| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department Cellular and Molecular Physiology, Yale University Medical School, Mexico City, Mexico
2 Molecular Physiology Unit, Universidad Nacional Autonoma de Mexico, New Haven, CT, USA
* To whom correspondence should be addressed. E-mail: steven.hebert{at}yale.edu.
The murine apical bumetanide-sensitive Na+-K+-2Cl- cotransporter gene (mBSC1), exhibits two spliced isoform products that differ at the C-terminal domain. A long C-terminal isoform (L-mBSC1) encodes the Na+-K+-2Cl- cotransporter and a short isoform (S-mBSC1) exerts a dominant-negative effect on L-mBSC1 cotransporter activity that is abrogated by cAMP. However, the mechanism of this dominant negative effect was not clear. In this study, we used confocal microscopic analysis of an enhanced green fluorescent protein fusion construct (L-mBSC1-EGFP) expressed to characterize the surface expression of the L-BSC1 isoform in the Xenopus laevis oocytes. Functional expression was also assessed in L-mBSC1 injected oocytes by measuring the bumetanide-sensitive 86Rb+ uptake. Oocytes injected with L-mBSC1-EGFP cRNA developed a distinct plasma membrane-associated fluorescence that colocalized with the fluorescent membrane dye, FM 4-64. The fluorescence intensity in L-mBSC1-EGFP oocytes did not change after cAMP was added to the extracellular medium. In contrast, L-mBSC1-EGFP fluorescence intensity was reduced in a dose-dependent manner with co-expression of S-mBSC1. The inhibitory effect of S-mBSC1 was abrogated by cAMP. Finally, the exocytosis inhibitor colchicine blocked the effect of cAMP on the L-mBSC1-EGFP/S-mBSC1 co-injected oocytes. All changes in L-mBSC1 surface expression correlated with modification of bumetanide-sensitive 86Rb+ uptake. Our data suggest that the dominant negative effect of S-mBSC1 on L-mBSC1 transport function is due to effects on trafficking of the cotransporter.
This article has been cited by other articles:
|
|
 |
|
  G. R. Ares, P. Caceres, F. J. Alvarez-Leefmans, and P. A. Ortiz cGMP decreases surface NKCC2 levels in the thick ascending limb: role of phosphodiesterase 2 (PDE2) Am J Physiol Renal Physiol, October 1, 2008; 295(4): F877 - F887. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. I. Abdullah, P. L. Pedraza, J. C. McGiff, and N. R. Ferreri Calcium-sensing receptor signaling pathways in medullary thick ascending limb cells mediate COX-2-derived PGE2 production: functional significance Am J Physiol Renal Physiol, October 1, 2008; 295(4): F1082 - F1089. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Welker, A. Bohlick, K. Mutig, M. Salanova, T. Kahl, H. Schluter, D. Blottner, J. Ponce-Coria, G. Gamba, and S. Bachmann Renal Na+-K+-Cl- cotransporter activity and vasopressin-induced trafficking are lipid raft-dependent Am J Physiol Renal Physiol, September 1, 2008; 295(3): F789 - F802. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. A. Sonalker and E. K. Jackson Norepinephrine, via {beta}-Adrenoceptors, Regulates Bumetanide-Sensitive Cotransporter Type 1 Expression in Thick Ascending Limb Cells Hypertension, June 1, 2007; 49(6): 1351 - 1357. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. B. E. Gagnon, R. England, L. Diehl, and E. Delpire Apoptosis-associated tyrosine kinase scaffolding of protein phosphatase 1 and SPAK reveals a novel pathway for Na-K-2C1 cotransporter regulation Am J Physiol Cell Physiol, May 1, 2007; 292(5): C1809 - C1815. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Praetorius and S. Nielsen Distribution of sodium transporters and aquaporin-1 in the human choroid plexus Am J Physiol Cell Physiol, July 1, 2006; 291(1): C59 - C67. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Moreno, P. S. Cristobal, M. Rivera, N. Vazquez, N. A. Bobadilla, and G. Gamba Affinity-defining Domains in the Na-Cl Cotransporter: A DIFFERENT LOCATION FOR Cl- AND THIAZIDE BINDING J. Biol. Chem., June 23, 2006; 281(25): 17266 - 17275. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Ikari, S. Matsumoto, H. Harada, K. Takagi, H. Hayashi, Y. Suzuki, M. Degawa, and M. Miwa Phosphorylation of paracellin-1 at Ser217 by protein kinase A is essential for localization in tight junctions J. Cell Sci., May 1, 2006; 119(9): 1781 - 1789. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Paredes, C. Plata, M. Rivera, E. Moreno, N. Vazquez, R. Munoz-Clares, S. C. Hebert, and G. Gamba Activity of the renal Na+-K+-2Cl- cotransporter is reduced by mutagenesis of N-glycosylation sites: role for protein surface charge in Cl- transport Am J Physiol Renal Physiol, May 1, 2006; 290(5): F1094 - F1102. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. B. Mount Membrane trafficking and the regulation of NKCC2 Am J Physiol Renal Physiol, March 1, 2006; 290(3): F606 - F607. [Full Text] [PDF]
|
|
|
|
|
|
P. A. Ortiz cAMP increases surface expression of NKCC2 in rat thick ascending limbs: role of VAMP Am J Physiol Renal Physiol, March 1, 2006; 290(3): F608 - F616. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. B. E. Gagnon, R. England, and E. Delpire Volume sensitivity of cation-Cl- cotransporters is modulated by the interaction of two kinases: Ste20-related proline-alanine-rich kinase and WNK4 Am J Physiol Cell Physiol, January 1, 2006; 290(1): C134 - C142. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. C. Del Castillo, M. Fedor-Chaiken, J. C. Song, V. Starlinger, J. Yoo, K. S. Matlin, and J. B. Matthews Dynamic regulation of Na+-K+-2Cl- cotransporter surface expression by PKC-{epsilon} in Cl--secretory epithelia Am J Physiol Cell Physiol, November 1, 2005; 289(5): C1332 - C1343. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Gamba Molecular Physiology and Pathophysiology of Electroneutral Cation-Chloride Cotransporters Physiol Rev, April 1, 2005; 85(2): 423 - 493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Tovar-Palacio, N. A. Bobadilla, P. Cortes, C. Plata, P. de los Heros, N. Vazquez, and G. Gamba Ion and diuretic specificity of chimeric proteins between apical Na+-K+-2Cl- and Na+-Cl- cotransporters Am J Physiol Renal Physiol, September 1, 2004; 287(3): F570 - F577. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Sabath, P. Meade, J. Berkman, P. d. l. Heros, E. Moreno, N. A. Bobadilla, N. Vazquez, D. H. Ellison, and G. Gamba Pathophysiology of functional mutations of the thiazide-sensitive Na-Cl cotransporter in Gitelman disease Am J Physiol Renal Physiol, August 1, 2004; 287(2): F195 - F203. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. G.J.F. Starremans, F. F.J. Kersten, L. P.W.J. van den Heuvel, N. V.A.M. Knoers, and R. J.M. Bindels Dimeric Architecture of the Human Bumetanide-Sensitive Na-K-Cl Co-transporter J. Am. Soc. Nephrol., December 1, 2003; 14(12): 3039 - 3046. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
