PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Histone mark”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Differential inhibition of transcription of DNA by melanoma chromosomal proteins.

Histones and 4 nuclear nonhistone protein fractions (NHP1-4) were extracted from nuclei of a Cloudman mouse melanoma cell line (NCTC 3960, CCL 53) and tested for their ability to bind to DNA and influence transcription. The histones and NHP fractions showed different binding affinities for DNA, with the histones and NHP1 exhibiting the highest affinity. The NHP fractions differentially affected both the rate of RNA synthesis and the size of RNA transcribed. NHP1 which inhibited RNA synthesis to the greatest extent, inhibited synthesis of all sizes of RNA except for major peaks of 28S and 8S RNS and discrete minor peaks of 7S, 6S, 5S, and 4S RNS. Histones markedly enhanced the effect of NHP1 on RNA synthesis. These results suggest that there are nonhistone proteins in Cloudman melanoma nuclei which have a high affinity for DNA and which may be involved in the regulation of transcription.

Animals↗

Epigenetic regulation of transcription in intermediate heterochromatin.

Constitutive heterochromatin is a compact, transcriptionally inert structure formed in gene-poor and repeat- and transposon-rich regions. In Arabidopsis, constitutive heterochromatin is characterized by hypermethylated DNA and histone H3 dimethylated at lysine (K) 9 (H3K9me2) together with depletion of histone H3 dimethylated at lysine 4 (H3K4me2). Here, we describe loci with intermediate properties of heterochromatin in which transcription downregulation is inherited in a manner similar to constitutive heterochromatin, although the loci are associated with opposing histone marks--H3K4me2 and H3K9me2. In the ddm1 (decrease in DNA methylation 1) mutants, their transcriptional activation is accompanied by the expected shift in the H3 modifications--depletion of H3K9me2 and enrichment in H3K4me2. In mom1 (Morpheus' molecule 1) mutants, however, a marked increase in transcription is not accompanied by detectable changes in the levels of H3K4me2 and H3K9me2. Therefore, transcriptional regulation in the intermediate heterochromatin involves two distinct epigenetic mechanisms. Interestingly, silent transgenic inserts seem to acquire properties characteristic of the intermediate heterochromatin.

ATPases Associated with Diverse Cellular Activitie↗

Genome-wide analysis of polymerase III-transcribed Alu elements suggests cell-type-specific enhancer function.

Alu elements are one of the most successful families of transposons in the human genome. A portion of Alu elements is transcribed by RNA Pol III, whereas the remaining ones are part of Pol II transcripts. Because Alu elements are highly repetitive, it has been difficult to identify the Pol III-transcribed elements and quantify their expression levels. In this study, we generated high-resolution, long-genomic-span RAMPAGE data in 155 biosamples all with matching RNA-seq data and built an atlas of 17,249 Pol III-transcribed Alu elements. We further performed an integrative analysis on the ChIP-seq data of 10 histone marks and hundreds of transcription factors, whole-genome bisulfite sequencing data, ChIA-PET data, and functional data in several biosamples, and our results revealed that although the human-specific Alu elements are transcriptionally repressed, the older, expressed Alu elements may be exapted by the human host to function as cell-type-specific enhancers for their nearby protein-coding genes.

Alu Elements↗

H3K9ac promoter profiling and their association with gene expression in immune cells of T2-high asthma patients.

