Elucidation of differential TF binding and epigenome in response to MYCi975.
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus Homo sapiens
PROVIDER: GSE178869 | GEO | 2022/04/27
REPOSITORIES: GEO
Similar Datasets
Project description:We investigated differences in the chromatin-binding profile of SOX18 (mouse) and its dominant-negative isoform SOX18RaOp, and how SOX18RaOp alters the binding location of SOX18. HeLa cells were transfected to generate 3 different conditions: 1. myc-SOX18, 2. myc-SOX18RaOp and 3. myc-SOX18 with untagged-SOX18RaOp. Each condition was performed in duplicate (6 samples total). An anti-Myc antibody was used to perform the pull-down. Background (input) was assessed by pooling cells transfected with each condition and sequencing without immunoprecipitation.
2021-08-30 | E-MTAB-10609 | biostudies-arrayexpress
Project description:MYC family proteins are oncogenic transcription factors that can globally affect the function of RNA Polymerase II (RNAPII). The ability of MYC proteins to promote transcription elongation depends on their ubiquitination, but the underlying mechanism and its biological relevance are unknown. Here we show that MYC and the Polymerase II associated factor, PAF1c, interact directly and their function is mutually dependent, since the specific binding of MYC to active promoters depends on PAF1c and, conversely, PAF1c is required for MYC-dependent pause release. Upon binding, PAF1c is rapidly transferred from MYC onto RNAPII and this transfer is driven by the HUWE1 ubiquitin ligase. Both MYC and HUWE1 globally control histone H2B ubiquitylation, which promotes transcriptional elongation and alters chromatin structure for double-strand break repair. Consistently, MYC suppresses the accumulation of double-strand breaks at promoters in response to topoisomerase II inhibition. While depletion of PAF1c has only minor effects on MYC-dependent gene expression, MYC induces rampant transcription-dependent DNA damage in PAF1c-depleted cells. We propose that the HUWE1-dependent transfer of PAF1c from MYC onto RNAPII is critical for absorbing the topological stress accompanied with deregulated and oncogenic transcription.
2021-02-15 | PXD023242 | Pride
Project description:Histone lysine acetylation and methylation regulate gene transcription through coordination of chromatin structure and transcriptional activity. However, our understanding of the role of histones in gene regulation is far from complete, in part due to newly discovered novel histone modifications, whose functions are yet to be uncovered1. Here we report that histone H3 lysine 27 crotonylation (H3K27cr) is selectively recognized by the YEATS domain of GAS41 in association with SIN3a-HDAC1/2 co-repressor complex for gene transcriptional repression. The GAS41 YEATS domain dimer binds proto-oncogenic transcription factor c-Myc, which recruits GAS41/SIN3a-HDAC1/2 complex to target gene loci in chromatin such as cell cycle inhibitor p21. Transcriptional de-repression of p21, directed by tumor suppressor p53 upon doxorubicin stimulation, entails dissociation of c-Myc/GAS41/SIN3a-HDAC1/2 complex from chromatin, reduced H3K27 crotonylation, and consequentially increased H3K27 acetylation at p21 locus. GAS41 knockout or H3K27cr binding depletion with CRISPR/Cas9 results in p21 activation, cell cycle arrest and tumor growth inhibition in mice. Our study explains mechanistically causal effect of GAS41 and c-Myc gene amplification on down-regulation of p21 in human colorectal cancer, and suggests GAS41 as an anti-cancer target. We propose that H3K27 crotonylation represents a previously unrecognized, distinct chromatin state for gene transcriptional repression in contrast to H3K27 trimethylation for long-term transcriptional silencing and H3K27 acetylation for transcriptional activation.
2023-10-03 | GSE128590 | GEO
Project description:The MYC oncogene encodes for the MYC protein and is frequently dysregulated across multiple cancer cell types, making it an attractive target for cancer therapy. MYC overexpression leads to MYC binding at active enhancers, resulting in a global transcriptional amplification of active genes. Since superenhancers are frequently dysregulated in cancer, we hypothesized that MYC preferentially invades into superenhancers and alters the cancer genome organization. To that end, we performed ChIP-seq, RNA-seq, 4C-seq and SIQHiC (Spike-in Quantitative Hi-C) on the U2OS osteosarcoma cell line with tetracycline-inducible MYC. MYC overexpression in U2OS cells modulated histone acetylation and increased MYC binding at superenhancers. SIQHiC analysis revealed increased global chromatin contact frequency, particularly at chromatin interactions connecting MYC binding sites at promoters and enhancers. Immunofluorescence staining showed that MYC molecules formed punctate foci at these transcriptionally active domains after MYC overexpression. These results demonstrate the accumulation of overexpressed MYC at promoter-enhancer hubs and suggest that MYC invades into enhancers through spatial proximity. At the same time, the increased protein-protein interactions may strengthen these chromatin interactions to increase chromatin contact frequency. CTCF siRNA knockdown in MYC overexpressed U2OS cells demonstrated that removal of architectural proteins can disperse MYC and abrogate the increase in chromatin contacts. By elucidating the chromatin landscape of MYC driven cancers, we can potentially target MYC associated chromatin interactions for cancer therapy.
2022-01-17 | GSE164777 | GEO
Project description:p300 is a histone acetyltransferase that associates with crucial biological processes. p300 acetylates all four histones in the nucleosome, a basic unit of chromatin, and alters chromatin structure and dynamics. In this study, we performed structural and biochemical analysis to understand the nucleosome binding by p300. Crosslinking mass spectrometry suggests that the p300 catalytic core binds to nucleosomes in multiple binding forms to acetylate different histone tails.
