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Epigenomic signatures on paralogous genes reveal underappreciated universality of active histone codes adopted across animals. Comput Struct Biotechnol J 2022; 20:353-367. [PMID: 35035788 PMCID: PMC8741409 DOI: 10.1016/j.csbj.2021.12.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/15/2021] [Accepted: 12/18/2021] [Indexed: 11/21/2022] Open
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Yukawa M, Jagannathan S, Vallabh S, Kartashov AV, Chen X, Weirauch MT, Barski A. AP-1 activity induced by co-stimulation is required for chromatin opening during T cell activation. J Exp Med 2020; 217:jem.20182009. [PMID: 31653690 PMCID: PMC7037242 DOI: 10.1084/jem.20182009] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 02/06/2019] [Accepted: 09/23/2019] [Indexed: 12/24/2022] Open
Abstract
Activation of T cells is dependent on the organized and timely opening and closing of chromatin. Herein, we identify AP-1 as the transcription factor that directs most of this remodeling. Chromatin accessibility profiling showed quick opening of closed chromatin in naive T cells within 5 h of activation. These newly opened regions were strongly enriched for the AP-1 motif, and indeed, ChIP-seq demonstrated AP-1 binding at >70% of them. Broad inhibition of AP-1 activity prevented chromatin opening at AP-1 sites and reduced the expression of nearby genes. Similarly, induction of anergy in the absence of co-stimulation during activation was associated with reduced induction of AP-1 and a failure of proper chromatin remodeling. The translational relevance of these findings was highlighted by the substantial overlap of AP-1-dependent elements with risk loci for multiple immune diseases, including multiple sclerosis, inflammatory bowel disease, and allergic disease. Our findings define AP-1 as the key link between T cell activation and chromatin remodeling.
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Affiliation(s)
- Masashi Yukawa
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Sajjeev Jagannathan
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Sushmitha Vallabh
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Andrey V Kartashov
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Xiaoting Chen
- Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Matthew T Weirauch
- Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH.,Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Artem Barski
- Division of Allergy & Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH.,Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
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Rizwani W, Schaal C, Kunigal S, Coppola D, Chellappan S. Mammalian lysine histone demethylase KDM2A regulates E2F1-mediated gene transcription in breast cancer cells. PLoS One 2014; 9:e100888. [PMID: 25029110 PMCID: PMC4100745 DOI: 10.1371/journal.pone.0100888] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 05/30/2014] [Indexed: 01/01/2023] Open
Abstract
It is established that histone modifications like acetylation, methylation, phosphorylation and ubiquitination affect chromatin structure and modulate gene expression. Lysine methylation/demethylation on Histone H3 and H4 is known to affect transcription and is mediated by histone methyl transferases and histone demethylases. KDM2A/JHDM1A/FBXL11 is a JmjC-containing histone demethylase that targets mono- and dimethylated Lys36 residues of Histone H3; its function in breast cancer is not fully understood. Here we show that KDM2A is strongly expressed in myoepithelial cells (MEPC) in breast cancer tissues by immunohistochemistry. Ductal cells from ductal carcinoma in situ (DCIS) and infiltrating ductal carcinoma (IDC) show positive staining for KDM2A, the expression decreases with disease progression to metastasis. Since breast MEPCs have tumor-suppressive and anti-angiogenic properties, we hypothesized that KDM2A could be contributing to some of these functions. Silencing KDM2A with small interfering RNAs demonstrated increased invasion and migration of breast cancer cells by suppressing a subset of matrix metalloproteinases (MMP-2, -9, -14 and -15), as seen by real-time PCR. HUVEC cells showed increased angiogenic tubule formation ability in the absence of KDM2A, with a concomitant increase in the expression of VEGF receptors, FLT-1 and KDR. KDM2A physically bound to both Rb and E2F1 in a cell cycle dependent manner and repressed E2F1 transcriptional activity. Chromatin immunoprecipitation (ChIP) assays revealed that KDM2A associates with E2F1-regulated proliferative promoters CDC25A and TS in early G-phase and dissociates in S-phase. Further, KDM2A could also be detected on MMP9, 14 and 15 promoters, as well as promoters of FLT1 and KDR. KDM2A could suppress E2F1-mediated induction of these promoters in transient transfection experiments. These results suggest a regulatory role for KDM2A in breast cancer cell invasion and migration, through the regulation of E2F1 function.
