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Patty BJ, Hainer SJ. Widespread impact of nucleosome remodelers on transcription at cis-regulatory elements. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.12.589208. [PMID: 38659863 PMCID: PMC11042195 DOI: 10.1101/2024.04.12.589208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Nucleosome remodeling complexes and other regulatory factors work in concert to build a chromatin environment that directs the expression of a distinct set of genes in each cell using cis-regulatory elements (CREs), such as promoters and enhancers, that drive transcription of both mRNAs and CRE-associated non-coding RNAs (ncRNAs). Two classes of CRE-associated ncRNAs include upstream antisense RNAs (uaRNAs), which are transcribed divergently from a shared mRNA promoter, and enhancer RNAs (eRNAs), which are transcribed bidirectionally from active enhancers. The complicated network of CRE regulation by nucleosome remodelers remains only partially explored, with a focus on a select, limited number of remodelers. We endeavored to elucidate a remodeler-based regulatory network governing CRE-associated transcription (mRNA, eRNA, and uaRNA) in murine embryonic stem (ES) cells to test the hypothesis that many SNF2-family nucleosome remodelers collaborate to regulate the coding and non-coding transcriptome via alteration of underlying nucleosome architecture. Using depletion followed by transient transcriptome sequencing (TT-seq), we identified thousands of misregulated mRNAs and CRE-associated ncRNAs across the remodelers examined, identifying novel contributions by understudied remodelers in the regulation of coding and noncoding transcription. Our findings suggest that mRNA and eRNA transcription are coordinately co-regulated, while mRNA and uaRNAs sharing a common promoter are independently regulated. Subsequent mechanistic studies suggest that while remodelers SRCAP and CHD8 modulate transcription through classical mechanisms such as transcription factors and histone variants, a broad set of remodelers including SMARCAL1 indirectly contribute to transcriptional regulation through maintenance of genomic stability and proper Integrator complex localization. This study systematically examines the contribution of SNF2-remodelers to the CRE-associated transcriptome, identifying at least two classes for remodeler action.
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Affiliation(s)
- Benjamin J. Patty
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA USA
| | - Sarah J. Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA USA
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA USA
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2
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García A, Durán L, Sánchez M, González S, Santamaría R, Antequera F. Asymmetrical nucleosomal DNA signatures regulate transcriptional directionality. Cell Rep 2024; 43:113605. [PMID: 38127622 DOI: 10.1016/j.celrep.2023.113605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 10/03/2023] [Accepted: 12/05/2023] [Indexed: 12/23/2023] Open
Abstract
Despite the symmetrical structure of nucleosomes, in vitro studies have shown that transcription proceeds with different efficiency depending on the orientation of the DNA sequence around them. However, it is unclear whether this functional asymmetry is present in vivo and whether it could regulate transcriptional directionality. Here, we report that the proximal and distal halves of nucleosomal DNA contribute differentially to nucleosome stability in the genome. In +1 nucleosomes, this asymmetry facilitates or hinders transcription depending on the orientation of its underlying DNA, and this difference is associated with an asymmetrical interaction between DNA and histones. These properties are encoded in the DNA signature of +1 nucleosomes, since its incorporation in the two orientations into downstream nucleosomes renders them asymmetrically accessible to MNase and inverts the balance between sense and antisense transcription. Altogether, our results show that nucleosomal DNA endows nucleosomes with asymmetrical properties that modulate the directionality of transcription.
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Affiliation(s)
- Alicia García
- Instituto de Biología Funcional y Genómica (IBFG), CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Laura Durán
- Instituto de Biología Funcional y Genómica (IBFG), CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Mar Sánchez
- Instituto de Biología Funcional y Genómica (IBFG), CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Sara González
- Instituto de Biología Funcional y Genómica (IBFG), CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
| | - Rodrigo Santamaría
- Departamento de Informática y Automática, Universidad de Salamanca/Facultad de Ciencias, Plaza de los Caídos s/n, 37007 Salamanca, Spain
| | - Francisco Antequera
- Instituto de Biología Funcional y Genómica (IBFG), CSIC-Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain.
