signaling, alternating between GTP- and GDP-bound states, with its biologically inactive GDP-bound form maintained as a cytosolic complex with RhoGDI (guanine nucleotide-exchange inhibitor). The crystal structures of RhoA-GDP and of the C-terminal immunoglobulin-like domain of RhoGDI (residues 67-203) are known, but the mechanism by which the two proteins interact is not known. The functional human RhoA-RhoGDI complex has been expressed in yeast and crystallized (P6(5)22, unit-cell parameters a = b = 139, c = 253 A, two complexes in the asymmetric unit). Although diffraction from these crystals extends to 3.5 A and is highly anisotropic, the experimentally phased (MAD plus MIR) electron-density map was adequate to reveal the mutual disposition of the two molecules. The result was validated by molecular-replacement calculations when data were corrected for anisotropy. Furthermore, the N-terminus of RhoGDI (the region involved in inhibition of nucleotide exchange) can be identified in the electron-density map: it is bound to the switch I and switch II regions of RhoA, occluding an epitope which binds Dbl-like nucleotide-exchange factors. The entrance of the hydrophobic pocket of RhoGDI is 25 A from the last residue in the RhoA model, with its C-terminus oriented to accommodate the geranylgeranyl group without conformational change in RhoA.

Links

PubMed

Keywords

Binding Sites; Crystallography, X-Ray; Cytosol/metabolism; Dimerization; GTP Phosphohydrolases/metabolism; GTP-Binding Proteins/biosynthesis; GTP-Binding Proteins/chemistry; GTP-Binding Proteins/genetics; GTP-Binding Proteins/metabolism; Guanine Nucleotide Dissociation Inhibitors; Humans; Oligopeptides/metabolism; Protein Binding; Protein Conformation; Protein Structure, Secondary; Reproducibility of Results; Saccharomyces cerevisiae/genetics; Saccharomyces cerevisiae/metabolism; rho Guanine Nucleotide Dissociation Inhibitor alpha; rho-Specific Guanine Nucleotide Dissociation Inhibitors; rhoA GTP-Binding Protein

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

HUMAN:GDIR1

enables

GO:0005515: protein binding

ECO:0000353: physical interaction evidence used in manual assertion

UniProtKB:P61586

F

Seeded From UniProt

complete

HUMAN:RHOA

enables

GO:0005515: protein binding

ECO:0000353: physical interaction evidence used in manual assertion

UniProtKB:P52565

F

Seeded From UniProt

complete


See also

References

See Help:References for how to manage references in GONUTS.