BACKGROUND: Asthma is a heterogeneous chronic inflammatory syndrome, with the T2-high endotype defined by robust type 2 immune responses and skewed T helper polarization. Although H3K9 acetylation (H3K9ac) is a key activating histone mark in T helper differentiation, its genome-wide promoter landscape in circulating immune cells of T2-high asthma remains uncharacterized. METHODS: Integrated ChIP-seq and RNA-seq profiling was performed on peripheral blood mononuclear cells (PBMCs) from ten T2-high asthma patients and ten healthy controls. Differential H3K9ac enrichment and gene expression were analyzed, followed by concordance and Spearman correlation analyses to identify genes under H3K9ac-linked transcriptional regulation. Findings were contextualized using publicly available H3K27ac ChIP-seq datasets from asthmatic airway tissue and glucocorticoid-treated airway epithelial cells. RESULTS: We identified 2340 differential enrichment regions (DERs), 95.9% mapping to promoters, with nearly all showing H3K9ac loss and enrichment in T cell receptor signaling and Th1/Th2/Th17 differentiation pathways. Genes encoding histone-modifying enzymes, including HATs, HDACs, and HMTs, were overrepresented, suggesting a self-reinforcing epigenetic feedback loop. Integrated analysis identified 979 genes with concordant H3K9ac and expression changes: downregulated genes were enriched in lymphocyte activation and TNF signaling, whereas upregulated genes were enriched in AKT and MAPK pathways. Locus-specific analyses showed H3K9ac loss at Th1/Th17 genes (TBX21, IFNG, CCR6) and gain at Th2 genes (IL4, TSLP). Targeted RT-qPCR provided independent experimental support for reduced expression of Th1-associated genes, with significant decreases in STAT1 and STAT4 in T2-high asthma patients. Correlation analysis identified six genes with significant H3K9ac-expression associations. CONCLUSIONS: Promoter H3K9ac remodeling is a defining epigenetic feature of T2-high asthma, reflecting coordinated alterations at T helper lineage-defining loci and inflammatory pathways.

Asthma↗

Chromatin-binding protein HMGN1 promotes HCC tumorigenesis via histone methylation-induced RALB transcriptional suppression.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide, with metastasis being the primary cause of its high mortality. The chromatin-binding protein, high mobility group nucleosome binding domain 1 (HMGN1), has been implicated in tumour progression, but its specific role and mechanism in HCC metastasis remain unclear. This study investigates the function of HMGN1 and its potential as a therapeutic target. Analysis of patient samples confirms an upregulation of HMGN1 in HCC tissues, correlating with advanced disease and poor prognosis. Functional assays demonstrate that HMGN1 promotes HCC metastasis in vitro and in vivo. Mechanistically, integrated RNA sequencing and chromatin immunoprecipitation sequencing analyses reveal that HMGN1 binds to the promoter of RAS-like proto-oncogene B (RALB) gene, recruiting the repressive histone mark H3K9me2 to epigenetically silence its transcription and drive metastasis. Therapeutically, a nanoparticle delivery system for siRNA against HMGN1 effectively silences its expression and inhibits metastasis in orthotopic liver xenograft tumour models. Our findings establish HMGN1 as a key epigenetic driver of HCC metastasis and highlight siRNA-nanoparticle targeting of HMGN1 as a promising precision therapeutic strategy.

Humans↗

Prenatal arsenic exposure alters EZH2-H3K27me3 occupancy at TNF-α promoter leading to insulin resistance and metabolic syndrome in a mouse model.

The global prevalence of Metabolic Syndrome (MetS) is continuously rising and exposure to environmental toxicants such as arsenic could be contributing to this rapid surge. In this study, we have assessed the effects of prenatal arsenic exposure on insulin resistance and MetS parameters in a mouse model, and an underlying mechanism was identified. We found that prenatal arsenic exposure promotes insulin resistance and adipocyte dysfunction which leads to the early onset of MetS in male offspring. Primary adipocytes isolated from 20-week-old arsenic-exposed offspring showed hypertrophy, elevated basal lipolysis, and impaired insulin response along with enhanced expression of Tumor necrosis factor-alpha (TNF-α). TNF-α levels were consistently high at gestational day 15.5 (GD15.5) as well as primary adipocytes of 6-week-old arsenic-exposed male offspring. Along with TNF-α, downstream p-JNK1/2 levels were also increased, which led to inhibitory phosphorylation of IRS1and reduced GLUT4 translocation upon insulin stimulation in adipocytes. Insulin response and downstream signaling were restored upon TNF-α inhibition, confirming its central role. The persistent overexpression of TNF-α in adipocytes of arsenic-exposed mice resulted from diminished EZH2 occupancy and reduced H3K27me3 (gene silencing histone marks) at the TNF-α promoter. This further led to chromatin relaxation, recruitment of c-Jun and CBP/p300, formation of an enhanceosome complex, and TNF-α expression. Our findings show how prenatal arsenic exposure can epigenetically modulate TNF-α expression to promote adipocyte dysfunction and insulin resistance which contributes to the early onset of MetS in offspring.

Animals↗

Dynamic association of H3K36me3 with pericentromeric heterochromatin regulates its replication time.

