Project description:We report the IFN-induced dynamics in murine splenic B cells. Male C57BL/6 mice were injected subcutaneously with 10,000U IFNa and spleens were removed at 90min. B cells were negatively isolated using magnetic beads and profiled for the chromatin configuration by ATAC-seq. Profilings of chromatin configuration by ATAC-seq (0 and 90min, biological duplicate for each).
Project description:We report the IFN-induced dynamics in murine splenic B cells. Male C57BL/6 mice were injected subcutaneously with 10,000U IFNa and spleens were removed at designated time. B cells were negatively isolated using magnetic beads and profiled for the binding of PolII and Stat2 by ChIP-seq analysis. Profilings by PolII ChIP-seq over the time course (0, 0.5, 1, 2, 4, 8, 24 and 48hrs, single replicate for each), Stat2 ChIP-seq (0 and 90min, biological duplicate for each).
Project description:Differential gene transcription enables development and homeostasis in all animals and is regulated by two major classes of distal cis-regulatory DNA elements (CREs), enhancers and silencers. While enhancers have been thoroughly characterized, the properties and mechansisms of silencers remain largely unknown. By an unbiased genome-wide functional screen in Drosophila melanogaster S2 cells, we discover a class of silencers that bind one of three transcription factors (TFs) and are generally not included in chromatin-defined CRE catalogs, as they mostly lack detectable DNA accessibility. The silencer-binding TF CG11247, which we term Saft, safeguards cell fate decisions in vivo and functions via a highly-conserved domain we term ZAC and the corepressor G9a, independently of G9a’s H3K9-methyltransferase activity. Overall, our identification of silencers with unexpected properties and mechanisms has important implications for the understanding and future study of repressive CREs, as well as the functional annotation of animal genomes.
Project description:MicroRNA-155 (miR-155) is upregulated in primary effector CD8 T cells but is expressed at low amounts in naïve cells. Anti-viral CD8 T cell responses and viral clearance were impaired in miR-155 deficient (bic-/-) mice, and this defect was intrinsic to CD8 T cells, as adoptively transferred bic-/- CD8 T cells generated greatly reduced primary and memory responses during infection. To understand the mechanism by which miR-155 regulates CD8 T cell activation, we analyzed the gene expression profiles of naive and in vitro activated wild-type and bic-/- CD8 T cells. CD8 T cells were purified from uninfected C57BL/6 mice and stimulated in vitro with plate-bound anti-CD3 and anti-CD28 antibodies for 48 h or left unstimulated. RNA from these CD8 T cells was processed, amplified, labeled, and hybridized to Affymetrix GeneChip MoGene 1.0 st microarrays.
Project description:Interplays among lineage specific nuclear proteins, chromatin modifying enzymes and the basal transcription machinery govern cellular differentiation, but their dynamics of actions and coordination with transcriptional control are not fully understood. Alterations in chromatin structure appear to establish a permissive state for gene activation at some loci but they play an integral role in activation at other loci. To determine the predominant roles of chromatin states and factor occupancy in directing gene regulation during differentiation, we mapped chromatin accessibility, histone modifications, and nuclear factor occupancy genome-wide during mouse erythroid differentiation dependent on the master regulatory transcription factor GATA1. Remarkably, despite extensive changes in gene expression, the chromatin state profiles (proportions of a gene in a chromatin state dominated by activating or repressive histone modifications) and accessibility remain largely unchanged during GATA1-induced erythroid differentiation. In contrast, gene induction and repression are strongly associated with changes in patterns of transcription factor occupancy. Our results indicate that during erythroid differentiation, the broad features of chromatin states are established at the stage of lineage commitment, largely independently of GATA1. These determine permissiveness for expression, with subsequent induction or repression mediated by distinctive combinations of transcription factors. Using ChIP-Seq technology to examine DNase hypersensitivity, three transcription factors, and four histone modifications in Gata1-null murine G1E line and rescued G1E-ER4 subline, and also two of the transcription factors in mouse primary erythroblasts. ChIP input DNA was sequenced in each cell type as controls.
Project description:Comparison of Stat3 downstream gene expression in tumor-infiltraing myeloid cells. cDNA from sample was added into the array plate containing primer of specific genes related to angiogensis and gene expression level was analyzed by real-time PCR. The array plate was purchased from SA Bioscience and catalog number is PAMM-024 (mouse angiogenesis PCR array)
Project description:Whole transcriptome sequencing of B. phytofirmans PsJN colonizing potato (Solanum tuberosum L.) plants was used to analyze in planta gene activity and in the response of strain PsJN to plant stress in three different time points. The transcriptome of PsJN colonizing in vitro potato plants showed a broad array of functionalities encoded on the genome of strain PsJN. Our study indicates that endophytic B. phytofirmans PsJN cells are active inside plants. Moreover, the activity of strain PsJN is affected by plant drought stress, it senses plant stress signals and adjusts its gene expression accordingly.
Project description:Purpose: to characterize epigenetic changes following Twist1 mediated Epithelial-Mesenchymal Transition in human Methods: we characterized the epigenetic and transcriptome landscapes using whole genome transcriptome analysis by RNA-seq, DNA methylation by digital restriction enzyme analysis of methylation (DREAM) and histone modifications by CHIP-seq of H3K4me3 and H3K27me3 in immortalized human mammary epithelial cells relative to cells induced to undergo EMT by Twist1. Results: EMT is accompanied by focal hypermethylation and widespread global DNA hypomethylation, predominantly within transcriptionally repressed gene bodies. At the chromatin level, the number of gene promoters marked by H3K4me3 increases by more than one fifth; H3K27me3 undergoes dynamic genomic redistribution characterized by loss at half of gene promoters and overall reduction of peak size by almost one-half. This is paralleled by increased phosphorylation of EZH2 at serine 21. Among genes with highly altered mRNA expression, 23.1% switch between H3K4me3 and H3K27me3 marks, and those point to the master EMT targets and regulators CDH1, PDGFRA and ESRP1. Strikingly, Twist1 increases the number of bivalent genes by more than two fold. Inhibition of the H3K27 methyltransferases EZH2 and EZH1, which form part of the PRC2 complex, results in blocking EMT and stemness properties. Conclusion: Our findings demonstrate that the EMT program requires epigenetic remodeling by the Polycomb/Trithorax complexes leading to increased cellular plasticity which suggests that its inhibition will prevent EMT, and the associated breast cancer metastasis. DREAM profiles of human mammary epithelial cells before (HMLE_parental) and after Twist1 transfection (HMLE_Twist) were generated in monolayer (HMLE_Twist2D) and sphere culture by deep sequencing using Illumina GAIIx or Illumina hiseq2000. Furthermore, DREAM profile was also obtained in parental human mammary epithelial cells transfected with GFP