AJP - Cell Physiology, Vol 255, Issue 2 C155-C161, Copyright © 1988 by American Physiological Society

ARTICLES

Modulation of Na+-Pi cotransport in opossum kidney cells by extracellular phosphate

J. Biber, J. Forgo and H. Murer
Institute of Physiology, University of Zurich, Switzerland.

The effect of the extracellular concentration of Pi on the Na+-dependent phosphate transport activity of OK cells was investigated. When incubated with extracellular Pi at concentrations of 200 microM or less, Na+-Pi cotransport increased approximately twofold in OK cells compared with control cells (kept in 0.85 mM Pi), whereas other Na+-dependent transport activities were not affected. After Pi deprivation, Na+-Pi cotransport could be inhibited to a similar extent (80%) by parathyroid hormone (PTH) as in control cells, suggesting that the PTH-sensitive Na+-Pi cotransport activity is also regulated by extracellular Pi. The increase of Na+-Pi cotransport was maximally expressed after 6 h and could be prevented by cycloheximide (70 microM) but not by actinomycin D (0.5-5 g/ml). However, the adaptive response was completely blocked by 3'-deoxyadenosine (cordycepin) at 100 microM. From these data, it is concluded that the upregulation of Na+-Pi cotransport in OK cells due to low extracellular Pi is controlled at a posttranscriptional level.

This article has been cited by other articles:

				R. Cunningham, X. E, D. Steplock, S. Shenolikar, and E. J. Weinman Defective PTH regulation of sodium-dependent phosphate transport in NHERF-1-/- renal proximal tubule cells and wild-type cells adapted to low-phosphate media Am J Physiol Renal Physiol, October 1, 2005; 289(4): F933 - F938. [Abstract] [Full Text] [PDF]

				E. J. Weinman, A. Boddeti, R. Cunningham, M. Akom, F. Wang, Y. Wang, J. Liu, D. Steplock, S. Shenolikar, and J. B. Wade NHERF-1 is required for renal adaptation to a low-phosphate diet Am J Physiol Renal Physiol, December 1, 2003; 285(6): F1225 - F1232. [Abstract] [Full Text]

				Y. Moz, J. Silver, and T. Naveh-Many Characterization of cis-acting element in renal NaPi-2 cotransporter mRNA that determines mRNA stability Am J Physiol Renal Physiol, April 1, 2003; 284(4): F663 - F670. [Abstract] [Full Text] [PDF]

				H. Murer, N. Hernando, I. Forster, and J. Biber Proximal Tubular Phosphate Reabsorption: Molecular Mechanisms Physiol Rev, October 1, 2000; 80(4): 1373 - 1409. [Abstract] [Full Text] [PDF]

				Y. Moz, J. Silver, and T. Naveh-Many Protein-RNA Interactions Determine the Stability of the Renal NaPi-2 Cotransporter mRNA and Its Translation in Hypophosphatemic Rats J. Biol. Chem., September 3, 1999; 274(36): 25266 - 25272. [Abstract] [Full Text] [PDF]

				M. F. Pfister, J. Forgo, U. Ziegler, J. Biber, and H. Murer cAMP-dependent and -independent downregulation of type II Na-Pi cotransporters by PTH Am J Physiol Renal Physiol, May 1, 1999; 276(5): F720 - F725. [Abstract] [Full Text] [PDF]

				A. W. Jehle, H. Hilfiker, M. F. Pfister, J. Biber, E. Lederer, R. Krapf, and H. Murer Type II Na-Pi cotransport is regulated transcriptionally by ambient bicarbonate/carbon dioxide tension in OK cells Am J Physiol Renal Physiol, January 1, 1999; 276(1): F46 - F53. [Abstract] [Full Text] [PDF]

				E. D. Lederer, S. S. Sohi, J. M. Mathiesen, and J. B. Klein Regulation of expression of type II sodium-phosphate cotransporters by protein kinases A and C Am J Physiol Renal Physiol, August 1, 1998; 275(2): F270 - F277. [Abstract] [Full Text] [PDF]

				M. F. Pfister, I. Ruf, G. Stange, U. Ziegler, E. Lederer, J. Biber, and H. Murer Parathyroid hormone leads to the lysosomal degradation of the renal type II Na/Pi cotransporter PNAS, February 17, 1998; 95(4): 1909 - 1914. [Abstract] [Full Text] [PDF]

				H. Hilfiker, C. M. Hartmann, G. Stange, and H. Murer Characterization of the 5'-flanking region of OK cell type II Na-Pi cotransporter gene Am J Physiol Renal Physiol, January 1, 1998; 274(1): F197 - F204. [Abstract] [Full Text] [PDF]

				M. F. Pfister, E. Lederer, J. Forgo, U. Ziegler, M. Lotscher, E. S. Quabius, J. Biber, and H. Murer Parathyroid Hormone-dependent Degradation of Type II Na+/Pi Cotransporters J. Biol. Chem., August 8, 1997; 272(32): 20125 - 20130. [Abstract] [Full Text] [PDF]