Figure 4
HBx enhances recruitment of DNMT3a and DNMT3b on the MTA1 promoter CpG island. (a) Chang liver cells were transfected with empty vector (EV) or p3XFLAG7.1-HBx. DNA fragments that immunoprecipitated were amplified by PCR. (b) Chang liver cells were transfected with si-GFP or mixed si-DNMT3 (si-DNMT3a and si-DNMT3b). After 72 h of transfection, whole-cell lysates were prepared and protein levels were evaluated by western blotting. (c) Chang liver cells were transfected with si-GFP or mixed si-DNMT3 (si-DNMT3a and si-DNMT3b). After 24 h of transfection, cells were transfected with EV or p3XFLAG7.1-HBx for another 24 h. Results from bisulfite sequencing analysis of the MTA1 promoter CpG island were shown. Filled squares, methylated and open squares, unmethylated. (d) Schematic representation for the HBx-induced derepression of MTA1 gene by methylation of the CpG island on the promoter.
