Project description:In skeletal myogenesis, the transcription factor MyoD activates distinct transcriptional programs in progenitors compared to terminally differentiated cells. Using ChIP-seq and gene expression analyses, we show that in primary myoblasts, Snail-HDAC1/2 repressive complex bind and exclude MyoD from its targets. Notably, Snail binds E-box motifs that are G/C-rich in their central dinucleotides, and such sites are almost exclusively associated with genes expressed during differentiation. By contrast, Snail does not bind the A/T-rich E-boxes associated with MyoD targets in myoblasts. Thus, Snai1-HDAC1/2 prevents MyoD occupancy on differentiation-specific regulatory elements and the change from Snail- to MyoD-binding often results in enhancer switching during differentiation. Furthermore, we show that a regulatory network involving Myogenic Regulatory Factors (MRFs), Snail/2, miR-30a and miR-206 acts as a molecular switch that controls entry into myogenic differentiation. Together, these results reveal a regulatory paradigm that directs distinct gene expression programs in progenitors versus terminally differentiated cells. Genome wide binding sites of various transcription factors and chromatin modifiers in muscle cells
Project description:Examination of binding locations of Pax3 and Pax7 in primary myoblasts UCSC track hub available at: http://www.ogic.ca/projects/Soleimani_2012_Pax7_hub/hub.txt For details on viewing the track hub in the UCSC Genome Browser: http://altair.dartmouth.edu/ucsc/goldenPath/help/hgTrackHubHelp.html#View 3 Samples (Control, Pax7 ChIP, Pax3 ChIP)
Project description:This SuperSeries is composed of the following subset Series: GSE24811: Time Series of Mouse skeletal muscle cell differentiation GSE24852: ChIP-Seq of MyoD, Myf5, Snai1, HDAC1, HDAC2, E47 and empty vector controls in mouse skeletal myoblasts or myotubes GSE38236: RNA-Seq of si-Snai1, si-Snai2, si-Snai1/2 and si-Scrambled treated myoblasts Refer to individual Series
Project description:Proteomics of carboxylated polystyrene bead (1.0 um) phagosomes from murine bone marrow-derived macrophages. cells were either resting or treated with 100 U/ml IFN-γ (PeproTech) and 100 ng/ml LPS (Sigma) for 24 h, 20 ng/ml Interleukin-4 (IL4) (BD Pharmingen) for 48 h, 20 ng/ml Interleukin-13 (IL13), 10 ng/ml Interleukin-10 (IL10)for 48 h or Reprogrammed (IL4 was incubated with BMDMs for 24 h, and the medium was replaced with fresh medium containing IFN-γ/LPS to incubate for another 24 h). Phagosomes were isolated after 30 min bead inoculation.
Project description:We developed a new sequencing assay to track the de novo deposition of the histone H3 variants H3.1 and H3.3 during S phase. We use cells stably expressing H3.1-SNAP or H3.3-SNAP, and synchronize them in G1/S by double-thymidine block. The SNAP-tag enables to discriminate newly synthesized histones from preexisting ones, via a quench-chase-capture strategy. We applied this strategy to isolate new H3.1 and H3.3 after releasing cells into S phase, and probed their distribution by MNase digestion and sequencing. We could thus characterize H3.1 and H3.3 dynamics from early to mid S phase at genome-wide resolution. We further applied our method to investigate the consequences of perturbations upon deletion of the H3.3 chaperone HIRA. We used HIRA knockout and control cells, and compared H3.1 and H3.3 distribution to early replication patterns by EdU labeling and sequencing of nascent DNA.
Project description:This SuperSeries is composed of the following subset Series: GSE25064: ChIP-Seq of Pax7 and Pax3 in myoblasts GSE32266: Mouse Myoblast Pax3, Pax7 overexpression and control Refer to individual Series
Project description:A comparative ChIP-chip analysis of TFIIB and NC2 in human B cells reveals that basal core promoter architectures control the equilibrium between NC2 and preinitiation complexes. We conducted a comparative ChIP-chip and gene expression analysis of TFIIB in human B cells and analyze associated core promoter architectures. TFIIB occupancy relates well to gene expression, with the vast majority of promoters being GC-rich and lacking defined core promoter elements. TATA consensus and TATA-like motifs but not the previously in vitro defined TFIIB recognition elements (BREs) are enriched in approximately 5% of the genes. Further insight was obtained by performing a parallel ChIP-chip analysis of the TFIIB antagonist NC2. The latter identifies a highly related target gene set. Nonetheless, subpopulations show strong variations in TFIIB/NC2 ratios, with high NC2/TFIIB ratios correlating to promoters that show dispersed transcription start site patterns and lacking defined core elements. Conversely, high TFIIB/NC2 ratios select for conserved core promoter elements that include TATA and INR (initiator), the upstream TFIIB recognition element (BREu) and the downstream promoter element (DPE). Two biological samples from LCL 721 lymphoblastoid human B cells were subjected to ChIP-chip analysis of TFIIB and NC2 using a Nimblegen human promoter array (based on the HG17 genome build) covering 1.5 kb DNA around transcription start sites.
Project description:A Scalable Epitope Tagging Approach for High Throughput ChIP-seq Analysis ChIP-seq comparison between CRISPR editing cells using epitope antibody and non-editing cells using endogeneous TF antibody