Posttranscriptional control of aquaporin-2 abundance by vasopressin in renal collecting duct principal cells
Open Access
- 1 January 2006
- journal article
- research article
- Published by American Physiological Society in American Journal of Physiology-Renal Physiology
- Vol. 290 (1), F177-F187
- https://doi.org/10.1152/ajprenal.00056.2005
Abstract
Prevailing expression levels of aquaporin-2 (AQP2) mRNA play a major role in regulating AQP2 protein abundance. Here, we investigated whether AQP2 protein abundance is regulated at a posttranscriptional level as well. The expression levels of both AQP2 mRNA and protein increase in response to arginine vasopressin (AVP) in a concentration- and time-dependent manner in cultured immortalized mouse collecting duct principal cells (mpkCCDcl4cells). AVP washout from the medium of AVP-pretreated cells revealed that AQP2 mRNA expression progressively decreased over time, whereas AQP2 protein abundance first increased immediately after AVP washout and then gradually decreased over time. Inversely, increasing AVP concentration led to a time-dependent increase of AQP2 mRNA, whereas AQP2 protein abundance first decreased immediately after AVP supplementation and then gradually increased over time. These transient effects arose from altered V2-receptor activity because they could be abolished by SR-121463B, a specific V2-receptor antagonist. Although cycloheximide administration had no effect on transient alterations of AQP2 protein content, these effects were attenuated by administration of chloroquine, a lysosomal inhibitor, or lactacystin, a proteasomal inhibitor. Short-term inhibition of PKA activity significantly increased AQP2 protein abundance and blunted the transient alterations of AQP2 protein content induced by AVP washout and supplementation. In addition, phosphorylated AQP2 abundance increased immediately after AVP supplementation. These results indicate that in response to AVP AQP2 protein abundance in collecting duct principal cells is principally influenced by AQP2 mRNA content but is additionally regulated by PKA-dependent negative feedback acting on AQP2 protein degradation.Keywords
This publication has 48 references indexed in Scilit:
- COX-2 inhibition prevents downregulation of key renal water and sodium transport proteins in response to bilateral ureteral obstructionAmerican Journal of Physiology-Renal Physiology, 2005
- Dual Effects of Hypertonicity on Aquaporin-2 Expression in Cultured Renal Collecting Duct Principal CellsJournal of the American Society of Nephrology, 2005
- Vasopressin-independent regulation of collecting duct aquaporin-2 in food deprivationKidney International, 2005
- Dual Influence of Aldosterone on AQP2 Expression in Cultured Renal Collecting Duct Principal CellsJournal of Biological Chemistry, 2003
- Transcription Factor AP-2α Is Preferentially Cleaved by Caspase 6 and Degraded by Proteasome during Tumor Necrosis Factor Alpha-Induced Apoptosis in Breast Cancer CellsMolecular and Cellular Biology, 2001
- Characterization of SR 121463A, a highly potent and selective, orally active vasopressin V2 receptor antagonist.JCI Insight, 1996
- Localization of mRNAs Encoding Ca2+-inhibitable Adenylyl Cyclases along the Renal Tubule: FUNCTIONAL CONSEQUENCES FOR REGULATION OF THE cAMP CONTENTPublished by Elsevier BV ,1996
- Increased gene expression of water channel in cirrhotic rat kidneysHepatology, 1995
- Pathophysiology of obstructive nephropathyKidney International, 1980
- Ein Fall von angeborener WortblindheitEuropean Neurology, 1937