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Series GSE29611 Query DataSets for GSE29611
Status Public on Jun 02, 2011
Title Histone Modifications by ChIP-seq from ENCODE/Broad Institute
Project ENCODE
Organism Homo sapiens
Experiment type Genome binding/occupancy profiling by high throughput sequencing
Summary This data was generated by ENCODE. If you have questions about the data, contact the submitting laboratory directly ( If you have questions about the Genome Browser track associated with this data, contact ENCODE (

This track displays maps of chromatin state generated by the Broad/MGH ENCODE group using ChIP-seq. Chemical modifications (methylation, acetylation) to the histone proteins present in chromatin influence gene expression by changing how accessible the chromatin is to transcription.
The ChIP-seq method involves first using formaldehyde to cross-link histones and other DNA-associated proteins to genomic DNA within cells. The cross-linked chromatin is subsequently extracted, mechanically sheared, and immunoprecipitated using specific antibodies. After reversal of cross-links, the immunoprecipitated DNA is sequenced and mapped to the human reference genome. The relative enrichment of each antibody-target (epitope) across the genome is inferred from the density of mapped fragments.
For data usage terms and conditions, please refer to and
Overall design ChIP-seq: Cells were grown according to the approved ENCODE cell culture protocols. Cells were fixed in 1% formaldehyde and resuspended in lysis buffer. Chromatin was sheared to 200-700 bp using a Diagenode Bioruptor. Solubilized chromatin was immunoprecipitated with antibodies against each of the histone antibodies listed above. Antibody-chromatin complexes were pulled-down using protein A-sepharose (or anti-IgM-conjugated agarose for RNA polymerase II), washed and then eluted. After cross-link reversal and proteinase K treatment, immunoprecipitated DNA was extracted with phenol-chloroform, ethanol precipitated, treated with RNAse and purified. One to ten nanograms of DNA were end-repaired, adapter-ligated and sequenced by Illumina Genome Analyzers as recommended by the manufacturer.
Alignment: Sequence reads from each IP experiment were aligned to the human reference genome (GRCh37/hg19) using MAQ with default parameters, except '-C 11' and '-H output_file', which outputs up to 11 additional best matches for each read (if any are found) to a file. This information was used to filter out any read that had more than 10 best matches on the genome. Note: It is likely that instances where multiple reads align to the same position and with the same orientation are due to enhanced PCR amplification of a single DNA fragment. No attempt has been made, however, to remove such artifacts from the data, following ENCODE practices.
Signal: Fragment densities were computed by counting the number of reads overlapping each 25 bp bin along the genome. Densities were computed using igvtools count with default parameters (in particular, '-w 25' to set window size of 25 bp and '-f mean' to report the mean value across the window), except for '-e' set to extend the reads to 200 bp, and the .wig output was converted to bigWig using wigToBigWig from the UCSC Kent software package.
Peaks: Discrete intervals of ChIP-seq fragment enrichment were identified using Scripture, a scan statistics approach, under the assumption of uniform background signal. All data sets where processed with '-task chip', and with '-windows 100,200,500,1000,5000,10000,100000'. (No mask file nor the '-trim' option have been used.) The resulting called segments were then further filtered to remove intervals that are significantly enriched only because they contain smaller enriched intervals within them. This post-processing step has been implemented using Matlab. The use of the post-processing step allowed very large enriched intervals (of the order of Mbps for H3K27me3, for instance) to be detected, as well as much smaller intervals, without the need to tailor the parameters of Scripture based on prior expectations.
Web link
Contributor(s) Shoresh N
Citation(s) 22955616
BioProject PRJNA63443
Submission date May 27, 2011
Last update date Mar 07, 2023
Contact name ENCODE DCC
Organization name ENCODE DCC
Street address 300 Pasteur Dr
City Stanford
State/province CA
ZIP/Postal code 94305-5120
Country USA
Platforms (3)
GPL9115 Illumina Genome Analyzer II (Homo sapiens)
GPL10999 Illumina Genome Analyzer IIx (Homo sapiens)
GPL11154 Illumina HiSeq 2000 (Homo sapiens)
Samples (296)
GSM733636 Bernstein_NHEK_CTCF
GSM733637 Bernstein_HSMM_H3K4me3
GSM733638 Bernstein_HepG2_H3K9ac
SRA SRP006944

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE29611_RAW.tar 331.7 Gb (http)(custom) TAR (of BAM, BIGWIG, BROADPEAK)
GSE29611_run_info.txt.gz 9.7 Kb (ftp)(http) TXT
SRA Run SelectorHelp
Raw data are available in SRA
Processed data provided as supplementary file

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