Related Experiment Video

Updated: Jun 19, 2026

Live-cell Measurement of Odorant Receptor Activation Using a Real-time cAMP Assay
09:11

Live-cell Measurement of Odorant Receptor Activation Using a Real-time cAMP Assay

Published on: October 2, 2017

Mouse OCTN2 is directly regulated by peroxisome proliferator-activated receptor alpha (PPARalpha) via a PPRE located

Gaiping Wen1, Robert Ringseis, Klaus Eder

  • 1Institute of Agricultural and Nutritional Sciences, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 2, 06120 Halle (Saale), Germany.

Biochemical Pharmacology
|October 13, 2009
PubMed

Insights

Organic cation transporter 2 (OCTN2) is upregulated by peroxisome proliferator-activated receptor alpha (PPARalpha). This study identifies a functional peroxisome proliferator response element (PPRE) in the first intron of the OCTN2 gene, confirming PPARalpha as a direct regulator.

Area of Science:

  • Molecular Biology
  • Gene Regulation
  • Pharmacology

Background:

  • Organic cation transporter 2 (OCTN2) is suggested to be a direct target of peroxisome proliferator-activated receptor alpha (PPARalpha).
  • Previous research has not identified a functional peroxisome proliferator response element (PPRE) in the OCTN2 promoter region.

Purpose of the Study:

  • To investigate the hypothesis that OCTN2 is transcriptionally induced by PPARalpha via a functional PPRE located in the first intron.
  • To elucidate the precise mechanism of PPARalpha-mediated OCTN2 gene regulation.

Main Methods:

  • In silico analysis of the mouse OCTN2 first intron for putative PPREs.
  • Reporter gene assays using constructs with OCTN2 intron PPREs and PPARalpha/RXRalpha activation.
  • Site-directed mutagenesis of identified PPREs to assess functional significance.
  • Gel shift assays to confirm PPARalpha/RXRalpha heterodimer binding to PPREs.

Main Results:

  • Eleven putative PPREs were identified in the mouse OCTN2 first intron.
  • Reporter assays demonstrated a marked response to PPARalpha/RXRalpha activation via a PPRE cluster (PPREint-1-8-10).
  • Mutational analysis revealed PPRE1 as critical for PPARalpha-mediated transcriptional activation, with PPRE8 and PPRE10 also contributing.
  • Gel shift assays confirmed direct binding of PPARalpha/RXRalpha to PPRE1.

Conclusions:

  • Mouse OCTN2 is a direct target gene of PPARalpha.
  • Transcriptional upregulation of OCTN2 by PPARalpha is mediated through PPRE1 located in the gene's first intron.
  • This finding clarifies the regulatory mechanism of OCTN2 expression by PPARalpha.

More Related Videos

Protein Transfection of Mouse Lung04:21

Protein Transfection of Mouse Lung

Published on: May 15, 2013

Related Concept Videos

Transducer Mechanism: Nuclear Receptors01:31

Transducer Mechanism: Nuclear Receptors

Nuclear receptors, or NRs, are unique transcription factors that regulate gene transcription and affect the cellular pathways involved in reproduction, development, or metabolism. Their ability to be stimulated by small lipophilic ligands and control vital cellular processes makes them ideal drug targets. Nearly 10-15% of currently prescribed drugs target these receptors.
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
Regulation of Nuclear Protein Sorting01:45

Regulation of Nuclear Protein Sorting

Nuclear protein sorting regulates nucleus composition and gene expression, crucial for determining the fate of a eukaryotic cell. Hence, the entry and exit of molecules across the nuclear envelope is a tightly controlled process. Nuclear protein sorting can be inhibited by one of the following ways: 1) masking cargo signal sequences, 2) modifying the nuclear receptor's affinity for cargo, 3) controlling the nuclear pore size, 4) retaining the cargo during its transit to the cytosol or the...
Protein Import into the Peroxisomes01:27

Protein Import into the Peroxisomes

Cells contain membrane-bound organelles called peroxisomes that oxidize organic molecules by transferring hydrogen atoms to oxygen, producing hydrogen peroxide. Peroxisomes enzymatically convert the released hydrogen peroxide into water and oxygen.
Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...
Master Transcription Regulators02:23

Master Transcription Regulators

Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a  complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
Cell Specific Gene Expression01:58

Cell Specific Gene Expression

Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
Peroxisomes01:24

Peroxisomes

Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...