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3
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Martin BJE, Ablondi EF, Goglia C, Mimoso CA, Espinel-Cabrera PR, Adelman K. Global identification of SWI/SNF targets reveals compensation by EP400. Cell 2023; 186:5290-5307.e26. [PMID: 37922899 PMCID: PMC11307202 DOI: 10.1016/j.cell.2023.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 08/11/2023] [Accepted: 10/03/2023] [Indexed: 11/07/2023]
Abstract
Mammalian SWI/SNF chromatin remodeling complexes move and evict nucleosomes at gene promoters and enhancers to modulate DNA access. Although SWI/SNF subunits are commonly mutated in disease, therapeutic options are limited by our inability to predict SWI/SNF gene targets and conflicting studies on functional significance. Here, we leverage a fast-acting inhibitor of SWI/SNF remodeling to elucidate direct targets and effects of SWI/SNF. Blocking SWI/SNF activity causes a rapid and global loss of chromatin accessibility and transcription. Whereas repression persists at most enhancers, we uncover a compensatory role for the EP400/TIP60 remodeler, which reestablishes accessibility at most promoters during prolonged loss of SWI/SNF. Indeed, we observe synthetic lethality between EP400 and SWI/SNF in cancer cell lines and human cancer patient data. Our data define a set of molecular genomic features that accurately predict gene sensitivity to SWI/SNF inhibition in diverse cancer cell lines, thereby improving the therapeutic potential of SWI/SNF inhibitors.
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Affiliation(s)
- Benjamin J E Martin
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Ludwig Center at Harvard, Boston, MA 02115, USA
| | - Eileen F Ablondi
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Christine Goglia
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Claudia A Mimoso
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Piero R Espinel-Cabrera
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Karen Adelman
- Department of Biological Chemistry and Molecular Pharmacology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Ludwig Center at Harvard, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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4
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Klein DC, Lardo SM, McCannell KN, Hainer SJ. FACT regulates pluripotency through proximal and distal regulation of gene expression in murine embryonic stem cells. BMC Biol 2023; 21:167. [PMID: 37542287 PMCID: PMC10403911 DOI: 10.1186/s12915-023-01669-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 07/26/2023] [Indexed: 08/06/2023] Open
Abstract
BACKGROUND The FACT complex is a conserved histone chaperone with critical roles in transcription and histone deposition. FACT is essential in pluripotent and cancer cells, but otherwise dispensable for most mammalian cell types. FACT deletion or inhibition can block induction of pluripotent stem cells, yet the mechanism through which FACT regulates cell fate decisions remains unclear. RESULTS To explore the mechanism for FACT function, we generated AID-tagged murine embryonic cell lines for FACT subunit SPT16 and paired depletion with nascent transcription and chromatin accessibility analyses. We also analyzed SPT16 occupancy using CUT&RUN and found that SPT16 localizes to both promoter and enhancer elements, with a strong overlap in binding with OCT4, SOX2, and NANOG. Over a timecourse of SPT16 depletion, nucleosomes invade new loci, including promoters, regions bound by SPT16, OCT4, SOX2, and NANOG, and TSS-distal DNaseI hypersensitive sites. Simultaneously, transcription of Pou5f1 (encoding OCT4), Sox2, Nanog, and enhancer RNAs produced from these genes' associated enhancers are downregulated. CONCLUSIONS We propose that FACT maintains cellular pluripotency through a precise nucleosome-based regulatory mechanism for appropriate expression of both coding and non-coding transcripts associated with pluripotency.
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Affiliation(s)
- David C Klein
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Santana M Lardo
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Kurtis N McCannell
- Department of Biology and Epigenetics Institute, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Sarah J Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA.