2022-06-29 | PXD033804 | JPOST Repository
Project description:PFA ependymomas are a lethal glial malignancy of the hindbrain found in babies and toddlers. Lacking any highly recurrent somatic mutations, PFAs have been proposed as a largely epigenetically driven tumor type. An almost complete lack of model systems has inhibited discovery of novel PFA therapies. Both in vitro and in vivo, the PFA hypoxic microenvironment controls the availability of specific metabolites to diminish histone methylation, and to increase both histone demethylation and acetylation at H3K27. PFA ependymoma initiates from a cell lineage in the first trimester of human development where there is a known hypoxic microenvironment. Unique to PFA cells, transient exposure to ambient oxygen results in irreversible cellular toxicity. PFA tumors exhibit a low basal level of H3K27me3, and paradoxically inhibition of H3K27 methylation shows significant and specific activity against PFA. Targeting metabolism and/or the epigenome presents a unique opportunity for rational therapy for infants with PFA ependymoma.
2020-08-13 | PXD018191 | Pride
Project description:Patients with diffuse midline gliomas-H3K27-altered (DMG) display a dismal prognosis. However, the molecular mechanisms underlying DMG tumorigenesis remain poorly defined. Here we show that SMARCA4, the catalytic subunit of mammalian SWI/SNF chromatin remodeling complex, is essential for the proliferation, migration and invasion of DMG cells and tumor growth in patient-derived DMG xenograft models. SMARCA4 co-localizes with SOX10 at gene regulatory elements (GRE) to control the expression of genes involved in cell growth and extracellular matrix (ECM). Moreover, SMARCA4 chromatin binding is reduced upon depletion of SOX10 or H3.3K27M, a mutation occurring in about 60% DMG tumors. Furthermore, the SMARCA4 occupancy at enhancers marked by both SOX10 and H3K27 acetylation is reduced the most upon depleting the H3.3K27M mutation. Taken together, our results support a model in which epigenome reprogramming by H3.3K27M creates a dependence on SMARCA4-mediated chromatin remodeling to drive gene expression and the pathogenesis of H3.3K27M DMG.
2022-09-02 | GSE185280 | GEO
Project description:MYC family proteins are oncogenic transcription factors that can globally affect the function of RNA Polymerase II (RNAPII). The ability of MYC proteins to promote transcription elongation depends on their ubiquitination, but the underlying mechanism and its biological relevance are unknown. Here we show that MYC and the Polymerase II associated factor, PAF1c, interact directly and their function is mutually dependent, since the specific binding of MYC to active promoters depends on PAF1c and, conversely, PAF1c is required for MYC-dependent pause release. Upon binding, PAF1c is rapidly transferred from MYC onto RNAPII and this transfer is driven by the HUWE1 ubiquitin ligase. Both MYC and HUWE1 globally control histone H2B ubiquitylation, which promotes transcriptional elongation and alters chromatin structure for double-strand break repair. Consistently, MYC suppresses the accumulation of double-strand breaks at promoters in response to topoisomerase II inhibition. While depletion of PAF1c has only minor effects on MYC-dependent gene expression, MYC induces rampant transcription-dependent DNA damage in PAF1c-depleted cells. We propose that the HUWE1-dependent transfer of PAF1c from MYC onto RNAPII is critical for absorbing the topological stress accompanied with deregulated and oncogenic transcription.
2021-02-10 | GSE150206 | GEO
Project description:MYC family proteins are oncogenic transcription factors that can globally affect the function of RNA Polymerase II (RNAPII). The ability of MYC proteins to promote transcription elongation depends on their ubiquitination, but the underlying mechanism and its biological relevance are unknown. Here we show that MYC and the Polymerase II associated factor, PAF1c, interact directly and their function is mutually dependent, since the specific binding of MYC to active promoters depends on PAF1c and, conversely, PAF1c is required for MYC-dependent pause release. Upon binding, PAF1c is rapidly transferred from MYC onto RNAPII and this transfer is driven by the HUWE1 ubiquitin ligase. Both MYC and HUWE1 globally control histone H2B ubiquitylation, which promotes transcriptional elongation and alters chromatin structure for double-strand break repair. Consistently, MYC suppresses the accumulation of double-strand breaks at promoters in response to topoisomerase II inhibition. While depletion of PAF1c has only minor effects on MYC-dependent gene expression, MYC induces rampant transcription-dependent DNA damage in PAF1c-depleted cells. We propose that the HUWE1-dependent transfer of PAF1c from MYC onto RNAPII is critical for absorbing the topological stress accompanied with deregulated and oncogenic transcription.
2021-02-10 | GSE150210 | GEO
Project description:MYC family proteins are oncogenic transcription factors that can globally affect the function of RNA Polymerase II (RNAPII). The ability of MYC proteins to promote transcription elongation depends on their ubiquitination, but the underlying mechanism and its biological relevance are unknown. Here we show that MYC and the Polymerase II associated factor, PAF1c, interact directly and their function is mutually dependent, since the specific binding of MYC to active promoters depends on PAF1c and, conversely, PAF1c is required for MYC-dependent pause release. Upon binding, PAF1c is rapidly transferred from MYC onto RNAPII and this transfer is driven by the HUWE1 ubiquitin ligase. Both MYC and HUWE1 globally control histone H2B ubiquitylation, which promotes transcriptional elongation and alters chromatin structure for double-strand break repair. Consistently, MYC suppresses the accumulation of double-strand breaks at promoters in response to topoisomerase II inhibition. While depletion of PAF1c has only minor effects on MYC-dependent gene expression, MYC induces rampant transcription-dependent DNA damage in PAF1c-depleted cells. We propose that the HUWE1-dependent transfer of PAF1c from MYC onto RNAPII is critical for absorbing the topological stress accompanied with deregulated and oncogenic transcription.
2021-02-10 | GSE150209 | GEO