Related Experiment Video

Updated: Oct 1, 2026

Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium
08:46

Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium

Published on: September 1, 2015

The polycystic kidney disease-1 promoter is a target of the beta-catenin/T-cell factor pathway

Marianna Rodova1, M Rafiq Islam, Robin L Maser

  • 1Department of Biochemistry and Molecular Biology and the Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas 66160, USA.

The Journal of Biological Chemistry
|June 6, 2002
PubMed

Insights

Polycystic kidney disease (PKD) gene expression is regulated by the beta-catenin/TCF pathway. This pathway influences PKD1 gene activity, offering new insights into cyst formation mechanisms.

Area of Science:

  • Molecular Biology
  • Genetics
  • Cell Biology

Background:

  • Polycystic kidney disease (PKD) is linked to the PKD1 gene, with mutations causing loss-of-function and altered expression in cystic cells.
  • The molecular mechanisms governing normal PKD1 gene expression and its potential role in cystogenesis remain largely unknown.

Purpose of the Study:

  • To investigate the molecular mechanisms regulating the expression of the human PKD1 gene.
  • To determine if the beta-catenin/TCF signaling pathway influences PKD1 gene transcription.

Main Methods:

  • Analysis of a 3.3-kb 5'-proximal region of the human PKD1 gene, including sequence analysis for transcription factor binding sites.
  • Reporter gene assays in HEK293T cells to assess promoter activity and beta-catenin inducibility.
  • Gel shift assays to confirm protein-DNA interactions.
  • Treatment of HT1080 and HeLa cells to evaluate endogenous PKD1 mRNA levels in response to pathway activation.

Main Results:

  • A 2.0-kb proximal promoter region containing a T-cell factor binding element (TBE1) demonstrated inducibility by beta-catenin.
  • Beta-catenin-mediated induction was dependent on TBE1 and TCF, as confirmed by dominant-negative TCF inhibition and TBE1 deletion.
  • Endogenous PKD1 mRNA levels were elevated in response to beta-catenin pathway activation in cellular models.

Conclusions:

  • These studies identify an active promoter region for the PKD1 gene.
  • The findings strongly suggest that the PKD1 gene is a direct target of the beta-catenin/TCF signaling pathway.
  • This pathway may play a significant role in the transcriptional regulation of PKD1 and potentially in PKD pathogenesis.

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