CAAT/enhancer binding proteins directly modulate transcription from the peroxisome proliferator-activated receptor gamma 2 promoter.
The CCAAT/enhancer binding proteins (C/EBPs) and the peroxisome proliferator-activated receptors (PPARs) together regulate adipogenesis. The current work uses co-transfection studies to examine the C/ EBP dependence of PPAR gamma 2 transcription. Both C/ EBP alpha and C/EBP delta expression vectors activated transcription from a PPAR gamma 2 promoter/luciferase expression vector by 5-6 fold in UMR106 cells. The simultaneous transfection of the C/EBP homologous protein (CHOP) (also known as growth arrest DNA damage protein 153 or gadd153) inhibited this C/EBP-dependent activation in a concentration dependent manner. The CHOP protein is known to heterodimerize with other C/EBP proteins to form transcriptionally inactive complexes. Mutation of the two C/EBP DNA recognition elements at -340 bp and -327 bp within the PPAR gamma 2 promoter reduced the inductive effects of both C/EBP alpha and C/EBP delta. These findings demonstrate that proteins within the C/EBP family directly modulate transcription from the PPAR gamma 2 promoter.
Clarke
S L
SL
Immunobiology & Cancer Program, Oklahoma Medical Research Foundation, Oklahoma City 73104, USA.
Robinson
C E
CE
Gimble
J M
JM
D000818:Animals; D022762:CCAAT-Enhancer-Binding Proteins; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D008830:Microbodies / Q000235:genetics / Q000378:metabolism*; D016297:Mutagenesis, Site-Directed; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000502:physiology*; D010006:Osteoblasts; D011401:Promoter Regions, Genetic / Q000187:drug effects; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics*; D051742:Transcription Factor CHOP; D014157:Transcription Factors / Q000235:genetics* / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; C497250:Ddit3 protein, mouse; C497251:Ddit3 protein, rat; D009687:Nuclear Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; D051742:Transcription Factor CHOP