Related Experiment Video
Updated: Aug 17, 2026

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation
Published on: June 27, 2017
Modulation of selenoprotein P expression by TGF-beta(1) is mediated by Smad proteins
V Mostert1, I Dreher, J Köhrle
1Abteilung Experimentelle Toxikologie, Medizinisches Institut für Umwelthygiene, Heinrich-Heine-Universität, Auf'm Hennekamp 50, 40225 Düsseldorf, Germany.
Abstract:
Selenoprotein P (SeP) is a selenium-rich plasma protein which accounts for more than 50% this study, the effect of TGF-beta(1) on the expression of SeP in the human liver cell line HepG2 was investigated. Western analysis revealed a dose-dependent reduction of SeP content in cell supernatant. RT-PCR analysis of SeP-mRNA expression demonstrated a marked inhibition and a reporter gene under control of the SeP promoter was negatively regulated by TGF-beta(1). Smad proteins are the transcriptional mediators of TGF-beta signaling. A putative Smad-binding element (SBE) is present in the SeP promoter. In electrophoretic-mobility-shift assays, TGF-beta(1) enhanced the binding of nuclear proteins to this SBE. Overexpression of Smad3 and 4 resulted in a downregulation of SeP-promoter activity whereas deletion of the SBE led to a loss of TGF-beta(1) responsiveness. We conclude that SeP expression is modulated by the binding of Smad3/4 complexes to a functional SBE in the SeP promoter.
More Related Videos
06:54Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
Published on: October 27, 2020
11:38Visualization and Quantification of TGFβ/BMP/SMAD Signaling under Different Fluid Shear Stress Conditions using Proximity-Ligation-Assay
Published on: September 14, 2021
Related Concept Videos
Cell Specific Gene Expression
Regulation of Nuclear Protein Sorting
Hedgehog Signaling Pathway
The JAK-STAT Signaling Pathway
TGF - β Signaling Pathway
Regulation of Expression at Multiple Steps