Figure 3.

AP2α knockdown impairs both genome-wide DNA methylation and the promoter methylation of adipogenic TFs during the CI stage. (a) 5-methylcytosine immunofluorescence of 3T3-L1 preadipocytes at ci48 h. The cells were transiently transfected with either scramble siRNA (ctrl) or AP2α siRNAs (si-1 and si-2) at ci0 h and fixed at ci48 h for 5-methylcytosine immunofluorescence. Scale bars: 10 μm. (b) Quantification analyses of total nuclear 5-methylcytosine densities in AP2α knockdown cells at ci48 h. Data were collected at the same voltage and were presented as mean±S.D. (n=3). Statistical significance is indicated: ***P<0.001. (c) DNA methylation status of C/EBPβ, C/EBPα, PPARγ and Egr2 promoters. 3T3-L1 preadipocytes were transiently transfected with either scramble siRNA (ctrl) or AP2α siRNAs (si-1 and si-2) at ci0 h and collected at ci48 h. Genomic DNA samples were extracted and then subjected to bisulfite sequencing. Each column stands for a CpG site. The methylation percentage of each CpG site was shown by blue in each column. And the non-methylation percentage of each CpG site was shown by yellow in each column