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5
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Bure IV, Nemtsova MV. Mutual Regulation of ncRNAs and Chromatin Remodeling Complexes in Normal and Pathological Conditions. Int J Mol Sci 2023; 24:ijms24097848. [PMID: 37175555 PMCID: PMC10178202 DOI: 10.3390/ijms24097848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Chromatin remodeling is the one of the main epigenetic mechanisms of gene expression regulation both in normal cells and in pathological conditions. In recent years, a growing number of investigations have confirmed that epigenetic regulators are tightly connected and form a comprehensive network of regulatory pathways and feedback loops. Genes encoding protein subunits of chromatin remodeling complexes are often mutated and change their expression in diseases, as well as non-coding RNAs (ncRNAs). Moreover, different mechanisms of their mutual regulation have already been described. Further understanding of these processes may help apply their clinical potential for establishment of the diagnosis, prognosis, and treatment of the diseases. The therapeutic targeting of the chromatin structure has many limitations because of the complexity of its regulation, with the involvement of a large number of genes, proteins, non-coding transcripts, and other intermediary molecules. However, several successful strategies have been proposed to target subunits of chromatin remodeling complexes and genes encoding them, as well as the ncRNAs that regulate the operation of these complexes and direct them to the target gene regions. In our review, we focus on chromatin remodeling complexes and ncRNAs, their mutual regulation, role in cellular processes and potential clinical application.
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Affiliation(s)
- Irina V Bure
- Laboratory of Medical Genetics, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Marina V Nemtsova
- Laboratory of Medical Genetics, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
- Laboratory of Epigenetics, Research Centre for Medical Genetics, 115522 Moscow, Russia
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6
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Klein DC, Troy K, Tripplehorn SA, Hainer SJ. The esBAF and ISWI nucleosome remodeling complexes influence occupancy of overlapping dinucleosomes and fragile nucleosomes in murine embryonic stem cells. BMC Genomics 2023; 24:201. [PMID: 37055726 PMCID: PMC10103515 DOI: 10.1186/s12864-023-09287-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 03/30/2023] [Indexed: 04/15/2023] Open
Abstract
BACKGROUND Nucleosome remodeling factors regulate the occupancy and positioning of nucleosomes genome-wide through ATP-driven DNA translocation. While many nucleosomes are consistently well-positioned, some nucleosomes and alternative nucleosome structures are more sensitive to nuclease digestion or are transitory. Fragile nucleosomes are nucleosome structures that are sensitive to nuclease digestion and may be composed of either six or eight histone proteins, making these either hexasomes or octasomes. Overlapping dinucleosomes are composed of two merged nucleosomes, lacking one H2A:H2B dimer, creating a 14-mer wrapped by ~ 250 bp of DNA. In vitro studies of nucleosome remodeling suggest that the collision of adjacent nucleosomes by sliding stimulates formation of overlapping dinucleosomes. RESULTS To better understand how nucleosome remodeling factors regulate alternative nucleosome structures, we depleted murine embryonic stem cells of the transcripts encoding remodeler ATPases BRG1 or SNF2H, then performed MNase-seq. We used high- and low-MNase digestion to assess the effects of nucleosome remodeling factors on nuclease-sensitive or "fragile" nucleosome occupancy. In parallel we gel-extracted MNase-digested fragments to enrich for overlapping dinucleosomes. We recapitulate prior identification of fragile nucleosomes and overlapping dinucleosomes near transcription start sites, and identify enrichment of these features around gene-distal DNaseI hypersensitive sites, CTCF binding sites, and pluripotency factor binding sites. We find that BRG1 stimulates occupancy of fragile nucleosomes but restricts occupancy of overlapping dinucleosomes. CONCLUSIONS Overlapping dinucleosomes and fragile nucleosomes are prevalent within the ES cell genome, occurring at hotspots of gene regulation beyond their characterized existence at promoters. Although neither structure is fully dependent on either nucleosome remodeling factor, both fragile nucleosomes and overlapping dinucleosomes are affected by knockdown of BRG1, suggesting a role for the complex in creating or removing these structures.
