Regulation of the DH-PH tandem of guanine nucleotide exchange factor for Rho GTPases by phosphoinositides.
Rho GTPases act as molecular switches central in cellular processes such as cytoskeleton dynamics, migration, cell proliferation, growth or survival. Their activation is tightly regulated downstream of cell surface receptors by Guanine nucleotide Exchange Factors (GEFs), that are responsible for the specificity, the accuracy, and the spatial restriction of Rho GTPases response to extracellular cues. Because there is about four time more RhoGEFs that Rho GTPases, and GEFs do not always show a strict specificity for GTPases, it is clear that their regulation depends on specific interactions with the subcellular environment. RhoGEFs bear a peculiar structure, highly conserved though evolution, consisting of a DH-PH tandem, the DH (Dbl homology) domain being responsible for the exchange activity. The function of the PH (Pleckstrin homology) domain known to bind phosphoinositides, however, remains elusive, and reports are in many cases rather confusing. This review summarizes data on the regulation of RhoGEFs activity through interaction of the PH-associated DH domain with phosphoinositides which are considered as critical players in the spatial organization of major signaling pathways.
INSERM, UMR1048, Université Paul Sabatier, Institut des Maladies Métaboliques et Cardiovasculaires, I2MC, 1 Avenue Jean Poulhès, BP 84225, 31432 Toulouse Cedex 4, France.
Julien
J
Viaud
Frédérique
F
Gaits-Iacovoni
Bernard
B
Payrastre
D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism*; D036341:Intercellular Signaling Peptides and Proteins / Q000502:physiology*; D008051:Lipid Bilayers / Q000378:metabolism; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism / Q000494:pharmacology*; D010716:Phosphatidylinositols / Q000494:pharmacology*; D017434:Protein Structure, Tertiary; D064067:Rho Guanine Nucleotide Exchange Factors; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism*
D020662:Guanine Nucleotide Exchange Factors; D036341:Intercellular Signaling Peptides and Proteins; D008051:Lipid Bilayers; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D064067:Rho Guanine Nucleotide Exchange Factors; D020741:rho GTP-Binding Proteins