Frozen pellets of cross-linked cells (8-10x106) were thawed in cold lysis buffer 1 (50 mM HEPES-KOH, pH 7.5, 140 mM NaCl, 1 mM EDTA, 10% glycerol, 0.5% NP-40, 0.25% Triton X-100, 1× protease inhibitors) and gently rocked at 4°C for 10 minutes in 15 mL conical tubes. Cells were pelleted at 1350 x g at 4°C and resuspended in cold lysis buffer 2 (10 mM Tris-HCl, pH 8.0, 200 mM NaCl, 1 mM EDTA, 0.5 mM EGTA, 1× protease inhibitors) and gently rocked at 4°C for 10 minutes in 15 mL conical tubes. Cells were pelleted at 1350 x g at 4°C in a table top centrifuge and resuspended in 0.5 mL cold ChIP lysis buffer (50 mM HEPES-NaOH, pH 7.5, 140 mM NaCl, 1 mM EDTA, 1% Triton X-100, 0.1% SDS, 0.1% sodium deoxycholate) and sonicated to 200-1000 bp fragments using a VirSonic sonicator. Sonicated lysates were cleared by pelleting insoluble material at 13,000 RPM at 4°C followed by incubation with 5 ug antibody overnight. Next, Protein G magnetic beads (45 uL) were added to the lysate and incubated at 4°C for 7 hrs. ChIPExo was performed on Brg1 ChIP material while still on protein G magnetic dynabeads. After incubation with the antibody, the beads were washed six times with RIPA buffer (50mM HEPES, pH7.6, 1mM EDTA, pH8.0, 0.7% Sodium deoxycholate, 1% NP-40 and 500mM Lithium chloride) and two times with Tris (10mM Tris.Cl, pH 8.0). The bead bound DNA were end polished at 30°C for 30mins in using T4 DNA polymerase, Klenow fragment of DNA polymerase and T4 polynucleotide kinase. From this point each subsequent enzymatic steps were followed by two washes with each of RIPA and 10mM Tris. P7 adapter was ligated to the DNA ends using T4 DNA ligase at 25°C for 60 mins followed by nick repair using Phi29 polymerase at 30°C for 20 mins. Samples were periodically vortexed at 900rpm in a thermomixure during enzymatic reaction. DNA was digested with lambda and RecJf exonucleases at 37°C for 30 mins each. Samples were then eluted off the beads with 100ml of Elution buffer (50mM Tris.Cl, pH 8.0, 10mM EDTA, 1% SDS) by incubating at 65°C for 30mins with periodic shaking. RNase A was added to the samples for 30min at 37°C. Proteinase K was added to degrade proteins, crosslink was reversed by overnight incubation at 65°C and using Ampure beads ChIP DNA was purified. The purified DNA was denatured at 95°C for 5 mins before synthesis of the 2nd strand by P7 primer extension in presence of Phi29 polymerase. Then, P5 adapters were ligated to the DNA ends and the DNA fragments were PCR amplified for 18 cycles using universal primers containing the index sequences. PCR products were purified using Ampure beads, size selected using 2% agarose gels in an E-Gel Electrophoresis system (Invitrogen), gel purified using minielute gel extraction columns (Qiagen) and eluted in 20microlitre of TE. Samples were quantified and analysed on Qubit and Bioanalyser before sequencing on a Illumina Hi-Seq 2500 sequencing machine.