Consequences of weak interaction of rho GDI with the GTP-bound forms of rho p21 and rac p21
- PMID: 8226937
Consequences of weak interaction of rho GDI with the GTP-bound forms of rho p21 and rac p21
Abstract
rho GDI is an inhibitory GDP/GTP exchange protein for the rho family. Recently, rho GDI has been reported to interact with the GTP-bound form of G25K and rac1 p21 and to inhibit their basal and GTPase-activating protein (GAP)-stimulated GTPase activity. Here, we examined whether rho GDI interacts with the GTP-bound form of rho p21 and rac p21 and inhibits their basal and rho GAP-stimulated GTPase activity, rho GDI interacted with both the GDP- and GTP-bound forms of rhoA p21 and rac1 p21 as estimated by measuring its ability to form a complex with both forms and to inhibit the membrane-binding activity of both forms. The efficiency of rho GDI for interaction with the GTP-bound form was, however, about 10% that for interaction with the GDP-bound form. Moreover, rho GDI inhibited both the basal and rho GAP-stimulated GTPase activity of rhoA p21 and rac1 p21 in a dose-dependent manner. The doses of rho GDI necessary for this action were, however, about 10-fold higher than those necessary for the action to inhibit their GDP/GTP exchange reaction. These results indicate that rho GDI interacts with the GTP-bound form of its substrate small G proteins, as well as with the GDP-bound form, but much less efficiently than with the GDP-bound form.
Similar articles
-
Regulation of morphology by rho p21 and its inhibitory GDP/GTP exchange protein (rho GDI) in Swiss 3T3 cells.J Biol Chem. 1993 Jan 5;268(1):510-5. J Biol Chem. 1993. PMID: 8416955
-
GDP dissociation inhibitor prevents intrinsic and GTPase activating protein-stimulated GTP hydrolysis by the Rac GTP-binding protein.J Biol Chem. 1993 Jan 15;268(2):775-8. J Biol Chem. 1993. PMID: 8419353
-
Purification and characterization from bovine brain cytosol of a novel regulatory protein inhibiting the dissociation of GDP from and the subsequent binding of GTP to rhoB p20, a ras p21-like GTP-binding protein.J Biol Chem. 1990 Jun 5;265(16):9373-80. J Biol Chem. 1990. PMID: 2111820
-
Regulators of small GTPases.Ciba Found Symp. 1993;176:128-38; discussion 138-46. doi: 10.1002/9780470514450.ch9. Ciba Found Symp. 1993. PMID: 8299416 Review.
-
The Rho small G protein family-Rho GDI system as a temporal and spatial determinant for cytoskeletal control.Biochem Biophys Res Commun. 1998 Apr 28;245(3):641-5. doi: 10.1006/bbrc.1998.8253. Biochem Biophys Res Commun. 1998. PMID: 9588168 Review.
Cited by
-
Phosphorylation states of Cdc42 and RhoA regulate their interactions with Rho GDP dissociation inhibitor and their extraction from biological membranes.Biochem J. 2002 Jan 15;361(Pt 2):243-54. doi: 10.1042/0264-6021:3610243. Biochem J. 2002. PMID: 11772396 Free PMC article.
-
Protein kinase A phosphorylation of RhoA mediates the morphological and functional effects of cyclic AMP in cytotoxic lymphocytes.EMBO J. 1996 Feb 1;15(3):510-9. EMBO J. 1996. PMID: 8599934 Free PMC article.
-
Quantitative analysis of prenylated RhoA interaction with its chaperone, RhoGDI.J Biol Chem. 2012 Aug 3;287(32):26549-62. doi: 10.1074/jbc.M112.371294. Epub 2012 May 24. J Biol Chem. 2012. PMID: 22628549 Free PMC article.
-
The small GTP-binding protein Rho potentiates AP-1 transcription in T cells.Mol Cell Biol. 1998 Sep;18(9):4986-93. doi: 10.1128/MCB.18.9.4986. Mol Cell Biol. 1998. PMID: 9710582 Free PMC article.
-
An Arabidopsis gene isolated by a novel method for detecting genetic interaction in yeast encodes the GDP dissociation inhibitor of Ara4 GTPase.Plant Cell. 1996 Nov;8(11):2079-91. doi: 10.1105/tpc.8.11.2079. Plant Cell. 1996. PMID: 8953772 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Research Materials
Miscellaneous