The flexibility of the spatio-temporal genome replication program during development and disease highlights the regulatory role of plastic epigenetic mechanisms over genetic determinants. Histone post-translational modifications are broadly implicated in replication timing control, yet the specific mechanisms through which individual histone marks influence replication dynamics, particularly in heterochromatin, remain unclear. Here, we demonstrate that H3K36me3 dynamically enriches at pericentromeric heterochromatin, composed of major satellite DNA repeats, prior to replication during mid S phase in mouse embryonic stem cells. By knocking down lysine 36-specific methyltransferases or by targeting the H3K36M oncohistone to pericentromeric heterochromatin, we reduce global or local H3K36me3 levels, respectively, revealing its essential role in preserving the replication timing of constitutive heterochromatin. Loss of H3K36me3 accompanies increased RNA polymerase II serine-5 phosphorylation and lowered major satellite RNA levels, indicating transcriptional dysregulation. Notably, we identify a strand-specific contribution of major satellite forward transcripts in regulating the replication timing of constitutive heterochromatin and maintaining chromatin stability, highlighting the importance of non-coding RNAs as critical regulators of replication timing.

Heterochromatin↗

Distinct roles of Polycomb group gene products in transcriptionally repressed and active domains of Hoxb8.

To address the molecular mechanisms underlying Polycomb group (PcG)-mediated repression of Hox gene expression, we have focused on the binding patterns of PcG gene products to the flanking regions of the Hoxb8 gene in expressing and non-expressing tissues. In parallel, we followed the distribution of histone marks of transcriptionally active H3 acetylated on lysine 9 (H3-K9) and methylated on lysine 4 (H3-K4), and of transcriptionally inactive chromatin trimethylated on lysine 27 (H3-K27). Chromatin immunoprecipitation revealed that the association of PcG proteins, and H3-K9 acetylation and H3-K27 trimethylation around Hoxb8 were distinct in tissues expressing and not expressing the gene. We show that developmental changes of these epigenetic marks temporally coincide with the misexpression of Hox genes in PcG mutants. Functional analyses, using mutant alleles impairing the PcG class 2 component Rnf2 or the Suz12 mutation decreasing H3-K27 trimethylation, revealed that interactions between class 1 and class 2 PcG complexes, mediated by trimethylated H3-K27, play decisive roles in the maintenance of Hox gene repression outside their expression domain. Within the expression domains, class 2 PcG complexes appeared to maintain the transcriptionally active status via profound regulation of H3-K9 acetylation. The present study indicates distinct roles for class 2 PcG complexes in transcriptionally repressed and active domains of Hoxb8 gene.

Animals↗

A two-step, PU.1-dependent mechanism for developmentally regulated chromatin remodeling and transcription of the c-fms gene.

Hematopoietic stem cells and multipotent progenitors exhibit low-level transcription and partial chromatin reorganization of myeloid cell-specific genes including the c-fms (csf1R) locus. Expression of the c-fms gene is dependent on the Ets family transcription factor PU.1 and is upregulated during myeloid differentiation, enabling committed macrophage precursors to respond to colony-stimulating factor 1. To analyze molecular mechanisms underlying the transcriptional priming and developmental upregulation of the c-fms gene, we have utilized myeloid progenitors lacking the transcription factor PU.1. PU.1 can bind to sites in both the c-fms promoter and the c-fms intronic regulatory element (FIRE enhancer). Unlike wild-type progenitors, the PU.1(-/-) cells are unable to express c-fms or initiate macrophage differentiation. When PU.1 was reexpressed in mutant progenitors, the chromatin structure of the c-fms promoter was rapidly reorganized. In contrast, assembly of transcription factors at FIRE, acquisition of active histone marks, and high levels of c-fms transcription occurred with significantly slower kinetics. We demonstrate that the reason for this differential activation was that PU.1 was required to promote induction and binding of a secondary transcription factor, Egr-2, which is important for FIRE enhancer activity. These data suggest that the c-fms promoter is maintained in a primed state by PU.1 in progenitor cells and that at FIRE PU.1 functions with another transcription factor to direct full activation of the c-fms locus in differentiated myeloid cells. The two-step mechanism of developmental gene activation that we describe here may be utilized to regulate gene activity in a variety of developmental pathways.

Animals↗

A cooperative regulatory module between TAGL2 and JMJC1 activates specific defense genes against root-knot nematodes in tomato.

