GSM7730174: ganglioid culture, DIV4_rep3; Mus musculus; ATAC-seq
Crude nuclei were isolated using IGEPAL solution from 50,000 FACS sorted tdTomato cells after 4 days in vitro. Nuclei were subjected to tagmentation using the Illumina Nextera Tn5 transposase following published protocol with some modifications. Transposition was carried out at 37°C for an hour instead of the recommended 30mins for all samples processed. DNA fragments were purified using Qiagen MinElute PCR kit and subjected to PCR amplifications using the NEBNext High-Fidelity 2x PCR Master Mix (New England Biolabs) and appropriate barcoded primers as described. Amplified fragments were further purified using AMPure XP Beads (Beckman Coulter) according to manufacturer's recommendation to remove unamplified primers before sequencing. The resulting ATAC libraries were quantified using the GloMax multi-detection system (Promega) and size distribution assayed using a TapeStation D1000 ScreenTape (Agilent). The libraries were then pooled (4 nM) for sequencing and loaded onto the HiSeq 4000 (Illumina) for paired end 100 bp reads sequencing.