Rho GTPase Activity Analysis in Plant Cells

2011 ◽  
pp. 135-144 ◽  
Author(s):  
Tongda Xu
Keyword(s):  
Rho Gtpase ◽  
Plant Cells ◽  
Activity Analysis ◽  
Gtpase Activity

Isolation of polypeptides with microtubule-translocating activity from phragmoplasts of tobacco BY-2 cells

1994 ◽  
Vol 107 (8) ◽  
pp. 2249-2257 ◽  
Author(s):  
T. Asada ◽  
H. Shibaoka
Keyword(s):  
Motor Activity ◽  
Molecular Basis ◽  
Plant Cells ◽  
Cell Plate ◽  
Gtpase Activity ◽  
High Concentration ◽  
Higher Plant ◽  
Main Components ◽  
Brain Tubulin

As part of our efforts to understand the molecular basis of the microtubule-associated motility that is involved in cytokinesis in higher plant cells, an attempt was made to identify proteins with the ability to translocate microtubules in an extract from isolated phragmoplasts. Homogenization of isolated phragmoplasts in a solution that contained MgATP, MgGTP and a high concentration of NaCl resulted in the release from phragmoplasts of factors with ATPase and GTPase activity that were stimulated by microtubules. A protein fraction with microtubule-dependent ATPase and GTPase activity caused minus-end-headed gliding of microtubules in the presence of ATP or GTP. Polypeptides with microtubule-translocating activity cosedimented with microtubules that had been assembled in vitro from brain tubulin and were dissociated from sedimented microtubules by addition of ATP or GTP. After cosedimentation and dissociation procedures, a 125 kDa polypeptide and a 120 kDa polypeptide were recovered in a fraction that supported minus-end-headed gliding of microtubules. The rate of microtubule gliding that was caused by the fraction that contained the 125 kDa and 120 kDa polypeptides as main components was 1.28 microns/minute in the presence of ATP and 0.50 microns/minute in the presence of GTP. This fraction contained some microtubule-associated polypeptides in addition to the 125 kDa and 120 kDa polypeptides, but a fraction that contained only these additional polypeptides did not cause any translocation of microtubules. Thus, it appeared that the 125 kDa and 120 kDa polypeptides were responsible for translocation of microtubules. These polypeptides with plus-end-directed motor activity may play an important role in formation of the cell plate and in the organization of the phragmoplast.

scholarly journals Inactivation of Rho GTPases by Statins Attenuates Anthrax Lethal Toxin Activity

2008 ◽  
Vol 77 (1) ◽  
pp. 348-359 ◽  
Author(s):  
Aimee M. deCathelineau ◽  
Gary M. Bokoch
Keyword(s):  
Rho Gtpases ◽  
Rho Gtpase ◽  
Protective Antigen ◽  
Biological Effects ◽  
Lethal Factor ◽  
Lethal Toxin ◽  
Mitogen Activated Protein Kinase ◽  
Gtpase Activity ◽  
Anthrax Lethal Toxin ◽  
Reductase Inhibitors

ABSTRACT Anthrax lethal factor (LF), secreted by Bacillus anthracis, interacts with protective antigen to form a bipartite toxin (lethal toxin [LT]) that exerts pleiotropic biological effects resulting in subversion of the innate immune response. Although the mitogen-activated protein kinase kinases (MKKs) are the major intracellular protein targets of LF, the pathology induced by LT is not well understood. The statin family of HMG-coenzyme A reductase inhibitors have potent anti-inflammatory effects independent of their cholesterol-lowering properties, which have been attributed to modulation of Rho family GTPase activity. The Rho GTPases regulate vesicular trafficking, cytoskeletal dynamics, and cell survival and proliferation. We hypothesized that disruption of Rho GTPase function by statins might alter LT action. We show here that statins delay LT-induced death and MKK cleavage in RAW macrophages and that statin-mediated effects on LT action are attributable to disruption of Rho GTPases. The Rho GTPase-inactivating toxin, toxin B, did not significantly affect LT binding or internalization, suggesting that the Rho GTPases regulate trafficking and/or localization of LT once internalized. The use of drugs capable of inhibiting Rho GTPase activity, such as statins, may provide a means to attenuate intoxication during B. anthracis infection.