Plant-parasitic nematodes (PPNs) threaten global food security. Although epigenetic modifications are crucial for plant immunity, how histone modifiers contribute to root-knot nematodes (RKNs, Meloidogyne incognita) resistance remains unclear. Here, using genetic, molecular and biochemical approaches, we investigated the epigenetic and transcriptional mechanisms underlying RKN resistance mediated by the histone demethylase (HDM) JMJC1 and the MADS-box transcription factor TAGL2 in tomato (Solanum lycopersicum). We identified JMJC1 as an RKN-induced positive defense regulator targeting H3K9me3 and H3K27me3 histone marks. JMJC1 physically interacts with TAGL2, which also positively regulates RKN resistance. Transcriptomic analysis indicated that TAGL2 regulates multiple layers of the plant defense network, transcriptionally activating representative genes from distinct pathways (including PUB10, bHLH98, CCaMK, and SAUR3), which we validated as positive regulators of RKN resistance via virus-induced gene silencing (VIGS). At the chromatin level, TAGL2 and JMJC1 co-regulate these loci, associating with localized H3K9me3 and H3K27me3 reduction. Furthermore, TAGL2 directly activates JMJC1 transcription, establishing a positive feedback loop that amplifies immune signaling. Our findings reveal a cooperative model wherein a HDM and a transcription factor coordinate at specific loci to fine-tune multiple defense layers at both epigenetic and transcriptional levels, providing insights for breeding durable nematode-resistant plants.

Solanum lycopersicum↗

The piRNA pathway mediates transcriptional silencing of LTR retrotransposons in ovaries and somatic tissues of Aedes mosquitoes.

The PIWI-interacting RNA (piRNA) pathway preserves genomic integrity by suppressing transposable elements in animal germlines. Despite its well-established function in the animal germline, piRNAs and PIWI proteins are expressed in somatic tissues across arthropod species, and their functions outside the gonads remain poorly understood. Aedes albopictus mosquitoes express four PIWI genes, Piwi4, Piwi5, Piwi6, and Ago3, in both gonadal and somatic tissues. Here, we generated Piwi6 knockout (KO) Ae. albopictus cell lines and observed a substantial upregulation of long terminal repeat retrotransposons, including a full-length endogenous retrovirus that we named Aedes albopictus Endogenous Retrovirus-1 (AalERV1). Nascent RNA sequencing and Cleavage Under Targets and Tagmentation (CUT&Tag) analyses revealed that Piwi6 silences AalERV1 transcriptionally by guiding the deposition of the repressive H3K9me3 histone mark. Consistently, Piwi6 localized to both the cytoplasm and nucleus, with sequences in the intrinsically disordered region guiding nuclear translocation. Reintroduction of full-length GFP-Piwi6, but not a mutant GFP-Piwi6 defective in nuclear localization, rescued AalERV1 repression in Piwi6 KO cells. Importantly, Piwi6-mediated control of AalERV1 was recapitulated in vivo as Piwi6 knockdown increased AalERV1 expression in both ovaries and somatic tissues of Ae. albopictus mosquitoes. These results establish Aedes mosquitoes as a model to study nuclear PIWI functions and suggest that somatic piRNA-mediated transposon silencing is evolutionarily conserved across arthropod species.

Animals↗

The human PAF complex coordinates transcription with events downstream of RNA synthesis.

The yeast PAF (yPAF) complex interacts with RNA polymerase II and coordinates the setting of histone marks associated with active transcription. We report the isolation and functional characterization of the human PAF (hPAF) complex. hPAF shares four subunits with yPAF (hCtr9, hPaf1, hLeo1, and hCdc73), but contains a novel higher eukaryotic-specific subunit, hSki8. RNAi against hSki8 or hCtr9 reduces the cellular levels of other hPAF subunits and of mono- and trimethylated H3-Lys 4 and dimethylated H3-Lys 79. The hSki8 subunit is also a component of the human SKI (hSKI) complex. Yeast SKI complex is cytoplasmic and together with Exosome mediates 3'-5' mRNA degradation. However, hSKI complex localizes to both nucleus and cytoplasm. Immunoprecipitation experiments revealed that hPAF and hSKI complexes interact, and ChIP experiments demonstrated that hSKI associates with transcriptionally active genes dependent on the presence of hPAF. Thus, in addition to coordinating events during transcription (initiation, promoter clearance, and elongation), hPAF also coordinates events in RNA quality control.

