Project description:Previous studies of E2F family members have suggested that protein-protein interactions may be the mechanism by which E2Fs are recruited to specific genomic regions. We have addressed this hypothesis on a genome-wide scale using ChIP-seq analysis of MCF7 cell lines that express tagged wildtype and mutant E2F1 proteins. First, we performed ChIP-seq for tagged wt E2F1. Then, we analyzed E2F1 proteins that lacked the N terminal SP1 and cyclin A binding domains, the C terminal transactivation and pocket protein binding domains, and the internal marked box domain. Surprisingly, we found that the ChIP-seq patterns of the mutant proteins were identical to that of wt E2F1. However, mutation of the DNA binding domain abrogated all E2F1 binding to the genome. These results suggested that the interaction between the E2F1 DNA binding domain and a consensus motif may be the primary determinant of E2F1 recruitment. To address this possibility, we analyzed the in vivo binding sites for the in vitro-derived consensus E2F1 motif (TTTSSCGC) and also performed de novo motif analysis. We found that only 12% of the ChIP-seq peaks contained the TTTSSCGC motif. De novo motif analysis indicated that most of the in vivo sites lacked the 5M-CM-"M-BM-^@M-BM-^Y half of the in vitro derived consensus, having instead the in vivo consensus of CGCGC. In summary, our findings do not provide support for the model that protein-protein interactions are involved in recruiting E2F1 to the genome, but rather suggest that recognition of a motif found at most human promoters is the critical determinant. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf 9 total ChIP-seq datasets; four different HA-ER-E2F1 mutants, and one HA ER E2F1 wild type dataset done in duplicate, from 5 different stable cell lines derived from MCF7 cells; Three Input replicates from 2 different stable cell lines derived from MCF7 cells; HA ER E2F1 wild type duplicate dataset from MCF7 stable cells; 1 HA ER E2F1 DBDmut replicate from MCF7 stable cells cells, 1 HA ER E2F1M-CM-^NM-BM-^TC replicate from MCF7 stable cells cells, 1 HA ER E2F1M-CM-^NM-BM-^TN/C replicate from MCF7 stable cells cells, 1 HA ER E2F1M-CM-^NM-BM-^TMB replicate from MCF7 stable cells cells, 1 HA ER E2F1M-CM-^NM-BM-^TMB replicate from MCF7 stable cells cells, 3 Input replicates from MCF7 stable cells cells.
Project description:Previous studies of E2F family members have suggested that protein-protein interactions may be the mechanism by which E2Fs are recruited to specific genomic regions. We have addressed this hypothesis on a genome-wide scale using ChIP-seq analysis of MCF7 cell lines that express tagged wildtype and mutant E2F1 proteins. First, we performed ChIP-seq for tagged wt E2F1. Then, we analyzed E2F1 proteins that lacked the N terminal SP1 and cyclin A binding domains, the C terminal transactivation and pocket protein binding domains, and the internal marked box domain. Surprisingly, we found that the ChIP-seq patterns of the mutant proteins were identical to that of wt E2F1. However, mutation of the DNA binding domain abrogated all E2F1 binding to the genome. These results suggested that the interaction between the E2F1 DNA binding domain and a consensus motif may be the primary determinant of E2F1 recruitment. To address this possibility, we analyzed the in vivo binding sites for the in vitro-derived consensus E2F1 motif (TTTSSCGC) and also performed de novo motif analysis. We found that only 12% of the ChIP-seq peaks contained the TTTSSCGC motif. De novo motif analysis indicated that most of the in vivo sites lacked the 5â half of the in vitro derived consensus, having instead the in vivo consensus of CGCGC. In summary, our findings do not provide support for the model that protein-protein interactions are involved in recruiting E2F1 to the genome, but rather suggest that recognition of a motif found at most human promoters is the critical determinant. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf
Project description:E2F transcription factors are known regulators of the cell cycle, proliferation, apoptosis and differentiation. We reveal an essential role for E2F1 in liver through the regulation of glycolysis and lipogenesis. E2F1 deficiency leads to a decreased in glycolysis and de novo synthesis of fatty acids in hepatocytes. ChIP-Seq was performed to determine direct tagets of E2F1 in hepatocytes. We highlight that E2F1 directly binds the promoters of genes implicated in metabolic process and notably key lipogenic genes to control these pathways.
