title: GSM7699150: BE2C-QCR-01; Homo sapiens; ATAC-seq
library_construction_protocol: Library preparations for ATAC-seq were based on a published protocol with minor modifications. Briefly, cells (100,000 per sample) were harvested and washed with 150 ul ice-cold Dulbecco's Phosphate-Buffered Saline (DPBS) containing protease inhibitor (PI). Nuclei were collected by centrifugation at 500 g for 10 minutes at 4 °C after cell pellets were resuspended in lysis buffer (10 mM Tris-Cl pH 7.4, 10 mM NaCl, and 3 mM MgCl2 containing 0.1% NP-40 and PI). Nuclei were incubated with Tn5 transposon enzyme in transposase reaction mix buffer (Illumina) for 30 min at 37 °C. DNAs were purified from the transposition sample by using Mini-Elute PCR purification kit (28004, Qiagen) and measured by Qubit. Polymerase chain reaction (PCR) was performed to amplify with High-Fidelity 2X PCR Master Mix [72°C/5 mins + 98 °C /30 s + 12 × (98 °C /10 s + 63 °C/30 s + 72 °C/60 s) + 72 °C/5 min]. The libraries were purified using the Mini-Elute PCR purification kit (Qiagen). ATAC-seq libraries were pair-end sequenced on HiSeq4000 (Illumina) in the Hartwell Center at St Jude Children's Research Hospital, Memphis, TN, USA.