GSM8517405: 10-230-ATAC; Homo sapiens; ATAC-seq
200K cells were collected, washed once with cold PBS, and pelleted by centrifugation for 5min at 4°C. Cell pellets were re-suspended in 50μl of lysis buffer per 50,000 cells processed (10mM Tris-HCl pH 7.4, 10mM NaCl, 3mM MgCl2, 0.1% Igepal CA-630), and nuclei were pelleted by centrifugation for 25min with 500 g at 4°C using a swing-out rotor with low acceleration and brake settings. Nuclei were re-suspended in 25ul of cold sterile water and added to a PCR strip tube along with 25ul of Illumina tagmentation buffer and 2.5ul of Illumina tagmentation enzyme (Illumina, cat# 20034198) per reaction. The sample was tagmented for 30 mins @ 37˚C. then cleaned using a Qiagen minelute cleanup column kit (cat # 28206) The cleaned DNA was input into PCR using NEB High-Fidelity PCR 2X Master Mix (25ul), 2.5ul of universal primer @ 25uM concentration, and 2.5ul of a unique index primer @25uM concentration per sample. Both the universal and unique index primers (24 unique primers total) were ordered from IDT. The samples underwent 10-11 total cycles of PCR amplification then cleaned with Ampure XP beads (45ul, 0.9x ratio) to remove excess primer dimer from the final library