title: GSM8126199: ATAC-seq Normoxia 2; Homo sapiens; ATAC-seq
library_construction_protocol: Cells were detached from the plates using trypsin, and 5 × 104 detached cells were collected into a 1.5 ml tube. Cells were centrifuged at 500 g, 4°C for 5 minutes and washed twice with 1× iced cold PBS.  Cell pellets were resuspended in 50 µl ATAC resuspend buffer (ATAC-RSB) (10 mM Trizma pH 7.8, 10 mM NaCl and 3 mM MgCl2), supplemented with 0.1% NP-40, 0.1% Tween-20, and 0.01% digitonin. The mixture was gently pipetted and incubated on ice for 3 minutes. To quench the lysis, 1 ml ATAC-RSB supplemented with 0.1% Tween-20 was added. The samples were centrifuged at 500 g, 4°C for 5 minutes to pellet the nuclei. The nuclei were subjected to a transposase mix (2.5 µl TDE1, 25 µl 2X TD buffer, 16.5 µl 1× PBS, 0.5 µl 10% Tween-20, 0.5 µl 1% digitonin and 5 µl ultra pure water) and reaction was performed at 37°C with shaking at 1,000 r.p.m. on a ThermoMixer for 30 minutes. After transposition, DNA was purified using the DNA Clean & Concentrator-5 kit (Zymo), following the manufacturer's protocol. PCR was performed using the NEBNext High-Fidelity 1× PCR Master Mix, supplemented with primers containing the sequence of Illumina adapters and indexes, to generate sequencing libraries.