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Affiliation(s)
- David C Klein
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Kris Troy
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of Quantitative and Systems Biology, University of California, 95343, Merced, Merced, CA, USA
| | - Sarah A Tripplehorn
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Sarah J Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
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7
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RBM10 regulates alternative splicing of lncRNA Neat1 to inhibit the invasion and metastasis of NSCLC. Cancer Cell Int 2022; 22:338. [PMCID: PMC9636673 DOI: 10.1186/s12935-022-02758-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022] Open
Abstract
Abstract
Background
Non-small cell lung cancer (NSCLC) accounts for more than 85% of the total cases with lung cancer. NSCLC is characterized by easy metastasis, which often spreads to bones, brains and livers. RNA-binding motif protein 10 (RBM10) is an alternative splicing (AS) regulator frequently mutated in NSCLC. We found that there were multiple peak binding sites between RBM10 and long non-coding RNA nuclear enriched abundant transcript 1 (LncRNA Neat1) by crosslinking-immunprecipitation and high-throughput sequencing (Clip-Seq). LncRNA Neat1 plays an indispensable role in promoting cancer in a variety of tumors and produces two splicing variants: Neat1_1 and Neat1_2. This study aims to explore the mechanism of RBM10 and LncRNA Neat1 in invasion and metastasis of NSCLC.
Methods
Through histological and cytological experiments, we assessed the expression level of RBM10 protein expression. The interaction between RBM10 and Neat1 was evaluated via Clip-Seq and RNA immunoprecipitation assay. The effect of RBM10 on Neat1 and its splicing variants was identified by RT-qPCR. The effect of RBM10 and Neat1 on invasive and metastasis phenotypes of NSCLC was analyzed using transwell invasion assay and scratch test. Additionally, downstream signaling pathway of RBM10 were identified by immunofluorescence and western blot.
Results
RBM10 exhibited low levels of expression in NSCLC tissues and cells. RBM10 inhibited the invasion and metastasis of NSCLC and recruited Neat1 and Neat1_2. Overexpression of RBM10 simultaneously inhibited Neat1 and Neat1_2, and promoted the expression of Neat1_1. On the other hand, silencing RBM10 promoted Neat1 and Neat1_2, and inhibited the expression of Neat1_1. From this, we concluded that RBM10 regulated AS of Neat1, and the tumor-promoting effect of Neat1 was mainly attributed to Neat1_2. RBM10 had a negative correlation with Neat1_2. In addition, RBM10 upregulated the expression of PTEN and downregulated the phosphorylation of PI3K/AKT/mTOR through Neat1_2, which ultimately inhibited the invasion and metastasis of NSCLC.
Conclusion
The RBM10 regulated AS of Neat1 to cause the imbalance of Neat1_1 and Neat1_2, and RBM10 suppressed the activation of the PTEN/PI3K/AKT/mTOR signal by downregulating Neat1_2, finally affected the invasion and metastasis of NSCLC.
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8
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Wu AC, Vivori C, Patel H, Sideri T, Moretto F, van Werven FJ. RSC and GRFs confer promoter directionality by restricting divergent noncoding transcription. Life Sci Alliance 2022; 5:e202201394. [PMID: 36114005 PMCID: PMC9481977 DOI: 10.26508/lsa.202201394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 09/02/2022] [Accepted: 09/02/2022] [Indexed: 11/24/2022] Open
Abstract
The directionality of gene promoters-the ratio of protein-coding over divergent noncoding transcription-is highly variable. How promoter directionality is controlled remains poorly understood. Here, we show that the chromatin remodelling complex RSC and general regulatory factors (GRFs) dictate promoter directionality by attenuating divergent transcription relative to protein-coding transcription. At gene promoters that are highly directional, depletion of RSC leads to a relative increase in divergent noncoding transcription and thus to a decrease in promoter directionality. We find that RSC has a modest effect on nucleosome positioning upstream in promoters at the sites of divergent transcription. These promoters are also enriched for the binding of GRFs such as Reb1 and Abf1. Ectopic targeting of divergent transcription initiation sites with GRFs or the dCas9 DNA-binding protein suppresses divergent transcription. Our data suggest that RSC and GRFs play a pervasive role in limiting divergent transcription relative to coding direction transcription. We propose that any DNA-binding factor, when stably associated with cryptic transcription start sites, forms a barrier which represses divergent transcription, thereby promoting promoter directionality.
