title: GSM1233939: GM12891_H3K27me3_1; Homo sapiens; ChIP-Seq
library_construction_protocol: For ChIP-Seq, nuclear lysates were sonicated using a Branson 250 Sonifier (power setting 2, 100% duty cycle for 7 x 30-s intervals). Clarified lysates corresponding to 20 million cells were treated with 1-5ug of antibody (Table S4) coupled to Protein G Dynabeads (Invitrogen #10003D, New York). The protein-DNA complexes were washed with RIPA buffer and eluted in 1% SDS TE at 65°C. An aliquot of clarified lysate was reserved as “input DNA” and handled in parallel with the immunoprecipitated samples following elution from Dynabeads. For RNA-Seq, Total RNA was extracted using Trizol (Lifetechnologies, Grand Island, NY) reagent according to the manufacturer's instructions, then purified using the Qiagen RNeasy kit (Qiagen, Valencia, CA) and treated with RNAse-free DNase (Qiagen). RNA integrity was checked on a Bioanalyzer (Agilent, Santa Clara CA) and only RNA with an RNA integrity number (RIN) of > 9.5was used for subsequent library construction. Purified total RNA was depleted of ribosomal RNA using the Ribo-Zero Magnetic Gold Kit (Human/Mouse/Rat) (Epicentre Biotechnologies, Madison, WI). ChIP DNA sequencing libraries were generated according to Illumina DNA Tru-Seq DNA Sample Preparation Kit Instructions (Illumina Part # FC-121-2001, San Diego, CA). For RNA-Seq, stranded libraries were prepared following a dUTP protocol. Briefly, ~100 ng of rRNA depleted RNA were fragmented with 10 x fragmentation buffer (Lifetechnologies, #AM8740) for 2 min at 70 °C. First-strand cDNA synthesis was primed with random hexamers. Actinomycin D was added to reduce anti-sense artifacts. For second-strand synthesis dTTP was replaced with dUTP. The cDNA was endrepaired, A-tailed and Illumina TruSeq adapters were added. After size-selection on an agarose gel the second strand was eliminated by digestion with AmpErase Uracil Nglycosylase (UNG) (Lifetechnologies, N8080096) and after PCR amplification samples were sequenced on the Illumina Hi-Seq 2000.
attributes.tag: GEO Accession
attributes.value: GSM1233939