|
|
||||||||
EDITORIAL FOCUS
1Department of Anatomy and Cell Death Disease Research Center, Catholic University Medical College, Seoul 137-701, South Korea; and 2Division of Nephrology, University of Maryland, Baltimore, Maryland 21201
Submitted 10 February 2004 ; accepted in final form 22 June 2004
ABSTRACT
Tonicity-responsive enhancer binding protein (TonEBP) is a transcriptional activator of the Rel family. In the renal medulla, TonEBP stimulates genes encoding proteins involved in cellular accumulation of organic osmolytes, the vasopressin-regulated urea transporters (UT-A), and heat shock protein 70. To understand the role of TonEBP in the development of urinary concentrating ability, TonEBP expression during rat kidney development was investigated. In embryonic kidneys, TonEBP immunoreactivity was detected 16 days postcoitus in the cytoplasm of the endothelial cells surrounding the medullary collecting ducts (MCD). By 20 days, TonEBP was detected in most tubular profiles in the medulla, including the loop of Henle and MCD, and interstitial cells. The intensity of TonEBP immunoreactivity was much higher in the vasa recta than the tubules. In addition, immunoreactivity was localized predominantly to the cytoplasm. On postnatal day 1, two major changes were observed. TonEBP immunoreactivity shifted to the nucleus, and the intensity of TonEBP immunoreactivity of the tubules increased dramatically. These changes were associated with an increase in TonEBP and sodium-myo-inositol cotransporter mRNA abundance. Thereafter, TonEBP expression in tubular profiles increased moderately. The adult pattern of TonEBP expression was established at postnatal day 21 coincident with full maturation of the renal medulla. Thus expression of TonEBP in developing kidneys occurred predominantly in the medulla and preceded expression of its target genes, including UT-A. These data suggest that TonEBP contributes to the development of urine-concentrating ability.
urine concentration; sodium-myo-inositol cotransporter
This article has been cited by other articles:
![]() |
U. Hasler, V. Leroy, P.-Y. Martin, and E. Feraille Aquaporin-2 abundance in the renal collecting duct: new insights from cultured cell models Am J Physiol Renal Physiol, July 1, 2009; 297(1): F10 - F18. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. S. Jeon, K.-H. Han, S.-H. Park, S. D. Lee, M. R. Sheen, J.-Y. Jung, W. Y. Kim, J. M. Sands, J. Kim, and H. M. Kwon Downregulation of renal TonEBP in hypokalemic rats Am J Physiol Renal Physiol, July 1, 2007; 293(1): F408 - F415. [Abstract] [Full Text] [PDF] |
||||
![]() |
K.-H. Han, U-Y. Lee, Y.-S. Jang, Y. M. Cho, Y. M. Jang, I.-A Hwang, J. Y. Ghee, S.-W. Lim, W.-Y. Kim, C. W. Yang, et al. Differential regulation of B/K protein expression in proximal and distal tubules of rat kidneys with ischemia-reperfusion injury Am J Physiol Renal Physiol, January 1, 2007; 292(1): F100 - F106. [Abstract] [Full Text] [PDF] |
||||
![]() |
H.-W. Lee, W.-Y. Kim, H.-K. Song, C.-W. Yang, K.-H. Han, H. M. Kwon, and J. Kim Sequential expression of NKCC2, TonEBP, aldose reductase, and urea transporter-A in developing mouse kidney Am J Physiol Renal Physiol, January 1, 2007; 292(1): F269 - F277. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Y. Yang, W. Y. Tam, S. Tam, H. Guo, X. Wu, G. Li, J. F. L. Chau, J. D. Klein, S. K. Chung, J. M. Sands, et al. Genetic restoration of aldose reductase to the collecting tubules restores maturation of the urine concentrating mechanism Am J Physiol Renal Physiol, July 1, 2006; 291(1): F186 - F195. [Abstract] [Full Text] [PDF] |
||||
![]() |
K.-H. Han, J.-M. Lim, W.-Y. Kim, H. Kim, K. M. Madsen, and J. Kim Expression of endothelial nitric oxide synthase in developing rat kidney Am J Physiol Renal Physiol, April 1, 2005; 288(4): F694 - F702. [Abstract] [Full Text] [PDF] |
||||
![]() |
Highlights from the Literature Physiology, October 1, 2004; 19(5): 233 - 239. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |