Selectivity of fatty acid ligands for PPARα which correlates both with binding to cis-element and DNA binding-independent transactivity in Caco-2 cells
| Autor: | Kazuhito Suruga, Sachiko Takase, Kazuki Mochizuki, Yoshinobu Kiso, Harukazu Fukami, Toshinao Goda |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Transcriptional Activation
Conformational change Biology Ligands Response Elements Binding Competitive General Biochemistry Genetics and Molecular Biology chemistry.chemical_compound Humans PPAR alpha Electrophoretic mobility shift assay General Pharmacology Toxicology and Pharmaceutics chemistry.chemical_classification Retinoid X Receptor alpha Fatty acid metabolism Fatty acid General Medicine Peroxisome Lipid Metabolism DNA-Binding Proteins chemistry Biochemistry Fatty Acids Unsaturated Free fatty acid receptor Caco-2 Cells DNA Polyunsaturated fatty acid |
| Zdroj: | Life Sciences. 80:140-145 |
| ISSN: | 0024-3205 |
| Popis: | It is thought that peroxisome proliferator-activated receptor alpha (PPARalpha) is a major regulator for fatty acid metabolism. Long-chain fatty acids have been shown to induce expression of the genes related to fatty acid metabolism through PPARalpha. However, it is unclear whether the intensity of PPARalpha activation is different among various fatty acids. In this study, we compared various fatty acids in the capability of PPARalpha activation by differential protease sensitivity assay (DPSA), electrophoretic mobility shift assay and GAL4-PPAR chimera reporter assay in intestinal cell line, Caco-2. DPSA revealed that polyunsaturated fatty acids of 18 to 20 carbon groups with 3-5 double bonds strongly induced a PPARalpha conformational change. The ligand-induced changes in the sensitivity to protease corresponded to the enhancement of the binding of PPARalpha-RXRalpha heterodimer to the PPAR-response element (PPRE). The GAL4-PPAR chimera reporter assay revealed that the DNA binding-independent transactivity of PPARalpha was induced by various fatty acids with a wide spectrum of intensity which correlated with the conformational change of PPARalpha. These results suggest that PPARalpha has greater selectivity to certain types of polyunsaturated fatty acids, and that the ligand-induced conformational change of PPARalpha leads to parallel increases in both DNA binding to the PPAR-response element and the DNA binding-independent transactivity. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect