title: GSM7324970: ATACseq_TPA_Gastric premalignant organoids, Trp53-/-;sgPten;sgArid1a_rep2; Mus musculus; ATAC-seq
library_construction_protocol: Organoids (5X104 cells/each group) were harvested to construct ATAC-Seq libraries using a Chromatin Profile Kit (Novoprotein, Cat. N248-01A). 1ml ice-cold PBS suspended organoids, then centrifuged at 500g at 5min. The supernatant was removed and 50ul lysis buffer gently resuspended organoids. Tubes were placed on ice for 5 min and added into 950ul wash buffer, then gently blow for 5 times, which was centrifuged at 500g for 5min at 4°C. The sediment was added into 40ul fragmented mixture and transferred to PCR tubes for 30min at 37°C. Then 10ul stop buffer used to end the reaction for 5min at 55°C. The DNA extracted beads was used for purifying fragments. Transposed DNA fragments were amplified using the PCR system from this kit. PCR conditions: 72 °C for 3 min, 98 °C for 30 s, followed by 9-18 cycles of 98 °C for 15 s, 60°C for 15 s and 72 °C for 10 s, 72 °C for 2min. Amplified libraries were purified with the DNA Clean Beads.