60.000 cells were washed once with 100µl PBS and resuspended in 50µl lysis buffer (10mM Tris-HCl pH 7.4, 10mM NaCl, 3mM MgCl2, 0.2% IGEPAL CA-630) The suspension of nuclei was then centrifuged for 10min at 500g at 4°C, followed by the addition of 50µl transposition reaction mix (25µl TD buffer, 2.5µl Tn5 Transposase and 22.5µl Nuclease Free H2O) and incubation at 37°C for 30min. DNA was isolated using MinElute Kit (Qiagen). Libraries were amplified by PCR (13 cycles). After the PCR reaction, the library was selected for fragments between 100 and 1000bp with AmpureXP beads (Beckman Coulter). Libraries were purified with Qiaquick PCR (Qiagen) and integrity checked on a Bioanalyzer before sequencing.