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Affiliation(s)
- Wasia Rizwani
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Courtney Schaal
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Sateesh Kunigal
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Domenico Coppola
- Department of Anatomic Pathology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Srikumar Chellappan
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
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4
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Abstract
Gene activity is regulated by transcriptional and epigenetic mechanisms. A paper in 2005 by Zhang et al.1 showed that STAT3 binds to the DNA methyl transferase, DNMT1 and their data indicated that STAT3 may cause epigenetic gene silencing by targeting DNMT1 to the PTPN6 promoter. Now, a paper by Lee et al.2 has fleshed out the mechanism. They provide evidence that acetylation of STAT3 regulates the binding of DNMT1, CpG DNA methylation and regulation of several genes, including that encoding the estrogen receptor α (ESR1) in breast cancer cells.
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Affiliation(s)
- N Shaun B Thomas
- Department of Haematological Medicine; Rayne Institute; King's College London; London, UK
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5
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Lim PS, Li J, Holloway AF, Rao S. Epigenetic regulation of inducible gene expression in the immune system. Immunology 2013; 139:285-93. [PMID: 23521628 DOI: 10.1111/imm.12100] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 03/07/2013] [Accepted: 03/13/2013] [Indexed: 01/12/2023] Open
Abstract
T cells are exquisitely poised to respond rapidly to pathogens and have proved an instructive model for exploring the regulation of inducible genes. Individual genes respond to antigenic stimulation in different ways, and it has become clear that the interplay between transcription factors and the chromatin platform of individual genes governs these responses. Our understanding of the complexity of the chromatin platform and the epigenetic mechanisms that contribute to transcriptional control has expanded dramatically in recent years. These mechanisms include the presence/absence of histone modification marks, which form an epigenetic signature to mark active or inactive genes. These signatures are dynamically added or removed by epigenetic enzymes, comprising an array of histone-modifying enzymes, including the more recently recognized chromatin-associated signalling kinases. In addition, chromatin-remodelling complexes physically alter the chromatin structure to regulate chromatin accessibility to transcriptional regulatory factors. The advent of genome-wide technologies has enabled characterization of the chromatin landscape of T cells in terms of histone occupancy, histone modification patterns and transcription factor association with specific genomic regulatory regions, generating a picture of the T-cell epigenome. Here, we discuss the multi-layered regulation of inducible gene expression in the immune system, focusing on the interplay between transcription factors, and the T-cell epigenome, including the role played by chromatin remodellers and epigenetic enzymes. We will also use IL2, a key inducible cytokine gene in T cells, as an example of how the different layers of epigenetic mechanisms regulate immune responsive genes during T-cell activation.
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Affiliation(s)
- Pek Siew Lim
- Discipline of Biomedical Sciences, Faculty of Education, Science, Technology and Mathematics, University of Canberra, Canberra, Australia.
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6
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Black JC, Van Rechem C, Whetstine JR. Histone lysine methylation dynamics: establishment, regulation, and biological impact. Mol Cell 2013. [PMID: 23200123 DOI: 10.1016/j.molcel.2012.11.006] [Citation(s) in RCA: 844] [Impact Index Per Article: 76.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Histone lysine methylation has emerged as a critical player in the regulation of gene expression, cell cycle, genome stability, and nuclear architecture. Over the past decade, a tremendous amount of progress has led to the characterization of methyl modifications and the lysine methyltransferases (KMTs) and lysine demethylases (KDMs) that regulate them. Here, we review the discovery and characterization of the KMTs and KDMs and the methyl modifications they regulate. We discuss the localization of the KMTs and KDMs as well as the distribution of lysine methylation throughout the genome. We highlight how these data have shaped our view of lysine methylation as a key determinant of complex chromatin states. Finally, we discuss the regulation of KMTs and KDMs by proteasomal degradation, posttranscriptional mechanisms, and metabolic status. We propose key questions for the field and highlight areas that we predict will yield exciting discoveries in the years to come.
