title: GSM1428884: DP Input BR1 ChIP-Seq; Mus musculus; ChIP-Seq
library_construction_protocol: Cells were lysed on ice in Lysis buffer (50 mM Hepes pH 7.9, 1 mM EDTA pH 8.0, 0.5 mM EGTA pH 8.0, 140 mM NaCl, 10% Glycerol, 0.5% NP-40, 0.25 % Triton, protease inhibitors and 5 mM sodium butyrate)  in order to obtain nuclei, that were washed twice with washing buffer(10 mM Tris-Cl pH 8.0, 200 mM NaCl, 1 mM EDTA pH 8.0, 0.5 mM EGTA pH 8.0, 1x protease inhibitors, 5 mM sodium butyrate)  and resuspended in shearing buffer(0.1% SDS, 1mM EDTA pH 8.0, 1x protease inhibitors, 5 mM sodium butyrate) . Then, chromatin was sheared in an average size of 200 bp using Covaris. Histones-DNA complexes were isolated using the H3K27Ac antibody. Libraries were prepared following standard procedures. Briefly, DNA was end repaired  using the End Repair kit by Epicentre.  A-tailing was performed using the large Klenow fragment enzyme by NEB.We used the TruSeq indexed adapters by Illumina. After adapter ligation DNA was PCR amplified for  10 cycles using Kapa HiFi DNA polymerase from Kapa Biosystems. Libraries were purified twice using Ampure Beads (Beckman Coulter) and subsequently were sequenced in an Illumina HiSeq 2000 instrument.