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Rho inhibits cAMP-induced translocation of aquaporin-2 into the apical membrane of renal cells

Item Type:Article
Title:Rho inhibits cAMP-induced translocation of aquaporin-2 into the apical membrane of renal cells
Creators Name:Tamma, G. and Klussmann, E. and Maric, K. and Aktories, K. and Svelto, M. and Rosenthal, W. and Valenti, G.
Abstract:We have recently demonstrated that actin depolymerization is a prerequisite for cAMP-dependent translocation of the water channel aquaporin-2 (AQP2) into the apical membrane in AQP2-transfected renal CD8 cells (29). The Rho family of small GTPases, including Cdc42, Rac, and Rho, regulates the actin cytoskeleton. In AQP2-transfected CD8 cells, inhibition of Rho GTPases with Clostridium difficile toxin B or with C. limosum C3 fusion toxin, as well as incubation with the Rho kinase inhibitor, Y-27632, caused actin depolymerization and translocation of AQP2 in the absence of the cAMP-elevating agent forskolin. Both forskolin and C3 fusion toxin-induced AQP2 translocation were associated with a similar increase in the osmotic water permeability coefficient. Expression of constitutively active RhoA induced formation of stress fibers and abolished AQP2 translocation in response to forskolin. Cytochalasin D induced both depolymerization of F-actin and AQP2 translocation, suggesting that depolymerization of F-actin is sufficient to induce AQP2 translocation. Together, these data indicate that Rho inhibits cAMP-dependent translocation of AQP2 into the apical membrane of renal principal cells by controlling the organization of the actin cytoskeleton.
Keywords:Actins, Amides, Aquaporins, Bacterial Toxins, Cell Line, Cell Membrane, Cell Polarity, Cyclic AMP, Cytochalasin D, Cytoskeleton, Enzyme Inhibitors, Forskolin, Intracellular Signaling Peptides and Proteins, Collecting Kidney Tubules, Protein Transport, Protein-Serine-Threonine Kinases, Pyridines, rho GTP-Binding Proteins, rho-Associated Kinases, rhoA GTP-Binding Protein, Animals, Rabbits
Source:American Journal of Physiology Renal Physiology
Publisher:American Physiological Society
Page Range:F1092-F1101
Date:December 2001
Official Publication:https://doi.org/10.1152/ajprenal.0091.2001
PubMed:View item in PubMed

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