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Affiliation(s)
- Andrew Ck Wu
- Cell Fate and Gene Regulation Laboratory, The Francis Crick Institute, London, UK
| | - Claudia Vivori
- Cell Fate and Gene Regulation Laboratory, The Francis Crick Institute, London, UK
| | - Harshil Patel
- Bioinformatics and Biostatistics, The Francis Crick Institute, London, UK
| | - Theodora Sideri
- Cell Fate and Gene Regulation Laboratory, The Francis Crick Institute, London, UK
| | - Fabien Moretto
- Cell Fate and Gene Regulation Laboratory, The Francis Crick Institute, London, UK
- Institute of Molecular Biology and Biotechnology (IMBB), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Greece
| | - Folkert J van Werven
- Cell Fate and Gene Regulation Laboratory, The Francis Crick Institute, London, UK
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9
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Hemogen /BRG1 cooperativity modulates promoter and enhancer activation during erythropoiesis. Blood 2022; 139:3532-3545. [PMID: 35297980 DOI: 10.1182/blood.2021014308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 03/15/2022] [Indexed: 11/20/2022] Open
Abstract
Hemogen, also known as EDAG, is a hematopoietic tissue-specific gene that regulates the proliferation and differentiation of hematopoietic cells. However, the mechanism underlying hemogen function in erythropoiesis is unknown. We found that depletion of hemogen in human CD34+ erythroid progenitor cells and HUDEP2 cells significantly reduced the expression of genes associated with heme and hemoglobin synthesis, supporting a positive role of hemogen in erythroid maturation. In human K562 cells, hemogen antagonized the occupancy of co-repressors NuRD complex and facilitated LDB1 complex-mediated chromatin looping. Hemogen recruited SWI/SNF complex ATPase BRG1 as a co-activator to regulate nucleosome accessibility and H3K27ac enrichment for promoter and enhancer activity. To ask if hemogen/BRG1 cooperativity is conserved in mammalian systems, we generated hemogen KO/KI mice and investigated hemogen/BRG1 function in murine erythropoiesis. Loss of hemogen in E12.5-E16.5 fetal liver cells impeded erythroid differentiation through reducing the production of mature erythroblasts. ChIP-seq in WT and hemogen KO animal revealed BRG1 is largely dependent on hemogen to regulate chromatin accessibility at erythroid gene promoters and enhancers. In summary, hemogen/BRG1 interaction in mammals is essential for fetal erythroid maturation and hemoglobin production through its active role in promoter and enhancer activity and chromatin organization.
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10
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Nojima T, Proudfoot NJ. Mechanisms of lncRNA biogenesis as revealed by nascent transcriptomics. Nat Rev Mol Cell Biol 2022; 23:389-406. [DOI: 10.1038/s41580-021-00447-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2021] [Indexed: 12/14/2022]
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11
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Chen X, Yang H, Liu G, Zhang Y. NUCOME: A comprehensive database of nucleosome organization referenced landscapes in mammalian genomes. BMC Bioinformatics 2021; 22:321. [PMID: 34120586 PMCID: PMC8201709 DOI: 10.1186/s12859-021-04239-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 06/06/2021] [Indexed: 12/02/2022] Open
Abstract
Background Nucleosome organization is involved in many regulatory activities in various organisms. However, studies integrating nucleosome organization in mammalian genomes are very limited mainly due to the lack of comprehensive data quality control (QC) assessment and uneven data quality of public data sets. Results The NUCOME is a database focused on filtering qualified nucleosome organization referenced landscapes covering various cell types in human and mouse based on QC metrics. The filtering strategy guarantees the quality of nucleosome organization referenced landscapes and exempts users from redundant data set selection and processing. The NUCOME database provides standardized, qualified data source and informative nucleosome organization features at a whole-genome scale and on the level of individual loci. Conclusions The NUCOME provides valuable data resources for integrative analyses focus on nucleosome organization. The NUCOME is freely available at http://compbio-zhanglab.org/NUCOME. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04239-9.
