Project description:The chromatin remodeller p400 has oncogenic properties that promote early steps of colon cancer. Chromatin immunoprecipitation (ChIP) of p400 together with chromatin profiling by ChIP-on-chip analysis demonstrated that p400 directly binds the chromatin at promoters of p400 target genes. Study of p400 binding on promoters of HCT116 cells
Project description:Chip-chip from pro-T(DN) cells from Rag1KO mice for H3K27ac, P300 and FAIRE The primary antigen receptor repertoire is sculpted by the process of V(D)J recombination, which must strike a balance between diversification and favoring gene segments with specialized functions. The precise determinants of how often gene segments are chosen to complete variable region coding exons remain elusive. We have quantified Vβ usage in the pre-selection Tcrb repertoire and report relative contributions of 14 distinct features in shaping their recombination efficiencies, including transcription, chromatin environment, spatial proximity to their DβJβ targets, and quality of recombinase recognition elements. Computational analyses provide a unifying model, revealing a minimal set of eight parameters that are predictive of Vβusage, dominated by chromatin modifications associated with transcription, but largely independent of the precise spatial proximity to DβJβclusters. Rag1KO DN epigenetic landscape at Tcrb
Project description:Chip-chip from pro-B cells from Rag1KO mice for H3K27ac and RNA Pol II Identification of novel enhancers from Ig heavy and light chain loci Rag1KO pro-B epigenetic landscape at Ig heavy and light chain loci
Project description:In humans, there are four Ago proteins (Ago1–4) and AGO1- and 2 were previously implicated in TGS induced by exogenous siRNAs and microRNAs (miRs) directed against gene promoter transcripts via promotion of changes in histone covalent modifications and DNA methylation. Not-with-standing, many mechanistic details of this process remain poorly defined in human cells, and very little is known about the identity of possible endogenous signals, which may drive this process in human cells. Given the evolutionary conserved role of siRNAs and AGO proteins in TGS and heterochromatin formation, we set out to analyse their possible involvement in senesence-associated repression of E2F target genes. To determine, in an unbiased manner, which genes might be under the control of AGO proteins we perfomed genome-wide promoter profiling in senescent and presenescent control WI38 primary fibroblasts applying “ChIP-on-chip” technology using 4 an anti-pan-AGO antibody. DNA from matched genomic inputs and chromatin immunoprecipitation (ChIP) samples were purified, amplified by PCR, and labeled either with Cy3 or Cy5 fluorophores. The labeled DNA from input and ChIP fractions were then combined and hybridised to human promoter arrays containing ~59,000 promoters. determination of AGO binding sites in WI-38 pre-senescent human fibroblast and in senescent human fibroblast
Project description:Epigenetic changes commonly occur in hepatocellular carcinoma (HCC) and are associated with aberrant gene expression. Recently, we demonstrated the pivotal role of abnormal H3K4me3 methylation, which is catalyzed by the menin/MLL, a TrxG family, in HCC development. Meanwhile, there is clear evidence that increasing global levels of H3K27me3 are activated in human primary HCC. To further elucidate the functional relatedness of the active H3K4me3 and repressive H3K27me3 histone remodeling in HCC, we performed H3K4me3 and H3K27me3 ChIP-on-chip screen using three HCC specimens and their adjacent tissues. Comparison of ChIP-on-chip results between tumor(C) and adjacent tissues(N) from three HCC specimens with H3K4me3
Project description:Polycomb group (PcG) proteins including EZH2, SUZ12 and so on, which specifically catalyze trimethylation of histone 3 lysine 27 (H3K27me3), and methylated H3K27 can be recognized by other specific binding proteins to compress chromatin structure, leading to the transcriptional repression of the target genes. To completely understand the epigenetic profile and molecular network of PcG in HCC, we performed ChIP-on-chip screens with EZH2, SUZ12 and H3K27me3 antibodies in HepG2 cells. Comparison of ChIP-on-chip results from EZH2, SUZ12 and H3K27me3.
