Functional analysis of the chicken PPARΓ gene 5′-flanking region and C/EBPα-mediated gene regulation

College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, PR China.
Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology (Impact Factor: 1.55). 04/2011; 158(4):297-303. DOI: 10.1016/j.cbpb.2011.01.001
Source: PubMed


Peroxisome proliferator-activated receptor-γ (PPARγ) and CCAAT/enhancer binding protein-α (C/EBPα) are the master regulators of adipogenesis. The regulatory mechanism of PPARγ and C/EBPα gene expression is clear in mammals, however, little is known in chicken. The aim of the present study was to characterize chicken PPARγ promoter and investigate whether PPARγ could be regulated by C/EBPα in chickens. A 2-kb nucleotide sequence upstream of the start codon of chicken PPARγ gene was cloned and characterized by using bioinformatics and experimental approaches. This 2-kb promoter region exhibited strong promoter activity in DF1 cells. The reporter gene assay showed that the chicken C/EBPα could activate PPARγ gene promoter. Further study by electrophoretic mobility shift assay and mutational analysis revealed that the chicken C/EBPα could directly bind to and regulate the PPARγ gene promoter. Our results demonstrate that PPARγ can be directly regulated by C/EBPα in chickens.

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    • "Promoter analysis of the cPPARγ gene revealed that transcription factor binding sites (such as C/EBPα, Sp1 and AP1) exist as is the case with mammalian PPARγ1 and PPARγ2 promoters. Interestingly, structure of cPPARγ promoter is more similar to the mammalian PPARγ2 promoters compared to PPARγ1 promoters [9]. These results suggest that C/EBPα-PPARγ pathway is conserved across the species and that PPARγ2 gene first appeared in the course of evolution when additional PPARγ isoforms have been acquired. "
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