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Affiliation(s)
- Xiaolan Chen
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Science and Technology, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Hui Yang
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Science and Technology, Tongji University, 1239 Siping Road, Shanghai, 200092, China
| | - Guifen Liu
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Science and Technology, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
| | - Yong Zhang
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Science and Technology, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
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12
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Weber CM, Hafner A, Kirkland JG, Braun SMG, Stanton BZ, Boettiger AN, Crabtree GR. mSWI/SNF promotes Polycomb repression both directly and through genome-wide redistribution. Nat Struct Mol Biol 2021; 28:501-511. [PMID: 34117481 PMCID: PMC8504423 DOI: 10.1038/s41594-021-00604-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 05/10/2021] [Indexed: 02/05/2023]
Abstract
The mammalian SWI/SNF complex, or BAF complex, has a conserved and direct role in antagonizing Polycomb-mediated repression. Yet, BAF also promotes repression by Polycomb in stem cells and cancer. How BAF both antagonizes and promotes Polycomb-mediated repression remains unknown. Here, we utilize targeted protein degradation to dissect the BAF-Polycomb axis in mouse embryonic stem cells on short timescales. We report that rapid BAF depletion redistributes Polycomb repressive complexes PRC1 and PRC2 from highly occupied domains, like Hox clusters, to weakly occupied sites normally opposed by BAF. Polycomb redistribution from highly repressed domains results in their decompaction, gain of active epigenomic features and transcriptional derepression. Surprisingly, through dose-dependent degradation of PRC1 and PRC2, we identify a conventional role for BAF in Polycomb-mediated repression, in addition to global Polycomb redistribution. These findings provide new mechanistic insight into the highly dynamic state of the Polycomb-Trithorax axis.
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Affiliation(s)
- Christopher M. Weber
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.,Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Antonina Hafner
- Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Jacob G. Kirkland
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.,Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.,Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Simon M. G. Braun
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.,Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.,University of Geneva, Department of Genetic Medicine, Geneva, Switzerland
| | - Benjamin Z. Stanton
- Nationwide Children’s Hospital, Center for Childhood Cancer and Blood Diseases, Columbus, OH, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA.,Department of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, OH, USA
| | | | - Gerald R. Crabtree
- Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.,Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA.,Correspondence and requests for materials should be addressed to G.R.C.
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13
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Cucinotta CE, Dell RH, Braceros KCA, Tsukiyama T. RSC primes the quiescent genome for hypertranscription upon cell-cycle re-entry. eLife 2021; 10:e67033. [PMID: 34042048 PMCID: PMC8186906 DOI: 10.7554/elife.67033] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 05/26/2021] [Indexed: 12/14/2022] Open
Abstract
Quiescence is a reversible G0 state essential for differentiation, regeneration, stem-cell renewal, and immune cell activation. Necessary for long-term survival, quiescent chromatin is compact, hypoacetylated, and transcriptionally inactive. How transcription activates upon cell-cycle re-entry is undefined. Here we report robust, widespread transcription within the first minutes of quiescence exit. During quiescence, the chromatin-remodeling enzyme RSC was already bound to the genes induced upon quiescence exit. RSC depletion caused severe quiescence exit defects: a global decrease in RNA polymerase II (Pol II) loading, Pol II accumulation at transcription start sites, initiation from ectopic upstream loci, and aberrant antisense transcription. These phenomena were due to a combination of highly robust Pol II transcription and severe chromatin defects in the promoter regions and gene bodies. Together, these results uncovered multiple mechanisms by which RSC facilitates initiation and maintenance of large-scale, rapid gene expression despite a globally repressive chromatin state.