HeLa Cells↗

ELYS associates with distinct DNA sequence environments during post-mitotic nuclear pore reassembly.

Nuclear pore complexes (NPCs) contribute to genome organization and cell identity, yet how post-mitotic NPC assembly is coordinated with chromatin architecture remains unclear. Here, we show that the nucleoporin ELYS preferentially associates with chromatin regions displaying distinct intrinsic DNA sequence features that are not explained by the repressive histone marks examined here. ELYS-bound regions are enriched for AT-rich sequences, whereas ELYS binding at super-enhancer-associated loci shift toward GC-rich sequence composition, revealing distinct sequence environments. These findings indicate that ELYS localization is associated with distinct intrinsic DNA sequence features and suggest a mechanism by which nuclear pore-associated architecture restores transcriptional programs after mitosis.

Journal Article↗

Extrinsic heterogeneity: Collectivity in isotropic conformational fluctuations of chromosomes.

Eukaryotic interphase chromosomes maintain a three-dimensional conformation within the nucleus and undergo fluctuations. However, the analysis of chromosome conformational fluctuations has been mainly limited to chromosome conformation capture data that record the contact frequencies between chromosomal regions. Herein, we investigated chromosome fluctuations as polymers based on experimental data from sequential fluorescence in situ hybridization using a multiomics methodology. To describe the principal modes of chromosome fluctuations, we applied principal-component analysis to the three-dimensional conformation information of single chromosomes in 446 mouse embryonic stem cells obtained from sequential fluorescence in situ hybridization data analysis for spatial genomics and signals of nuclear factors (histone marks, repeat DNAs, and proteins in interchromosomal nuclear compartments). We found that chromosome fluctuations exhibit both isotropic and anisotropic modes. The isotropic conformational fluctuations of all chromosome types tended to synchronize each other, reflecting extrinsic heterogeneity in chromosome conformation that is independent of the cell cycle. In contrast, anisotropic conformational fluctuations, occurring in a spindle-like shape, were associated with the interactions between repeat DNAs and nuclear factors. These results highlight the importance of dissecting cell-cycle-independent nuclear organization based on the conformational folding of chromosomes and the interactions between genomic regions and nuclear factors.

Animals↗

Targeting SUV4-20H2-mediated H4K20 methylation restrains growth and migration in pediatric high-grade astrocytomas.

Pediatric astrocytomas are characterized by increased molecular and clinical heterogeneity with epigenetic alterations contributing to aggressiveness and therapy resistance. The repressive histone mark H4K20 trimethylation (H4K20me3) and the methyltransferase SUV4-20H2 (KMT5C) are critical regulators of chromatin integrity and genome stability, with limited investigation in pediatric astrocytomas. KMT5C mRNA levels were evaluated in a publicly available pediatric gliomas database using bioinformatic analysis. Investigation of SUV4-20H2 and H4K20me3 expression was performed in a cohort of 43 pediatric astrocytoma tissues by immunohistochemistry. Their functional role and mechanism of action was investigated in pediatric glioma cell lines by using the substrate-competitive inhibitor of SUV4-20, A-196. Cell viability, apoptosis and migration were assessed using XTT, cleaved PARP, and wound healing assays, respectively. Effects of treatment on H4K20 methylation, DNA damage, mitotic stress [Polo-like kinase (PLK1) expression], and invasion markers (N-cadherin, β-catenin expression) were examined by western immunoblotting. KMT5C mRNA was significantly enriched in pediatric high-grade astrocytomas compared to low-grade tumors. A significant elevation of SUV4-20H2 and H4K20me3 expression was detected in astrocytoma tissues indicating epigenetic dysregulation contributing to malignancy. Treatment with A-196 reduced cell proliferation of pediatric glioma cell lines and induced apoptosis in a dose-dependent manner. It further impaired cell migration, accompanied by reduced N-cadherin and β-catenin expression. Mechanistically, inhibition of SUV4-20 depleted H4K20me3, inducing chromatin destabilization, replication-associated DNA damage and was associated with increased PLK1 expression, consistent with activation of a mitotic stress response. Our findings indicate that SUV4-20H2-mediated H4K20 activity in pediatric high-grade astrocytomas maintains their growth and migratory potential by regulating chromatin integrity and may serve as potential therapeutic target.

H4K20me2/3↗

Tracing regulatory element networks using epigenetic traits to identify key transcription factors: TENET R/Bioconductor package.