Project description:Epigenetic changes commonly occur in hepatocellular carcinoma (HCC) and are associated with aberrant gene expression. Recently, we demonstrated the pivotal role of abnormal H3K4me3 methylation, which is catalyzed by the menin/MLL, a TrxG family, in HCC development. Meanwhile, there is clear evidence that increasing global levels of H3K27me3 are activated in human primary HCC. To further elucidate the functional relatedness of the repressive H3K27me3 and active H3K4me3 histone remodeling in HCC, we performed H3K27me3 and H3K4me3 ChIP-on-chip screen using three HCC specimens and their adjacent tissues. Comparison of ChIP-on-chip results between tumor(C) and adjacent tissues(N) from three HCC specimens with H3K27me3
Project description:ERG is a transcription factor that is involved in leukomogenesis and its mRNA overexpression has been associated with poor prognosis in a subset of patients with T-cell acute lymphoblastic leukemia (T-ALL) and acute myeloid leukemia (AML). Herein, a genome-wide screen of ERG target genes was conducted by chromatin immunoprecipitation-on-chip (ChIP-chip) in Jurkat cells. 342 significant annotated regions were derived from ChIP-chip experiments. Seventeen candidate promoter regions resulted in at least two-fold enrichment by quantitative PCR. Notably, ERG potential targets included WNT signaling genes: WNT2, WNT9A, WNT11, CCND1, and FZD7. Functionally, expression of WNT11 was downregulated with siRNA ERG knockdown and substantially upregulated in a tet-on ERG-inducible assay in K562 cells. To investigate a role for ERG in WNT signaling, a WNT agonist was used to inhibit glycogen synthase kinase (GSK-3). This treatment resulted in an ERG-dependent proliferative growth advantage in the tet-on ERG-inducible system. Lastly, chromatin immunoprecipitation assays of primary leukemia blasts confirmed WNT11 promoter enrichment dependent on ERG mRNA expression. In conclusion, ERG transcriptional networks in leukemia are revealed. Specifically, WNT11 emerged as a target of ERG. We propose that overexpression of ERG in acute leukemia may lead to a proliferative advantage upon activation of WNT signals. ChIP-chip with ERG antibody C20 and combined C17/20 and nonspecificic IgG in Jurkat
Project description:The transcription factor Pax5 represses B-lineage-inappropriate genes and activates B-cell-specific genes in B-lymphocytes. Here we have identified 170 novel Pax5-activated genes. Conditional mutagenesis demonstrated that the Pax5-regulated genes require continuous Pax5 activity for normal expression in pro-B and mature B cells. Expression of half of the Pax5-activated genes is either absent or significantly reduced upon Pax5 loss in plasma cells. Direct Pax5 target genes were identified based on their protein synthesis-independent activation by a Pax5-estrogen receptor fusion protein. Chromatin immunoprecipitation (ChIP) of Pax5 together with chromatin profiling by ChIP-on-chip analysis demonstrated that Pax5 directly activates the chromatin at promoters or putative enhancers of Pax5 target genes. The novel Pax5-activated genes code for key regulatory and structural proteins involved in B cell signaling, adhesion, migration, antigen presentation and germinal center B cell formation, thus revealing a complex regulatory network, which is activated by Pax5 to control B cell development and function. Keywords: Chip-chip, cell type comparison comparison of Pax5-/-Rag2-/- vs Rag2-/- pro-B cells
Project description:The transcription factor Pax5 represses B-lineage-inappropriate genes and activates B-cell-specific genes in B-lymphocytes. Here we have identified 170 novel Pax5-activated genes. Conditional mutagenesis demonstrated that the Pax5-regulated genes require continuous Pax5 activity for normal expression in pro-B and mature B cells. Expression of half of the Pax5-activated genes is either absent or significantly reduced upon Pax5 loss in plasma cells. Direct Pax5 target genes were identified based on their protein synthesis-independent activation by a Pax5-estrogen receptor fusion protein. Chromatin immunoprecipitation (ChIP) of Pax5 together with chromatin profiling by ChIP-on-chip analysis demonstrated that Pax5 directly activates the chromatin at promoters or putative enhancers of Pax5 target genes. The novel Pax5-activated genes code for key regulatory and structural proteins involved in B cell signaling, adhesion, migration, antigen presentation and germinal center B cell formation, thus revealing a complex regulatory network, which is activated by Pax5 to control B cell development and function. Keywords: Chip-chip, cell type comparison comparison of Pax5-/-Rag2-/- vs Rag2-/- pro-B cells