The cells were collected and washed twice in ice-cold PBS followed by crosslinking in 1% formaldehide (methanol free) for 5 minutes. Excess of formaldehyde was quenched by addition of Tris pH 8.0 to 100nM final and Glycine 125 mM final. Chromatin was cheared using Covaris E220 for 20 min with power 140; duty 5; bursts 200/sec. We then used 5ul aliquote of sherared chromatin to decrosslink in order to test completeness of shearing. Chromatin was considered passed QC if fragments 100-600bp were >90%. For immunoprecipitation we used chromatin from 20x10^6 cells, 5ug of specific antibody and Protein-A magnetic beads (Dynal). Following roatation at 4 degrees overnight, the immune complexes were wased in Mixed Micelle Buffer, buffer 500, LiCl/detergent solution and TE buffers. DNA was eluted from the beads using 100mM NaHCO3 100mM NaCl 1% SDS and purified using AmpureXP beads. 1-10 ng of ChIP'ed DNA was used for Illumina compatibl library generation using ThruPlex DNA-seq kit with 10 to 14 cycles of amplification with single or paired end barcodes