Hi-C of Drosophila embryos to investigate chromatin conformation during dorsal-ventral patterning
ABSTRACT: Hi-C was carried out for control embryos and embryos produced from gd7, Tollrm9/rm10, and Toll10B mutant mothers. The embryos from mutant mothers produce only a single type along the dorsal-ventral axis. We used these embryos to compare chromatin conformation across tissues.
Project description:In this experiment, we've examined chromatin conformation of OG2 (B6; CBA-Tg(Pou5f1-EGFP)2Mnn/J; stock number 004654) mouse stem cells cultured as described in (Shi et al., 2008), using different amounts of starting cells. We performed a modified in situ Hi-C protocol for 6 samples digested with MboI restriction enzyme having as starting material 1 million (M), 100 thousand (k), 50k, 25k, 10k or 1k cells. As well as, to 2 samples digested with HindIII restriction enzyme that had as starting material 5M or 100k cells. Traditional in situ Hi-C protocols recommend 5-10 million starting cells. The aim of the experiment was to assess the impact of decreasing the cell number on reproducibility, library complexity, chromatin structure visualization in order to adapt the method to the study of rare cell populations. Furthermore, we have characterised the 3D structure of peripheral blood mononuclear cells (PBMCs) obtained from a blood extraction from a healthy donor and from a lymph node biopsy from a DLBCL patient as a proof of concept for the suitability of Low-C for rare cell population analysis.
Project description:In this experiment we examined higher order chromatin structure during early Drosophila melanogaster development. We performed in situ Hi-C for hand-sorted non-mitotic embryos at nuclear cycle number 12, 13 and 14, and for embryos at 3-4 hours post fertilisation. During this time in development, the zygotic genome is activated and zygotic transcription is taking place for the first time. To assess the impact of transcription on chromatin structure we injected the transcription inhibitors alpha-amanitin or triptolide before zygotic genome activation and performed Hi-C and ChIP-seq for RNA Pol II. Furthermore, we used Hi-C to study genome architecture in embryos lacking the transcription factor Zelda.
Project description:We found acetyl-CoA levels increase when cells are committed to growth. We also found 3 components of the SAGA complex, Spt7p, Sgf73p and Ada3p as well as histones are dynamically acetylated in tune with the acetyl-CoA levels. ChIP-seq study reveals SAGA and H3K9ac predominantly occupy growth genes at the OX growth phase of the yeast metabolic cycle indicating acetyl-CoA levels may drive growth gene transcription program through acetylation of these proteins. Examination of H3K9ac and SAGA binding over two timepoints using H3 and Input as controls
Project description:Chronic lymphocytic leukemia (CLL) is characterized by substantial clinical heterogeneity, despite relatively few genetic alterations. To provide a basis for studying epigenome deregulation in CLL, we established genome-wide chromatin accessibility maps for 88 CLL samples from 55 patients using the ATAC-seq assay, and we also performed ChIPmentation and RNA-seq profiling for ten representative samples. Based on the resulting dataset, we devised and applied a bioinformatic method that links chromatin profiles to clinical annotations. Our analysis identified sample-specific variation on top of a shared core of CLL regulatory regions. IGHV mutation status – which distinguishes the two major subtypes of CLL – was accurately predicted by the chromatin profiles, and gene regulatory networks inferred for IGHV-mutated vs. IGHV-unmutated samples identified characteristic differences between these two disease subtypes. In summary, we found widespread heterogeneity in the CLL chromatin landscape, established a community resource for studying epigenome deregulation in leukemia, and demonstrated the feasibility of chromatin accessibility mapping in cancer cohorts and clinical research. Genome-wide profiling of chromatin states and gene expression levels in 88 CLL samples from 55 individuals gave rise to 88 ATAC-seq profiles, 40 ChIPmentation profiles (10 samples, each with 3 different antibodies and matched immunoglobulin control), and 10 RNA-seq profiles. Raw sequence data has been deposited at the EBI's European Genome-phenome Archive (EGA) under the accession number EGAS00001001821 (controlled access to protect patient privacy).
Project description:Mutant GATA6 hPSCs were obtained by TALEN genome editing or re-programmed from patient fibroblasts. Along with wild-type H9 cells, these GATA6 mutant cell lines were differentiated into SOX17+/CXCR4+ endodermal cells (day 3). The purpose of this work was to study the role of GATA6 in the development of the human pancreas at a molecular level.
Project description:ChIP-seq experiment for histone H3 and H3K4me3 from wild-type Saccharomyces cerevisiae (WT) and strains in which H3K14 has been substituted for alanine (K14A) or H3P16 has been substituted with valine (P16V).
Project description:Under continuous, glucose-limited conditions, budding yeast exhibit robust metabolic cycles associated with major oscillations of gene expression and metabolic state. However, how such fluctuations might be coordinately linked to changes in chromatin status is less well understood. Here, we examine the correlated genome-wide transcription and chromatin states across the yeast metabolic cycle (YMC) at unprecedented temporal resolution, revealing a "just in time supply chain" by which specific cellular processes such as ribosome biogenesis are coordinated in time with remarkable precision. We identify distinct chromatin and splicing patterns associated with different gene categories and determine the relative timing of chromatin modifications to maximal transcription. Additionally, we interrogate chromatin modifier occupancy and observe subtly distinct spatial and temporal patterns compared to the modifications themselves. Furthermore, we identify multiple lysine mutants in H3 or H4 tails that disrupt metabolic cycling, supporting a potentially cooperative role of histone modifications in the YMC. 16 time points RNA-seq and ChIP-seq of 8 histone marks over one metabolic cycle, 14 time points ChIP-seq of 3 chromatin modifiers over one metabolic cycle
Project description:To gain a better understanding of the transcription factors that regulate central carbon metabolism in Rhodobacter sphaeroides ChIP-seq was used to determine the genome-wide binding locations of 2 transcription factors: CceR (RSP_1663) and AkgR (RSP_0981) both predicted to be involved in the regulation of of central carbon and energy metabolism. Genome-wide protein-DNA interaction analysis of 2 transcription factors predicted to be involved in regulation of central carbon metabolism CceR and AkgR
Project description:To gain a deeper understanding of the transcription factors that regulate photosynthesis in Rhodobacter sphaeroides ChIP-seq was used to determine the genome-wide binding locations of 4 transcription factors (FnrL, PrrA, CrpK and RSP_2888) known or predicted to be involved in the regulation of photosynthesis. Genome-wide protein-DNA interaction analysis of 4 transcription factors known or predicted to be involved in the regulation of photosynthesis in Rhodobacter sphaeroides, using ChIP-seq and complementary assays.
Project description:By integrating sequence information from closely related bacteria with a compendium of high-throughput gene expression datasets, a large-scale transcriptional regulatory networks was constructed for Rhodobacter sphaeroides. Predictions from this network were validated in part using genome-wide analysis for 3 transcription factors (PpsR, RSP_0489 and RSP_3341). Genome-wide protein-DNA interaction analysis of 3 transcription factors predicted to be involved in photosynthesis (PpsR), carbon metabolism (RSP_0489) and iron homeostasis (RSP_3341) were used to validate predictions from a large-scale reconstruction of R. sphaeroides transcriptional regulatory network.