SUMMARY: There is a lack of publicly available bioinformatic tools that can be widely used by researchers to identify transcription factors (TFs) that regulate cell type-specific regulatory elements (REs). To address this, we developed the Tracing regulatory Element Networks using Epigenetic Traits (TENET) R/Bioconductor package. By collecting hundreds of histone mark and open chromatin datasets from a variety of cell lines, primary cells, and tissues, and comparing these features along with matched DNA methylation and gene expression data, TENET identifies TFs and REs linked to a specific cell type. Moreover, we developed methods to interrogate findings using motifs, clinical information, and other genomic and chromatin conformation capture datasets, and applied them to pan-cancer data, highlighting TFs and REs associated with ten different cancer types. TENET enables researchers to better characterize the 3D epigenomes of cell types of interest for future clinical applications. AVAILABILITY AND IMPLEMENTATION: TENET is available at http://bioconductor.org/packages/TENET. Curated functional genomic datasets utilized by TENET are available at http://bioconductor.org/packages/TENET.AnnotationHub. Example datasets are available at http://bioconductor.org/packages/TENET.ExperimentHub.

Transcription Factors↗

BTS: a scalable Bayesian Tissue Score for prioritizing GWAS variants and their functional contexts across >1000s of omics datasets.

MOTIVATION: statistics from genome-wide association studies (GWAS) are widely used in fine-mapping and colocalization analyses to identify causal variants and their enrichment in functional contexts, such as affected cell types and genomic features. With the expansion of functional genomic (FG) datasets, which now include hundreds of thousands of tracks across various cell and tissue types, it is critical to establish scalable algorithms integrating thousands of diverse FG annotations with GWAS results. RESULTS: We propose BTS (Bayesian Tissue Score), a novel, highly efficient algorithm uniquely designed for (i) identifying affected cell types and functional elements (context-mapping) and (ii) fine-mapping potentially causal variants in a context-specific manner using large collections of cell type-specific FG annotation tracks. BTS leverages GWAS summary statistics and annotation-specific Bayesian models to analyze genome-wide annotation tracks, including enhancers, open chromatin, and histone marks. We evaluated BTS on GWAS summary statistics for immune and cardiovascular traits, such as Inflammatory Bowel Disease (IBD), Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (SLE), and Coronary Artery Disease (CAD). Our results demonstrate that BTS is over 100× more efficient in estimating functional annotation effects and context-specific variant fine-mapping compared to existing methods. Importantly, this large-scale Bayesian approach prioritizes both known and novel annotations, cell types, genomic regions, and variants and provides valuable biological insights into the functional contexts of these diseases. AVAILABILITY AND IMPLEMENTATION: Docker image is available at https://hub.docker.com/r/wanglab/bts with preinstalled BTS R package (https://bitbucket.org/wanglab-upenn/BTS-R) and BTS GWAS summary statistics analysis pipeline (https://bitbucket.org/wanglab-upenn/bts-pipeline).

Genome-Wide Association Study↗

ChromCall: assigning chromatin status to defined genomic regions using epigenomic profiling data.

MOTIVATION: Chromatin regulation is crucial for modulating gene expression and cellular function by altering DNA accessibility. Defining and understanding chromatin regulation across diverse biological conditions, including health and disease, requires quantification of both the presence and enrichment level of diverse DNA-binding factors and chromatin modifications across defined genomic regions. Existing approaches mainly rely on peak-based or genome-wide models, which identify high-signal regions but do not annotate chromatin status at predefined functional genomic regions, such as promoters or enhancers. This lack of region-based annotation limits downstream comparative and integrative analyses across multiple factors and datasets, prompting us to create ChromCall. RESULTS: ChromCall is an R package for region-based chromatin enrichment analysis that provides a robust and extensible foundation for transparent and reproducible epigenomic profiling at predefined genomic regions. We applied ChromCall to ChIP-seq data from glioblastoma (GBM) brain tumours and found that the promoters of genes implicated in treatment resistance are significantly more likely to exhibit a combination of histone marks associated with phenotypic plasticity. This highlights a potential novel mechanism of therapeutic escape in these deadly tumours. AVAILABILITY AND IMPLEMENTATION: The R package is available on https://github.com/GliomaGenomics/ChromCall and the version used in this paper is archived at https://doi.org/10.5281/zenodo.19580967.

Chromatin↗