title: GSM4407573: K562_GAi_H3K27ac_ChIP-Seq; Homo sapiens; ChIP-Seq
library_construction_protocol: Nuclei were digested with 100 units of MNase at 37°C for 15 min. Mono or di-nucleosomes sized chromatin was incubated with antibodies for 3 h at 4°C and recovered with protein A agarose beads. ChIP DNA (10 ng for H3K27ac, 0.5 ng for CTCF) was processed using NEBNext ChIP-seq library (New England Biolabs) with manufacturer's instructions. The ends of ChIP DNA were repaired by NEBNext Ultra II End Prep enzyme mix and ligated with NEBNext adaptors. The concentration of adaptors was 1.5 µM for H3K27ac ChIP DNA and 0.6 µM for CTCF ChIP DNA. Adaptor-ligated DNA was selected at 200 bp size using NEBNext sample purification bead and amplified using the adaptor primers (7 cycles for H3K27ac, 12 cycles for CTCF). The fragments are purified using NEBNext sample purification beads.
attributes.tag: GEO Accession
attributes.value: GSM4407573