Back to Search Start Over

Renal medullary gene expression in aquaporin-1 null mice

Authors :
Katherine M. Taylor-Garcia
Matthew R. McReynolds
Kevin A. Greer
Heddwen L. Brooks
James B. Hoying
Source :
American Journal of Physiology-Renal Physiology. 288:F315-F321
Publication Year :
2005
Publisher :
American Physiological Society, 2005.

Abstract

Mice that lack the aquaporin-1 gene (AQP1) lack a functional countercurrent multiplier mechanism, fail to concentrate the inner medullary (IM) interstitium, and present with a urinary concentrating defect. In this study, we use DNA microarrays to identify the gene expression profile of the IM of AQP1 null mice and corresponding changes in gene expression resulting from a loss of a hypertonic medullary interstitium. An ANOVA analysis model, CARMA, was used to isolate the knockout effect while taking into account experimental variability associated with microarray studies. In this study 5,701 genes of the possible ∼12,000 genes on the array were included in the ANOVA; 531 genes were identified as demonstrating a >1.5-fold up- or downregulation between the wild-type and knockout groups. We randomly selected 35 genes for confirmation by real-time PCR, and 29 of the 35 genes were confirmed using this method. The overall pattern of gene expression in the AQP1 null mice was one of downregulation compared with gene expression in the renal medullas of the wild-type mice. Heat shock proteins 105 and 94, aldose reductase, adenylate kinase 2, aldolase B, aldehyde reductase 6, and p8 were decreased in the AQP1 null mice. Carboxylesterase 3, matrilin 2, lipocalin 2, and transforming growth factor-α were increased in IM of AQP1 null mice. In addition, we observed a loss of vasopressin type 2 receptor mRNA expression in renal medullas of the AQP1 null mice. Thus the loss of the hyperosmotic renal interstitium, due to a loss of the concentrating mechanism, drastically altered not only the phenotype of these animals but also their renal medullary gene expression profile.

Details

ISSN :
15221466 and 1931857X
Volume :
288
Database :
OpenAIRE
Journal :
American Journal of Physiology-Renal Physiology
Accession number :
edsair.doi.dedup.....c962972ade3b4d74d41580bee20c6e31
Full Text :
https://doi.org/10.1152/ajprenal.00207.2004