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Affiliation(s)
- Joshua C Black
- Massachusetts General Hospital Cancer Center and Department of Medicine, Harvard Medical School, 13(th) Street, Charlestown, MA 02129, USA
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7
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MicroRNA-mediated restriction of HIV-1 in resting CD4+ T cells and monocytes. Viruses 2012; 4:1390-409. [PMID: 23170164 PMCID: PMC3499811 DOI: 10.3390/v4091390] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/28/2012] [Accepted: 07/30/2012] [Indexed: 02/06/2023] Open
Abstract
In contrast to activated CD4+ T cells and differentiated macrophages, resting CD4+ T cells and monocytes are non-permissive for HIV-1 replication. The mediators which regulate the resting or quiescent phenotype are often actively involved in the restriction of viral replication and the establishment and maintenance of viral latency. Recently, certain microRNAs which are highly expressed in resting cells have been implicated in this capacity, inhibiting the expression of cellular proteins that are also viral co-factors; following activation these microRNAs exhibit decreased expression, while their targets are correspondingly up-regulated, contributing to a favorable milieu for virus replication. Other microRNAs exhibiting a similar expression pattern in resting and activated cells have been shown to directly target the HIV-1 genome. In this review we will discuss the resting state and the causes behind viral restriction in resting cells, with emphasis on the role of microRNAs.
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Srivastava S, Mishra RK, Dhawan J. Regulation of cellular chromatin state: insights from quiescence and differentiation. Organogenesis 2012; 6:37-47. [PMID: 20592864 DOI: 10.4161/org.6.1.11337] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2009] [Revised: 01/19/2010] [Accepted: 01/29/2010] [Indexed: 11/19/2022] Open
Abstract
The identity and functionality of eukaryotic cells is defined not just by their genomic sequence which remains constant between cell types, but by their gene expression profiles governed by epigenetic mechanisms. Epigenetic controls maintain and change the chromatin state throughout development, as exemplified by the setting up of cellular memory for the regulation and maintenance of homeotic genes in proliferating progenitors during embryonic development. Higher order chromatin structure in reversibly arrested adult stem cells also involves epigenetic regulation and in this review we highlight common trends governing chromatin states, focusing on quiescence and differentiation during myogenesis. Together, these diverse developmental modules reveal the dynamic nature of chromatin regulation providing fresh insights into the role of epigenetic mechanisms in potentiating development and differentiation.
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Affiliation(s)
- Surabhi Srivastava
- Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Hyderabad, India.
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Abstract
The haploid human genome contains approximately 29 million CpGs that exist in a methylated, hydroxymethylated or unmethylated state, collectively referred to as the DNA methylome. The methylation status of cytosines in CpGs and occasionally in non-CpG cytosines influences protein–DNA interactions, gene expression, and chromatin structure and stability. The degree of DNA methylation at particular loci may be heritable transgenerationally and may be altered by environmental exposures and diet, potentially contributing to the development of human diseases. For the vast majority of normal and disease methylomes however, less than 1% of the CpGs have been assessed, revealing the formative stage of methylation mapping techniques. Thus, there is significant discovery potential in new genome-scale platforms applied to methylome mapping, particularly oligonucleotide arrays and the transformative technology of next-generation sequencing. Here, we outline the currently used methylation detection reagents and their application to microarray and sequencing platforms. A comparison of the emerging methods is presented, highlighting their degrees of technical complexity, methylome coverage and precision in resolving methylation. Because there are hundreds of unique methylomes to map within one individual and interindividual variation is likely to be significant, international coordination is essential to standardize methylome platforms and to create a full repository of methylome maps from tissues and unique cell types.
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Affiliation(s)
- Shaun D Fouse
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, CA 94158, USA.
