title: ATAC-seq of mus musculus gut ILC2_2
design: ATAC-seq was performed according to published protocol (Buenrostro et al., 2013) with minor modification. 10,000 cells were pelleted and washed with 500ul 1xPBS. Transposition was performed directly on nuclei using 25 l tagmentation reaction mix (Tagment DNA Buffer #15027866, Tagment DNA Enzyme #15027865 from Illumina Digitonin #G9441 from Promega). After pelleting the nuclei by centrifuging at 500x g for 10 min, the pellets were re-suspended in 45 l transposition reaction mix to tag and fragmentalize accessible chromatin. The reaction was incubated at 37C with shaking at 300rpm for 30 min. The fragmentalized DNAs were then purified using Qiagen MinElute Kit (#28006 Quiagen) and amplified using NEBNext High-Fidelity 2x PCR Master Mix (New England Biolabs #M0541) with Nextera DNA CD Indexes, according to the following program: .72 C for 5 minutes; 98 C for 30 seconds; 18 cycles of 98 C for 10 seconds, 63 C for 30 seconds, and 72 C for 1 minute. Once the libraries are purified using PCR Purification Kit (#28106 Quiagen), they were further sequenced for 50 cycles (paired-end reads) on HiSeq2500.