Project description:We analyzed the genome-wide binding profile of Jarid1b in mouse ESCs. We find that Jarid1b localizes mainly to transcription start sites, of which more than 50% are also bound by Polycomb proteins and are enriched for genes encoding developmental regulators. Furthermore, we generated genome-wide mapping of H3K4me3 in LKO Scramble and LKO Jarid1b mouse ESCs. Virtually all Jarid1b binding sites are positive for H3K4me3. Upon knockdown of Jarid1b, H3K4me3 is significantly increased at Jarid1b positive regions. Examination of Jarid1b and H3K4me3 in mouse ES cells
Project description:Identification of the genome-wide binding sites of Hoxa9 and C/EBPα in a murine myeloblastic cell line transformed by Hoxa9/Meis1. Over 50% of Hoxa9 binding sites are co-bound by C/EBPα, providing mechanistic insight into the requirement of C/EBPα for Hoxa9-mediated leukemogenesis. Additionally, genome-wide occupancy of H3K4 monomethylation and H3K27 trimethylation provide additional information on the functionality of Hoxa9/C/EBPα cobound loci. Examination of two transcription factor binding sites and two histone modifications in a transformed cell line.
Project description:Identification of the genome-wide binding sites of Hoxa9 and C/EBPα in a murine myeloblastic cell line transformed by Hoxa9/Meis1. Over 50% of Hoxa9 binding sites are co-bound by C/EBPα, providing mechanistic insight into the requirement of C/EBPα for Hoxa9-mediated leukemogenesis. Additionally, genome-wide occupancy of H3K4 monomethylation and H3K27 trimethylation provide additional information on the functionality of Hoxa9/C/EBPα cobound loci.
Project description:We analyzed the genome-wide binding profile of Jarid1b in mouse ESCs. We find that Jarid1b localizes mainly to transcription start sites, of which more than 50% are also bound by Polycomb proteins and are enriched for genes encoding developmental regulators. Furthermore, we generated genome-wide mapping of H3K4me3 in LKO Scramble and LKO Jarid1b mouse ESCs. Virtually all Jarid1b binding sites are positive for H3K4me3. Upon knockdown of Jarid1b, H3K4me3 is significantly increased at Jarid1b positive regions.
Project description:ChIP-Seq, which combines chromatin immunoprecipitation (ChIP) with high-throughput massively parallel sequencing, is increasingly being used for identification of proteinM-bM-^@M-^SDNA interactions in-vivo in the genome. In general, current algorithms for ChIP-seq reads employ artificial estimation of the average length of DNA fragments for peak finding, leading to uncertain prediction of DNA-protein binding sites. Here, we present SIPeS (Site Identification from Paired-end Sequencing), a novel algorithm for precise identification of binding sites from short reads generated from paired-end Solexa ChIP-Seq technology. SIPeS uses a dynamic baseline directly via M-bM-^@M-^Xpiling upM-bM-^@M-^Y the corresponding fragments defined by the paired reads to efficiently find peaks corresponding to binding sites. The performance of SIPeS is demonstrated by analyzing the ChIP-Seq data of the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS). The robustness of SIPeS was demonstrated in higher sensitivity and spatial resolution in peak finding compared to three existing peak detection algorithms. Keywords: transcription factors (protein-DNA interactions) Examination of protein-DNA interactions in buds of Arabidopsis anther cell
Project description:ChIP-Seq, which combines chromatin immunoprecipitation (ChIP) with high-throughput massively parallel sequencing, is increasingly being used for identification of protein–DNA interactions in-vivo in the genome. In general, current algorithms for ChIP-seq reads employ artificial estimation of the average length of DNA fragments for peak finding, leading to uncertain prediction of DNA-protein binding sites. Here, we present SIPeS (Site Identification from Paired-end Sequencing), a novel algorithm for precise identification of binding sites from short reads generated from paired-end Solexa ChIP-Seq technology. SIPeS uses a dynamic baseline directly via ‘piling up’ the corresponding fragments defined by the paired reads to efficiently find peaks corresponding to binding sites. The performance of SIPeS is demonstrated by analyzing the ChIP-Seq data of the Arabidopsis basic helix-loop-helix transcription factor ABORTED MICROSPORES (AMS). The robustness of SIPeS was demonstrated in higher sensitivity and spatial resolution in peak finding compared to three existing peak detection algorithms. Keywords: transcription factors (protein-DNA interactions)
Project description:The forkhead transcription factor FOXM1 is a key regulator of the cell cycle and is overexpressed in cancer. Increased levels of FOXM1 are associated with both poor prognosis and oestrogen receptor (ERalpha) status in primary breast cancer. In this study, we map FOXM1 binding genome wide in both ERalpha-positive (MCF-7) and -negative (MDA-MB-231) breast cancer cells. We identify a common set of FOXM1 binding events at cell cycle-regulating genes, but in addition, in MCF-7 cells we find a high level of concordance with ERalpha-binding regions. FOXM1 binding at these co-binding sites is dependent on ERalpha binding, as depletion of ER protein levels reduced FOXM1 binding. FOXM1 interacts directly with both ERalpha co-activator CARM1 and is required for H3 arginine methylation at the ERalpha complex. Inhibition of FOXM1 activity with the ligand thiostrepton resulted in decreased FOXM1 binding at cca. 1400 sites genome wide and reduced expression of genes correlated with poor prognosis in ERalpha-positive tumour samples. These data demonstrate a novel role for the forkhead protein FOXM1 as an ERalpha cofactor and provide insight into the role of FOXM1 in ERalpha-positive breast cancer. The FOXM1-binding sites were mapped by ChIP-Seq in MCF-7 and MDA-MB-231 cells. Cells were treated either with thiostrepton, a FOXM1 inhibitor, or with DMSO (as control). Four replicates were performed in MCF7 cells and two replicates in MDA-MB-231 cells.
Project description:We analyzed the genome-wide binding of Tet1 in control (shScr) and Tet1 knockdown (shTet1) mouse ES cells using two different Tet1 antibodies (Tet1-C and Tet1-N). Furthermore, we generated genome-wide mapping of hydroxymethyl cytosine (hmC) and methyl cytosine (mC). We find that hmC, in contrast to mC, is also found at transcription start sites (TSSs), and that there is a significant overlap between Tet1 binding and hmC positive regions. Surprisingly, our results also suggest, that Tet1 has a role in transcriptional repression. We showed that Tet1 associates with Sin3A co-repressor complex, and by performing ChIP-sequencing of Sin3A, we find co-localisation of Tet1 and Sin3a throughout the genome Examination of Tet1 and Sin3A binding as well as hmC and mC localization in mouse ES cells