scholarly journals Low-dose Chemotherapeutic Agents Regulate Small Rho GTPase Activity in Dendritic Cells

2008 ◽  
Vol 31 (5) ◽  
pp. 491-499 ◽  
Author(s):  
Galina V. Shurin ◽  
Irina L. Tourkova ◽  
Michael R. Shurin
Keyword(s):  
Dendritic Cells ◽  
Low Dose ◽  
Rho Gtpase ◽  
Chemotherapeutic Agents ◽  
Gtpase Activity

Bacterial Toxins that Modulate Rho GTPase Activity

2014 ◽  
pp. 283-292
Author(s):  
James B. Bliska ◽  
Gloria I. Viboud
Keyword(s):  
Rho Gtpase ◽  
Bacterial Toxins ◽  
Gtpase Activity

Activation of the lectin DC-SIGN induces an immature dendritic cell phenotype triggering Rho-GTPase activity required for HIV-1 replication

2007 ◽  
Vol 8 (6) ◽  
pp. 569-577 ◽  
Author(s):  
Ashleigh Hodges ◽  
Katherine Sharrocks ◽  
Mariola Edelmann ◽  
Dilair Baban ◽  
Arnaud Moris ◽  
...  
Keyword(s):  
Dendritic Cell ◽  
Rho Gtpase ◽  
Immature Dendritic Cell ◽  
Cell Phenotype ◽  
Gtpase Activity ◽  
Hiv 1

scholarly journals Corrigendum: A GAL4-inducible transgenic tool kit for the in vivo modulation of Rho GTPase activity in zebrafish

2017 ◽  
Vol 246 (6) ◽  
pp. 485-485
Author(s):  
Nicholas J. Hanovice ◽  
Emily McMains ◽  
Jeffrey M. Gross
Keyword(s):  
Rho Gtpase ◽  
Gtpase Activity

scholarly journals The Amot/Patj/Syx signaling complex spatially controls RhoA GTPase activity in migrating endothelial cells

Blood ◽  
2009 ◽  
Vol 113 (1) ◽  
pp. 244-253 ◽  
Author(s):  
Mira Ernkvist ◽  
Nathalie Luna Persson ◽  
Stéphane Audebert ◽  
Patrick Lecine ◽  
Indranil Sinha ◽  
...  
Keyword(s):  
Rho Gtpase ◽  
Critical Role ◽  
Gtpase Activity ◽  
Directional Migration ◽  
Rhoa Activity ◽  
Signaling Complex ◽  
Morpholino Knockdown ◽  
Rhoa Gtpase ◽  
Related Proteins

Abstract Controlled regulation of Rho GTPase activity is an essential component mediating growth factor–stimulated migration. We have previously shown that angiomotin (Amot), a membrane-associated scaffold protein, plays a critical role during vascular patterning and endothelial migration during embryogenesis. However, the signaling pathways by which Amot controls directional migration are not known. Here we have used peptide pull-down and yeast 2-hybrid (Y2H) screening to identify proteins that interact with the C-terminal PDZ-binding motifs of Amot and its related proteins AmotL1 and 2. We report that Amot and its related proteins bind to the RhoA GTPase exchange factor (RhoGEF) protein Syx. We show that Amot forms a ternary complex together with Patj (or its paralogue Mupp1) and Syx. Using FRET analysis, we provide evidence that Amot controls targeting of RhoA activity to lamellipodia in vitro. We also report that, similar to Amot, morpholino knockdown of Syx in zebrafish results in inhibition of migration of intersegmental arteries. Taken together, our results indicate that the directional migration of capillaries in the embryo is governed by the Amot:Patj/Mupp1:Syx signaling that controls local GTPase activity.

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