title: GSM5825637: bulk_GM12878_rep2; Homo sapiens; ATAC-seq
library_construction_protocol: Cells (100,000-200,000 cells before freezing) were quickly thawed at 37℃ and centrifuged at 500 g for 5 min at 4℃. Then nuclei were isolated with Omni-ATAC lysis buffer (10 mM Tris-HCl (pH 7. 4), 10 mM NaCl, 3 mM MgCl2, 0.1% IGEPAL CA630, 0.1% Tween-20, 0.01% digitonin) and incubated on ice for 3-5 min. Nuclei were isolated with Omni-ATAC protocol lysis buffer. Then nuclei were resuspended in 50 μl tagmentation mix with Tn5 from the NovoNGS DNA Library FlashPrep Kit for Illumina, Cat. No. N233. The tagmentation reaction was performed on a thermomixer at 800 rpm, 37 °C, 30 min. To stop the tagmentation reaction, 50 μl of tagmentation stop buffer (10 mM Tris-HCl, pH 8.0, 20 mM EDTA, pH 8.0) was added to tagged nuclei. Around 20,000 nuclei stained with DAPI was sorted into 200μl tubes by FACS. The nuclei were resuspended in lysis buffer and incubated at 65℃ for 30 minutes to release Tn5. Equal volume of 10% TWEEN-20 was added to ~30ng lysed product. 2X KAPA PCR Mix was added to perform library amplification PCR: 72℃ 10 minutes; 98℃ 5 minutes; [98℃ 10 seconds, 63℃ 30 seconds, 72℃ 20 seconds] x 15 cycle; 4℃ hold. Libraries were size selected(200bp-700bp) with 2% agarose gel and sequenced on Illumina NovaSeq 6000.