GSM7729053: Human male naive hESC WIN1 - H3K27AC; Homo sapiens; ChIP-Seq
Histone Modifications were assesed by means of X-linked ChIP Histone modification genome-wide position data generated in this study were acquired using ChIP after crosslinking cells.  Briefly, cells were grown to a final concentration of 5x107 cells for each ChIP-seq experiment. Cells were chemically cross-linked at room temperature by the addition of formaldehyde to 1% final concentration for 10 minutes and quenched with 0.125 M final concentration glycine. Cross-linked cells were re-suspended in sonication buffer (50mM Hepes-KOH pH 7.5, 140mM NaCl, 1mM EDTA, 1% TritonX-100, 0.1% Na-deoxycholate, 0.1% SDS) and sonicated using a Diagenode Bioruptor for three 10-minute rounds using pulsing settings (30 sec ON; 1 min OFF). 10 ug of sonicated chromatin was then incubated overnight at 4oC with 5 ug of antibodies-conjugated to magnetic beads.  Following the IP the beads were washed twice with RIPA buffer (50mM Tris-HCl pH8, 150 mM NaCl, 2mM EDTA, 1% NP-40, 0.1% Na-deocycholate, 0.1% SDS), low salt buffer (20mM Tris pH 8.1, 150mM NaCl, 2mM EDTA, 1% Triton X-100, 0.1% SDS), high salt buffer (20mM Tris pH 8.1, 500mM NaCl, 2mM EDTA, 1% Triton X-100, 0.1% SDS), LiCl buffer (10mM Tris pH 8.1, 250mM LiCl, 1mM EDTA, 1% Na-deoxycholate, 1% NP-40), and 1xTE. Finally, DNA was extracted by reverse crosslinking at 60oC overnight with proteinase K (20ug/ul) and 1% SDS followed by phenol:chloroform:iso-amylacohol purification. Libraries were constructed as indicated below and sequenced using paired-end 50 bp sequencing reactions TruSeq illumina barcodes were ligated to immunoprecipitated DNA following end-repair. Minimal PCR amplification of 7-9 cycles produced suffienct material for sequening on a NovaSeq S2.