The BAC DNA was extracted using ZR BAC DNA Miniprep Kit (Zymo, D4048) following manufacturer's instructions. The purified DNA was quantified using Qibit (ThermoFisher). 50 ng of BAC DNA was incubated with recombinant c-MYC/MAX (Active Motif, 81087) or CEBPA (OriGene, TP760685), tagmentation buffer (20mM Tris,10mM MgCl2, and 20% DMF), and water in a 40 μl volume at room temperature for 1 hour. Then, a master mix consisting of 0.15 μl pre-assembled Tn5 (seqWell, Tagify(TM)), 4.85 μl dilution buffer (50mM Tris, 100mM NaCl, 0.1mM EDTA, 1mM DTT, 0.1% NP-40, and 50% glycerol), and 5 μL Tagmentation buffer was added to the samples for tagmentation in 50 μl final volume (final TF concentration of 0 nM,  50 nM and 100 nM) for 30 minutes at 37°C. Tagmented DNA was purified using a Qiagen Minelute PCR clean up kit and subsequently amplified for 5 cycles by PCR. Samples were then pooled and sequenced on a Nova platform (Illumina). Transposition into naked DNA.