library_construction_protocol: ATAC-seq sample were prepared from 5x104 cells that were resuspended in 50 μl cold ATAC-Resuspension Buffer (RSB) containing 0.1% NP40, 0.1% Tween-20, and 0.01% Digitonin and incubated on ice for 3 minutes. The suspension was then diluted with 1 ml of cold ATAC-RSB containing 0.1% Tween-20 but no NP40 or digitonin. Nuclei were pelleted at 500g for 10 min at 4°C in a fixed angle centrifuge and resuspended in 50 μl of transposition mix (25 μl 2x TD buffer, 2.5 μl transposase (100nM final), 16.5 μl PBS, 0.5 μl 1% digitonin, 0.5 μl 10% Tween-20, 5 μl H2O) and incubated at 37°C for 30 minutes in a thermomixer with 1000 rpm mixing. DNA was purified using a Zymo DNA Clean Kit and eluted in 20 μl. DNA libraries for ATAC-seq were prepared amplifying the DNA for a proper number of cycles using NEBNext 2x MasterMix.