Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2004 Jul 16;5(1):46.
doi: 10.1186/1471-2164-5-46.

Expression profile of genes regulated by activity of the Na-H exchanger NHE1

Luanna K Putney  1 , Diane L Barber
Affiliations

Expression profile of genes regulated by activity of the Na-H exchanger NHE1

Luanna K Putney et al. BMC Genomics. .

Abstract

Background: In mammalian cells changes in intracellular pH (pHi), which are predominantly controlled by activity of plasma membrane ion exchangers, regulate a diverse range of normal and pathological cellular processes. How changes in pHi affect distinct cellular processes has primarily been determined by evaluating protein activities and we know little about how pHi regulates gene expression.

Results: A global profile of genes regulated in mammalian fibroblasts by decreased pHi induced by impaired activity of the plasma membrane Na-H exchanger NHE1 was characterized by using cDNA microarrays. Analysis of selected genes by quantitative RT-PCR, TaqMan, and immunoblot analyses confirmed results obtained from cDNA arrays. Consistent with established roles of pHi and NHE1 activity in cell proliferation and oncogenic transformation, grouping regulated genes into functional categories and biological pathways indicated a predominant number of genes with altered expression were associated with growth factor signaling, oncogenesis, and cell cycle progression.

Conclusion: A comprehensive analysis of genes selectively regulated by pHi provides insight on candidate targets that might mediate established effects of pHi on a number of normal and pathological cell functions.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Relative functional clustering of genes differentially regulated in LAPE cells. Percentage of genes in the indicated functional categories that were regulated (A), had increased expression (B), and decreased expression in LAPE cells compared with LAPN cells (p < 0.05, n = 5).
Figure 2
Figure 2
Genes differentially regulated in LAPE cells grouped as functioning in growth factor signaling and transcriptional regulation. A. Schematic diagram of growth factor signaling and transcriptional regulation. Red indicates genes with increased expression in LAPE cells compared with LAPN cells, and blue indicates genes with decreased expression. B. Immunoblot analysis of the indicated proteins confirmed increased protein expression in LAPE cells predicted by GeneChip data. C. Relative RT-PCR for the transcription factor C/EBP delta confirmed GeneChip data of increased expression in LAPE cells compared with LAPN cells. D. TaqMan analysis confirmed increased expression of GADD153 in LAPE cells compared with LAPN cells. Data in A represent the means of fold-increase or – decrease in LAPE cells (p < 0.05, n = 5). Data in B, C, and D are representative of 2 to 3 separate cell preparations.
Figure 3
Figure 3
Genes differentially regulated in LAPE cells grouped as functioning in the G2/M transition of cell cycle progression and DNA damage checkpoint. A. Schematic diagram of G2/M regulation. Red indicates genes with increased expression in LAPE cells compared with LAPN cells, and blue indicates genes with decreased expression. B. Immunoblot of GADD45 confirmed decreased protein expression in LAPE cells compared with LAPN cells. C. Immunblotting for FEN1 and cyclin B1 at the indicated times after release from a double thymidine block. C. Relative TaqMan expression of Wee1 kinase confirmed GeneChip data of increased Wee1 expression in LAPE cells compared with LAPN cells. Data in A represent the means of fold-increase or – decrease in LAPE cells (p < 0.05, n = 5). Data in B and C are representative of 2 to 3 separate cell preparations. Data in D represent the mean ± s.e.m. of 3 separate cell preparations.
Figure 5
Figure 5
Expression of cytoskeleton and extracellular matrix genes differentially regulated in LAPE cells. A. Immunoblotting for gelsolin (top panel) and zymography for type IV collagenase (MMP-9) activity (bottom panel) confirmed increases and decreases, respectively, in LAPE cells compared with LAPN cells observed with GeneChip data. B. Relative TaqMan analysis indicated decreased p24p3 expression in LAPE cells, consistent with GeneChip data.
Figure 4
Figure 4
Genes differentially regulated in LAPE cells grouped as functioning in glycolysis, electron transport and oxidative phosphorylation. A. Schematic diagram of carbohydrate metabolism and oxidative phosphorylation. Red indicates genes with increased expression in LAPE cells compared with LAPN cells, and blue indicates genes with decreased expression. B. Relative TaqMan expression of Glut-4 confirmed GeneChip data of decreased Glut-4 expression in LAPE cells compared with LAPN cells. Data in A represent the means of fold-increase or – decrease in LAPE cells (p < 0.05, n = 5). Data in B are representative of 2 separate cell preparations.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Serrano R, Ruiz A, Bernal D, Chambers JR, Arino J. The transcriptional response to alkaline pH in Saccharomyces cerevisiae: evidence for calcium-mediated signalling. Mol Microbiol. 2002;46:1319–1333. doi: 10.1046/j.1365-2958.2002.03246.x. - DOI - PubMed
    1. Olson ER. Influence of pH on bacterial gene expression. Mol Microbiol. 1993;8:5–14. - PubMed
    1. Putney LK, Denker SP, Barber DL. The changing face of the Na+/H+ Exchanger, NHE1: Structure, regulation, and cellular actions. In: Schekman R, Goldstein LB, McKnight SL, Rossant J, editor. Annu Rev Pharmacol Toxicol. Vol. 42. Palo Alto; 2002. pp. 527–552. - DOI - PubMed
    1. Orlowski J, Grinstein S. Diversity of the mammalian sodium/proton exchanger SLC9 gene family. Pflugers Arch. 2004;447:549–565. doi: 10.1007/s00424-003-1110-3. - DOI - PubMed
    1. Putney LK, Barber DL. Na-H Exchange-dependent increase in intracellular pH times G2/M entry and transition. J Biol Chem. 2003;278:44645–44649. doi: 10.1074/jbc.M308099200. - DOI - PubMed

Publication types

MeSH terms

LinkOut - more resources