|
|
||||||||
Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, and Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, Mexico City, Mexico
Submitted 7 July 2008 ; accepted in final form 12 August 2008
Loss of physiological regulation of the renal thiazide-sensitive Na+-Cl– cotransporter (NCC) by mutant WNK1 or WNK4 results in pseudohypoaldosteronism type II (PHAII) characterized by arterial hypertension and hyperkalemia. WNK4 normally inhibits NCC, but this effect is lost by eliminating WNK4 catalytic activity or through PHAII-type mutations. In contrast, another member of the WNK family, WNK3, activates NCC. The positive effect of WNK3 on NCC also requires its catalytic activity. Because the opposite effects of WNK3 and WNK4 on NCC were observed in the same expression system, sequences within the WNKs should endow these kinases with their activating or inhibiting properties. To gain insight into the structure-function relationships between the WNKs and NCC, we used a chimera approach between WNK3 and WNK4 to elucidate the domain of the WNKs responsible for the effects on NCC. Chimeras were constructed by swapping the amino or carboxyl terminus domains, which flank the central kinase domain, between WNK3 and WNK4. Our results show that the effect of chimeras toward NCC follows the amino-terminal domain. Thus the amino terminus of the WNKs contains the sequences that are required for their activating or inhibiting properties on NCC.
distal convoluted tubule; diuretics; hypertension; kinase
This article has been cited by other articles:
![]() |
G. Gamba The thiazide-sensitive Na+-Cl- cotransporter: molecular biology, functional properties, and regulation by WNKs Am J Physiol Renal Physiol, October 1, 2009; 297(4): F838 - F848. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Vallon, J. Schroth, F. Lang, D. Kuhl, and S. Uchida Expression and phosphorylation of the Na+-Cl- cotransporter NCC in vivo is regulated by dietary salt, potassium, and SGK1 Am J Physiol Renal Physiol, September 1, 2009; 297(3): F704 - F712. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. B. Mount Splicing a Kinase and the Regulation of Salt Transport J. Am. Soc. Nephrol., June 1, 2009; 20(6): 1166 - 1168. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |