GSM6043283: GL261-GFP_21%O2_rep2_ATACseq; Mus musculus; ATAC-seq
ATACseq was performed as previously described with some modifications (Chen et al., 2016). GL261 cells were fixed with 1% formaldehyde for 10 min and then quenched with 0.125 M glycine for 5 min at room temperature. Cells were counted and 25,000 cells were washed and subsequently lysed in cold lysis buffer (10 mM Tris-HCl, pH 7.4, 10 mM NaCl, 3 mM MgCl2 and 0.1% IGEPAL CA-630) for 5 min on ice. Cells were then centrifuged at 500xg for 8 min and cell pellets resuspended in transposition reaction according to the standard ATACseq protocol using 2.5 ul of Tn5 enzyme per 25 000 of cells (Buenrostro et al., 2015). After transposition cells were centrifuged and reverse crosslinked (50 mM Tris-Cl, 1 mM EDTA, 1% SDS, 0.2 M NaCl, 200 μg/ml proteinase K) at 65°C with an overnight shaking at 1000 rpm.  Zymo DNA Clean & Concentrator-5 columns (ZymoResearch) were used to purify DNA. Sequencing libraries were prepared according to the original ATACseq protocol (Buenrostro et al., 2015). The ATACseq libraries were assessed for appropriate quality using Bioanalyzer 2100 and subjected to paired-end sequencing (2x76 bp) using NovaSeq 6000 (Illumina).