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Lim PS, Shannon MF, Hardy K. Epigenetic control of inducible gene expression in the immune system. Epigenomics 2012; 2:775-95. [PMID: 22122082 DOI: 10.2217/epi.10.55] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
It has been well documented that active genes, and their promoters and enhancers have a different chromatin or epigenomic environment compared with unexpressed genes. In addition, the epigenome may influence not only which genes are expressed, but also which genes can be induced in response to activation or differentiation signals. Immune cells respond to activation signals by rapidly inducing the expression of specific gene sets, and therefore this is a good system in which to examine the role of the epigenome in gene activation and cell differentiation. Several studies have now found that many immediate-early inducible genes exist in a similar epigenomic environment to active genes even in the unstimulated state. Some studies suggest that subsets of these genes may even have RNA polymerase II at their promoters and induction may be controlled downstream of its recruitment. Other inducible genes, however, undergo changes to histone modifications, levels or variant composition upon activation. In this article, we discuss how the epigenome of immune cells regulates inducible gene expression and discuss the differences between the immediate responses to activation signals and the longer term changes observed during differentiation.
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Affiliation(s)
- Pek Siew Lim
- Department of Genome Biology, John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
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Nozaki T, Yachie N, Ogawa R, Kratz A, Saito R, Tomita M. Tight associations between transcription promoter type and epigenetic variation in histone positioning and modification. BMC Genomics 2011; 12:416. [PMID: 21846408 PMCID: PMC3170308 DOI: 10.1186/1471-2164-12-416] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 08/17/2011] [Indexed: 11/19/2022] Open
Abstract
Background Transcription promoters are fundamental genomic cis-elements controlling gene expression. They can be classified into two types by the degree of imprecision of their transcription start sites: peak promoters, which initiate transcription from a narrow genomic region; and broad promoters, which initiate transcription from a wide-ranging region. Eukaryotic transcription initiation is suggested to be associated with the genomic positions and modifications of nucleosomes. For instance, it has been recently shown that histone with H3K9 acetylation (H3K9ac) is more likely to be distributed around broad promoters rather than peak promoters; it can thus be inferred that there is an association between histone H3K9 and promoter architecture. Results Here, we performed a systematic analysis of transcription promoters and gene expression, as well as of epigenetic histone behaviors, including genomic position, stability within the chromatin, and several modifications. We found that, in humans, broad promoters, but not peak promoters, generally had significant associations with nucleosome positioning and modification. Specifically, around broad promoters histones were highly distributed and aligned in an orderly fashion. This feature was more evident with histones that were methylated or acetylated; moreover, the nucleosome positions around the broad promoters were more stable than those around the peak ones. More strikingly, the overall expression levels of genes associated with broad promoters (but not peak promoters) with modified histones were significantly higher than the levels of genes associated with broad promoters with unmodified histones. Conclusion These results shed light on how epigenetic regulatory networks of histone modifications are associated with promoter architecture.
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Affiliation(s)
- Tadasu Nozaki
- Institute for Advanced Biosciences, Keio University, Tsuruoka, 997-0017, Japan
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Abstract
Human tumors often contain slowly proliferating cancer cells that resist treatment, but we do not know precisely how these cells arise. We show that rapidly proliferating cancer cells can divide asymmetrically to produce slowly proliferating "G0-like" progeny that are enriched following chemotherapy in breast cancer patients. Asymmetric cancer cell division results from asymmetric suppression of AKT/PKB kinase signaling in one daughter cell during telophase of mitosis. Moreover, inhibition of AKT signaling with small-molecule drugs can induce asymmetric cancer cell division and the production of slow proliferators. Cancer cells therefore appear to continuously flux between symmetric and asymmetric division depending on the precise state of their AKT signaling network. This model may have significant implications for understanding how tumors grow, evade treatment, and recur.
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Reducing MCM levels in human primary T cells during the G(0)-->G(1) transition causes genomic instability during the first cell cycle. Oncogene 2010; 29:3803-14. [PMID: 20440261 DOI: 10.1038/onc.2010.138] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
DNA replication is tightly regulated, but paradoxically there is reported to be an excess of MCM DNA replication proteins over the number of replication origins. Here, we show that MCM levels in primary human T cells are induced during the G(0)-->G(1) transition and are not in excess in proliferating cells. The level of induction is critical as we show that a 50% reduction leads to increased centromere separation, premature chromatid separation (PCS) and gross chromosomal abnormalities typical of genomic instability syndromes. We investigated the mechanisms involved and show that a reduction in MCM levels causes dose-dependent DNA damage involving activation of ATR & ATM and Chk1 & Chk2. There is increased DNA mis-repair by non-homologous end joining (NHEJ) and both NHEJ and homologous recombination are necessary for Mcm7-depleted cells to progress to metaphase. Therefore, a simple reduction in MCM loading onto DNA, which occurs in cancers as a result of aberrant cell cycle control, is sufficient to cause PCS and gross genomic instability within one cell cycle.