Project description:Our computational approach identified E2F1 as a collaborative factor for EZH2 in transcriptional regulation of cancer-related genes. This experiment is designed to validate the interaction between E2F1 and EZH2 on the chromatin. By obtaining over 1 billion bases of sequence from chromatin immunoprecipitated DNA, we generated the genome-wide localizations of E2F1 in CRPC cell line LNCaP-abl cells, and found that Indeed, these sites are enriched near the transcription start sites of EZH2-activated genes. Further analysis of the transcription factor motifs enriched at these peaks revealed the enrichement of androgen receptor motif, suggesting a co-activator role for EZH2 in concert with AR. Our work demonstrated a novel funtion of EZH2 in transcriptional activation by directly binding to the chromatin sites that cooperate with AR.
Project description:Our computational approach identified E2F1 as a collaborative factor for EZH2 in transcriptional regulation of cancer-related genes. This experiment is designed to validate the interaction between E2F1 and EZH2 on the chromatin. By obtaining over 1 billion bases of sequence from chromatin immunoprecipitated DNA, we generated the genome-wide localizations of E2F1 in CRPC cell line LNCaP-abl cells, and found that Indeed, these sites are enriched near the transcription start sites of EZH2-activated genes. Further analysis of the transcription factor motifs enriched at these peaks revealed the enrichement of androgen receptor motif, suggesting a co-activator role for EZH2 in concert with AR. Our work demonstrated a novel funtion of EZH2 in transcriptional activation by directly binding to the chromatin sites that cooperate with AR. Study of the chromatin localizations of PRC2 complex core subunits and different histone marks in 2 cell types
Project description:Differential ChIP-Seq data monitoring changes in active enhancer marks (H3K27ac sites) after treatment with siGRHL2 in MCF7 and T47D breast cancer models. Comparing sites altered by treatment with siGRHL2 after 48hours revealed these sites to be enriched for Estrogen Receptor (ER) binding.
Project description:These are three biological replicates. HeLa cells were crosslinked on separate days. In each case, a matched total from the same crosslinking was produced in parallel. Amplicons were made from each and hybridized onto ENCODE region tiling arrays. Two color arrays were used; ChIP was red, Total was green. Goal was determination of E2F1 binding sites in HeLa cells by using ChIP-chip methodology. See Farnham Lab website for downloadable protocol for ChIP or supplementary file (Chip_protocol.txt) below. NimbleGen performed all array processing. See NimbleGen website for information on array procedures.
Project description:Estrogen Receptor (ER) is a hormonal transcription factor that plays important roles in breast cancer. It functions primarily through binding to the regulatory regions of target genes containing the consensus ERE motifs. In order to identify ER target genes and re-define the ERE motifs we performed ChIP-Seq analysis of ER in MCF7 breast cancer cell line. Applying a novel computational algorithm named Hybrid Motif Sampler (HMS), specifically designed for TFBS motif discovery in ChIP-Seq data, we were able to detect an improved ERE motif and reveal intra-motif dependency especially in neighboring base pairs. MCF7 cells were grown in starving medium (RPMI with 5% FCS) for 3 days prior to the treatment with 10 nM β-estradiol or vehicle control for 45 minutes. ChIP was done using an anti-ER antibody in both the ethl-treated and the E2-treated cells. ChIP-Seq sample prep and sequencing were done following the manufacture's protocol using the Genome Analyzer (Illumina). The read files were analyzed using ethl-treated as control for E2-treated, leading to one final peak file.
Project description:This data was generated by ENCODE. If you have questions about the data, contact the submitting laboratory directly (Philip Cayting mailto:pcayting@stanford.edu). If you have questions about the Genome Browser track associated with this data, contact ENCODE (mailto:genome@soe.ucsc.edu). This track shows probable binding sites of the specified transcription factors (TFs) in the given cell types as determined by chromatin immunoprecipitation followed by high throughput sequencing (ChIP-seq). Each experiment is associated with an input signal, which represents the control condition where immunoprecipitation with non-specific immunoglobulin was performed in the same cell type. For each experiment (cell type vs. antibody) this track shows a graph of enrichment for TF binding (Signal), along with sites that have the greatest evidence of transcription factor binding, as identified by the PeakSeq algorithm (Peaks). The sequence reads, quality scores, and alignment coordinates from these experiments are available for download. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf