This SuperSeries is composed of the SubSeries listed below.
Identifying Nuclear Matrix-Attached DNA Across the Genome.
Specimen part, Cell line
View SamplesExperimental approaches to define the relationship between gene expression and nuclear matrix attachment regions (MARs) have given contrasting and method-specific results. We have developed a next generation sequencing strategy to identify MARs across the human genome (MAR-Seq). The method is based on crosslinking chromatin to its nuclear matrix attachment sites to minimize changes during biochemical processing. We used this method to compare nuclear matrix organization in MCF-10A mammary epithelial-like cells and MDA-MB-231 breast cancer cells and evaluated the results in the context of global gene expression (array analysis) and positional enrichment of gene-regulatory histone modifications (ChIP-Seq). In the normal-like cells, nuclear matrixattached DNA was enriched in expressed genes, while in the breast cancer cells, it was enriched in non-expressed genes. In both cell lines, the chromatin modifications that mark transcriptional activation or repression were appropriately associated with gene expression. Using this new MAR-Seq approach, we provide the first genome-wide characterization of nuclear matrix attachment in mammalian cells and reveal that the nuclear matrixassociated genome is highly cell-context dependent.
Identifying Nuclear Matrix-Attached DNA Across the Genome.
Specimen part, Cell line
View SamplesThe weekly turnover of the intestinal epithelium is driven by multipotent, Lgr5+, crypt base columnar cells (CBCs). In response to injury, however, Lgr5+ cells are lost but then re-emerge and are required for successful recovery. How these resurgent Lgr5+ stem cells arise is unclear. We transcriptionally profiled single cells from regenerating intestinal epithelia and identified a unique cell type we term the revival stem cell (rSC). rSCs are mutually exclusive to CBCs and are distinguished by elevated expression of cell survival and DNA repair genes. In homeostasis, rSCs are extremely rare, but nevertheless give rise to all the major cell types of the intestine including crypt-villus axes. After damage rSCs display a 20-fold, Yap-dependent, transient expansion, reconstitute the Lgr5+ CBC compartment and are required to regenerate a functional intestine. These studies define a unique stem cell phenotype that is mobilized by damage to reconstitute the intestinal epithelium. Overall design: Examination of regenerating mouse intestinal epithelium.
Single-cell transcriptomes of the regenerating intestine reveal a revival stem cell.
Specimen part, Cell line, Treatment, Subject
View SamplesThese RNA-seq data were generated to correlate with genomic interaction data in a related Hi-C analysis. MCF10A is a normal-like mammary epithelial cell line and MCF7 is a transformed estrogen responsive breast cancer cell line derived from a metastatic site; both are commonly used in models of breast cancer progression. Analysis revealed a set of genes related to repression of WNT signalling that were both up-regulated in MCF7 and located in genomic regions that had transitioned from closed to open structure in MCF7. Overall design: RNA-seq of MCF10A and MCF7 cells. 3 replicates each. Sequencing was strand-specific and conducted on ribo-depleted RNA.
Chromatin interaction analysis reveals changes in small chromosome and telomere clustering between epithelial and breast cancer cells.
No sample metadata fields
View SamplesCanonical Wnt signaling output is mediated by ß-catenin, which interacts with LEF/TCF transcription factors and recruits a general transcriptional activation complex to its C-terminus. Its N-terminus binds BCL9/9L proteins, which bind co-activators that in mammals contribute to fine-tuning the transcriptional output. We found that a BCL9/9L-dependent gene expression signature was strongly associated with patient outcome in colorectal cancer and that stem cell and mesenchymal genes determine its prognostic value. Abrogating BCL9/9L-ß-catenin signaling in independent mouse colorectal cancer models resulted in virtual loss of these traits, and oncogenic intestinal organoids lacking BCL9/9L proteins proved no longer tumorigenic. Our findings suggest that the BCL9/9L arm of Wnt-ß-catenin signaling sustains a stemness-to-differentiation equilibrium in colorectal cancer, which critically affects disease outcome. Mutational activation of the Wnt pathway is a key oncogenic event in colorectal cancer. Targeting the pathway downstream of activating mutations is challenging, and the therapeutic window is limited by intestinal toxicity. Contrasting with phenotypes caused by inactivating key Wnt pathway components, ablation of BCL9/9L proteins in adult mice indicated that they were dispensable for intestinal homeostasis, consistent with their role in tuning transcription. Cancer stem cells are increasingly recognized as responsible for tumor recurrence. The correlation between stemness traits in colorectal cancer models and BCL9/9L-ß-catenin signaling suggests that high Wnt signaling output is required for their maintenance. Our findings suggest that pruning Wnt-ß-catenin signaling might be well tolerated and prove sufficient for trimming stemness traits and improving disease outcome. Overall design: Examination of Bcl9/9l-knockout versus wild-type transcriptome in murine AOM-DSS tumors, APC-Kras tumors and healthy colocyte extracts.
BCL9/9L-β-catenin Signaling is Associated With Poor Outcome in Colorectal Cancer.