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Kratz A, Arner E, Saito R, Kubosaki A, Kawai J, Suzuki H, Carninci P, Arakawa T, Tomita M, Hayashizaki Y, Daub CO. Core promoter structure and genomic context reflect histone 3 lysine 9 acetylation patterns. BMC Genomics 2010; 11:257. [PMID: 20409305 PMCID: PMC2867832 DOI: 10.1186/1471-2164-11-257] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 04/21/2010] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Histone modifications play an important role in gene regulation. Acetylation of histone 3 lysine 9 (H3K9ac) is generally associated with transcription initiation and unfolded chromatin, thereby positively influencing gene expression. Deep sequencing of the 5' ends of gene transcripts using DeepCAGE delivers detailed information about the architecture and expression level of gene promoters. The combination of H3K9ac ChIP-chip and DeepCAGE in a myeloid leukemia cell line (THP-1) allowed us to study the spatial distribution of H3K9ac around promoters using a novel clustering approach. The promoter classes were analyzed for association with relevant genomic sequence features. RESULTS We performed a clustering of 4,481 promoters according to their surrounding H3K9ac signal and analyzed the clustered promoters for association with different sequence features. The clustering revealed three groups with major H3K9ac signal upstream, centered and downstream of the promoter. Narrow single peak promoters tend to have a concentrated activity of H3K9ac in the upstream region, while broad promoters tend to have a concentrated activity of H3K9ac and RNA polymerase II binding in the centered and downstream regions. A subset of promoters with high gene expression level, compared to subsets with low and medium gene expression, shows dramatic increase in H3K9ac activity in the upstream cluster only; this may indicate that promoters in the centered and downstream clusters are predominantly regulated at post-initiation steps. Furthermore, the upstream cluster is depleted in CpG islands and more likely to regulate un-annotated genes. CONCLUSIONS Clustering core promoters according to their surrounding acetylation signal is a promising approach for the study of histone modifications. When examining promoters clustered into groups according to their surrounding H3K9 acetylation signal, we find that the relative localization and intensity of H3K9ac is very specific depending on characteristic sequence features of the promoter. Experimental data from DeepCAGE and ChIP-chip experiments using undifferentiated (monocyte) and differentiated (macrophage) THP-1 cells leads us to the same conclusions.
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Affiliation(s)
- Anton Kratz
- Keiko University, Graduate School of Media and Governance, Kanagawa, Japan
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Cuddapah S, Barski A, Zhao K. Epigenomics of T cell activation, differentiation, and memory. Curr Opin Immunol 2010; 22:341-7. [PMID: 20226645 DOI: 10.1016/j.coi.2010.02.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 02/04/2010] [Accepted: 02/11/2010] [Indexed: 11/15/2022]
Abstract
Activation of T cells is an essential step in the immunological response to infection. Although activation of naïve T cells results in proliferation and slow differentiation into cytokine-producing effector cells, antigen engagement with memory cells leads to cytokine production immediately. Even though the cell surface signaling events are similar in both the cases, the outcome is different, suggesting that distinct regulatory mechanisms may exist downstream of the activation signals. Recent advances in the understanding of global epigenetic patterns in T cells have resulted in the appreciation of the role of epigenetic mechanisms in processes such as activation and differentiation. In this review we discuss recent data suggesting that naïve T cell activation, differentiation, and lineage commitment result in epigenetic changes and a fine balance between different histone modifications is required. On the other hand, memory T cells are poised and do not require epigenetic changes for short-term activation.
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Affiliation(s)
- Suresh Cuddapah
- Laboratory of Molecular Immunology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Laird PW. Principles and challenges of genome-wide DNA methylation analysis. Nat Rev Genet 2010; 11:191-203. [DOI: 10.1038/nrg2732] [Citation(s) in RCA: 1067] [Impact Index Per Article: 76.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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