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Affiliation(s)
| | - Rachel H Dell
- Basic Sciences Division, Fred Hutchinson Cancer Research CenterSeattleUnited States
| | - Keean CA Braceros
- Basic Sciences Division, Fred Hutchinson Cancer Research CenterSeattleUnited States
| | - Toshio Tsukiyama
- Basic Sciences Division, Fred Hutchinson Cancer Research CenterSeattleUnited States
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14
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Nucleosome Positioning and Spacing: From Mechanism to Function. J Mol Biol 2021; 433:166847. [PMID: 33539878 DOI: 10.1016/j.jmb.2021.166847] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 01/16/2021] [Accepted: 01/22/2021] [Indexed: 02/08/2023]
Abstract
Eukaryotes associate their genomes with histone proteins, forming nucleosome particles. Nucleosomes regulate and protect the genetic information. They often assemble into evenly spaced arrays of nucleosomes. These regular nucleosome arrays cover significant portions of the genome, in particular over genes. The presence of these evenly spaced nucleosome arrays is highly conserved throughout the entire eukaryotic domain. Here, we review the mechanisms behind the establishment of this primary structure of chromatin with special emphasis on the biogenesis of evenly spaced nucleosome arrays. We highlight the roles that transcription, nucleosome remodelers, DNA sequence, and histone density play towards the formation of evenly spaced nucleosome arrays and summarize our current understanding of their cellular functions. We end with key unanswered questions that remain to be explored to obtain an in-depth understanding of the biogenesis and function of the nucleosome landscape.
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15
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Abstract
In the past several decades, the establishment of in vitro models of pluripotency has ushered in a golden era for developmental and stem cell biology. Research in this arena has led to profound insights into the regulatory features that shape early embryonic development. Nevertheless, an integrative theory of the epigenetic principles that govern the pluripotent nucleus remains elusive. Here, we summarize the epigenetic characteristics that define the pluripotent state. We cover what is currently known about the epigenome of pluripotent stem cells and reflect on the use of embryonic stem cells as an experimental system. In addition, we highlight insights from super-resolution microscopy, which have advanced our understanding of the form and function of chromatin, particularly its role in establishing the characteristically "open chromatin" of pluripotent nuclei. Further, we discuss the rapid improvements in 3C-based methods, which have given us a means to investigate the 3D spatial organization of the pluripotent genome. This has aided the adaptation of prior notions of a "pluripotent molecular circuitry" into a more holistic model, where hotspots of co-interacting domains correspond with the accumulation of pluripotency-associated factors. Finally, we relate these earlier hypotheses to an emerging model of phase separation, which posits that a biophysical mechanism may presuppose the formation of a pluripotent-state-defining transcriptional program.
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Affiliation(s)
| | - Eran Meshorer
- Department of Genetics, the Institute of Life Sciences
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel 9190400
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16
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Hou M, Wu N, Yao L. LncRNA CBR3-AS1 potentiates Wnt/β-catenin signaling to regulate lung adenocarcinoma cells proliferation, migration and invasion. Cancer Cell Int 2021; 21:36. [PMID: 33422081 PMCID: PMC7796595 DOI: 10.1186/s12935-020-01685-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 11/27/2020] [Indexed: 12/11/2022] Open
Abstract
Background Long non-coding RNAs (lncRNAs) are pervasively transcribed in genome and emerging as a new player in tumorigenesis due to their functions in transcriptional, posttranscriptional and epigenetic mechanisms of gene regulation. As the most frequent malignancy and the foremost source of cancer mortality, lung cancer is a heterogeneous disorder. The most common type of lung cancer is Non-small cell lung cancer (NSCLC), occupying 85% of the total cases, and the main subtypes of NSCLC include lung adenocarcinoma (LAD), large cell carcinoma (LCC), and lung squamous cell carcinoma (LSCC). Recently, numerous lncRNAs have been reported to be strongly linked to NSCLC. In the present study, we found that a new lncRNA CBR3-AS1 is highly expressed in lung cancer. In addition, we also examined the expression of lncRNA CBR3-AS1 in 60 of LADs, 40 of LCCs and 40 of LSCCs patient samples, finding that CBR3-AS1 was specificity highly expressed in LAD cancer tissues. Mechanically, we discovered that CBR3-AS1 could regulate the proliferation, migration and invasion of LAD cells through targeting Wnt/β-catenin signaling. Methods Real-time PCR, RNA-pulldown, RIP, western blotting, lentivirus transfection, luciferase reporter assays, cell proliferation assays, colony formation assays, wound healing scratch assays and transwell assays were employed to examine the relationship between lncRNA CBR3-AS1 and its regulation of Wnt/β-catenin signaling in LAD cells. Results LncRNA CBR3-AS1 is highly-expressed in LAD and cell lines. LncRNA CBR3-AS1 shows physical association with β-catenin. CBR3-AS1 could facilitate Wnt/β-catenin signaling activation thought promoting nuclear localization of β-catenin. CBR3-AS1 promotes LAD cell proliferation, migration and invasion by targeting Wnt/β-catenin signaling. Conclusion It can be found that a new functional lncRNA CBR3-AS1 could promote nuclear localization of β-catenin so as to facilitate Wnt/β-catenin signaling activation and regulate the proliferation, migration and invasion of LAD cells.
