Expression of

DNMTs in normal hematopoiesis and leukemia cell lines. Expression of DNMTs was assayed by a standard RT-PCR method in normal peripheral cells and bone marrow cells (A), resting and PHA-activated T cells (B), various colonies formed in hematopoietic progenitor assays (C), and 3 leukemia cell lines (D). With the cells other than the hematopoietic progenitor colonies, PCR amplification was performed for 26 cycles for GAPDH (a housekeeping control), 30 cycles for DNMT1 and3A, and 35 cycles for DNMT3B (A,B,D). To amplify transcripts from the picked hematopoietic colonies, PCR was performed for 35 cycles for DNMT1, 3A, andGAPDH, and 40 cycles for DNMT3B.