No sample metadata fields
View SamplesThe goal of the experiment was to determine the transcriptional expression profile of zebrafish thrombocytes in order to enable comparison with mouse and human platelets. Overall design: Thrombocyte isolation from Tg(cd41:EGFP) zebrafish peripheral blood was performed using a novel monoclonal antibody (3H9) to Cd41
Sorting zebrafish thrombocyte lineage cells with a Cd41 monoclonal antibody enriches hematopoietic stem cell activity.
No sample metadata fields
View SamplesDuring activation, T cells integrate multiple signals from APCs and cytokine milieu. The blockade of these signals can have clinical benefits as exemplified by CTLA4-Ig, which blocks interaction of B7 co-stimulatory molecules on APCs with CD28 on T cells. Variants of CTLA4-Ig, abatacept and belatacept are FDA approved as immunosuppressive agents in arthritis and transplantation whereas murine studies suggested that CTLA4-Ig can be beneficial in a number of other diseases. However, detailed analysis of human CD4 cell hyporesponsivness induced by CTLA4-Ig has not been performed. Herein, we established a model to study effect of CTLA4-Ig on the activation of human naïve T cells in a human mixed lymphocytes system. Comparison of human CD4 cells activated in the presence or absence of CTLA4-Ig, showed that co-stimulation blockade during TCR activation does not affect NFAT signaling but results in decreased activation of NF-kB and AP-1 transcription factors followed by profound decrease in proliferation and cytokine production. The resulting T cells become hyporesponsive to secondary activation and, although capable of receiving TCR signals, fail to proliferate or produce cytokines, demonstrating properties of anergic cells. However, unlike some models of T cell anergy, these cells did not possess increased levels of TCR signaling inhibitor CBLB. Rather, the CTLA4-Ig induced hyporesponsiveness was associated with an elevated level of p27kip1 cyclin-dependent kinase inhibitor. Overall design: Time series. Human resting and activated T cell dUTP mRNA-Seq profiles were generated on Illumina HiSeq2500
Functional characterization of human T cell hyporesponsiveness induced by CTLA4-Ig.
No sample metadata fields
View SamplesThe development of CRISPR-Cas systems for targeting DNA and RNA in diverse organisms has transformed biotechnology and biological research. Moreover, the CRISPR revolution has highlighted bacterial adaptive immune systems as a rich and largely unexplored frontier for discovery of new genome engineering technologies. In particular, the class 2 CRISPR-Cas systems, which use single RNA-guided DNA-targeting nucleases such as Cas9, have been widely applied for targeting DNA sequences in eukaryotic genomes. Here, we report DNA-targeting and transcriptional control with class I CRISPR-Cas systems. Specifically, we repurpose the effector complex from type I variants of class 1 CRISPR-Cas systems, the most prevalent CRISPR loci in nature, that target DNA via a multi-component RNA-guided complex termed Cascade. We validate Cascade expression, complex formation, and nuclear localization in human cells and demonstrate programmable CRISPR RNA (crRNA)-mediated targeting of specific loci in the human genome. By tethering transactivation domains to Cascade, we modulate the expression of targeted chromosomal genes in both human cells and plants. This study expands the toolbox for engineering eukaryotic genomes and establishes Cascade as a novel CRISPR-based technology for targeted eukaryotic gene regulation. Overall design: Examination of transcriptome-wide changes in gene expression with Cascade-mediated activation of endogenous genes.
Targeted transcriptional modulation with type I CRISPR-Cas systems in human cells.
Specimen part, Cell line, Subject
View SamplesGametogenesis is dependent on the expression of germline-specific genes. However, it remains unknown how the germline epigenome is distinctly established from that of somatic lineages. Here we show that genes commonly expressed in somatic lineages and spermatogenesis-progenitor cells undergo repression in a genome-wide manner in late stages of the male germline and identify underlying mechanisms. SCML2, a germline-specific subunit of a Polycomb repressive complex 1 (PRC1), establishes the unique epigenome of the male germline through two distinct antithetical mechanisms. SCML2 works with PRC1 and promotes RNF2-dependent ubiquitination of H2A, thereby marking somatic/progenitor genes on autosomes for repression. Paradoxically, SCML2 also prevents RNF2-dependent ubiquitination of H2A on sex chromosomes during meiosis, thereby enabling unique epigenetic programming of sex chromosomes for male reproduction. Our results reveal divergent mechanisms involving a shared regulator by which the male germline epigenome is distinguished from that of the soma and progenitor cells. Overall design: RNA-seq and ChIP-seq analyses using wild-type and Scml2-KO spermatogenic cells
Poised chromatin and bivalent domains facilitate the mitosis-to-meiosis transition in the male germline.
No sample metadata fields
View SamplesPrevalence and severity of allergic diseases have increased worldwide. To date, respiratory allergy phenotypes are not fully characterized and, in addition, the mechanisms underlying sublingual immunotherapy (SLIT) are still unknown.
Exploring novel systemic biomarker approaches in grass-pollen sublingual immunotherapy using omics.
Specimen part, Treatment, Time
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