Fig 7.

Decitabine induced reversal of DNA methylation at the ZAP70 promoter leads to an increase in acetylation of associated histone H3. (A) Namalwa cell line was treated with 1 μM Decitabine or vehicle for 24 or 48 hrs; total RNA was prepared from both samples and used for RT-PCR detection of ZAP70 expression. (B) 100 μg of native chromatin obtained from Decitabine or vehicle treated Namalwa cell lines was incubated with 10 μg of anti acetylated H3 or control; ChIP assay was carried out and R1, R2, R3 and R4 ZAP70 promoter fragments were amplified. Gels shown are representative of three replicate experiments. Statistical analysis –Mann U Whitney where (*) and (**) and indicate P < 0.05 and P < 0.01 respectively. (C) Differences between the levels of acetylated histone H3 association with the ZAP70 promoter fragments R1 to R4 were calculated using the ratio between the levels of enrichment found in chromatin from vehicle treated versus the Decitabine treated cells.