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Affiliation(s)
- Min Hou
- Clinical Laboratory, Tianjin Chest Hospital, No. 261, South Taierzhuang Road, Tianjin, 300222, China.
| | - Nannan Wu
- Clinical Laboratory, Tianjin Chest Hospital, No. 261, South Taierzhuang Road, Tianjin, 300222, China
| | - Lili Yao
- Clinical Laboratory, Tianjin Chest Hospital, No. 261, South Taierzhuang Road, Tianjin, 300222, China
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17
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Liu Q, Dong J, Li J, Duan Y, Wang K, Kong Q, Zhang H. LINC01255 combined with BMI1 to regulate human mesenchymal stromal senescence and acute myeloid leukemia cell proliferation through repressing transcription of MCP-1. Clin Transl Oncol 2021; 23:1105-1116. [PMID: 33405050 DOI: 10.1007/s12094-020-02505-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/05/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND Long non-coding RNAs (lncRNAs) govern fundamental biochemical and cellular biology processes, for example, participate in chromatin remodeling, imprinting, splicing, transcriptional regulation and translation. Dysregulation of lncRNA expression is act as a feature of various diseases and cancers, including hematopoietic malignancies. However, the clinical relevance of myelodysplastic syndrome (MDS) and acute myeloid leukemia preceded by MDS (MDS-AML) requires further research. Recently, lncRNAs have been demonstrated, which play an important role in hematopoiesis, thus, to further finding more functional lncRNA seemed particularly important. METHODS Western blotting, real-time PCR, RNA-pulldown, RIP (RNA immunoprecipitation), Chromatin immunoprecipitation (ChIP), cellular compartments extraction assays, SA-β-gal staining, lentivirus transfection, cell viability assay and cell proliferation assays were used to examine the relationship between lncRNA LINC01255 and its regulation of p53-p21 pathway in human mesenchymal stromal and acute myeloid leukemia cells. RESULTS LncRNA LINC01255 is highly expressed in bone marrow cells of AML patients, CD34+ cells of MDS-AML patients and AML cell lines and the higher expression of LINC01255 is associated with poor survival rate of AML patients. LINC01255 can interact with BMI1 and repress the transcription of MCP-1 to active p53-p21 pathway, thus inhibiting the senescence of human mesenchymal stromal and proliferation of acute myeloid leukemia cell. CONCLUSIONS We discovered a novel functional lncRNA LINC01255, which can regulate the senescence of human mesenchymal stromal and the proliferation of acute myeloid leukemia cell through inhibiting the transcription of MCP-1.
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Affiliation(s)
- Q Liu
- Clinical Laboratory, The Second Affiliated Hospital of Shandong First Medical University, Taian, Shandong, China
| | - J Dong
- Department of Hematology, The Second Affiliated Hospital of Shandong First Medical University, No. 706, Taishan Street, Taian, 271000, Shandong, China
| | - J Li
- Department of Hematology, The Second Affiliated Hospital of Shandong First Medical University, No. 706, Taishan Street, Taian, 271000, Shandong, China
| | - Y Duan
- Department of Hematology, The Second Affiliated Hospital of Shandong First Medical University, No. 706, Taishan Street, Taian, 271000, Shandong, China
| | - K Wang
- Research Service Office, The Second Affiliated Hospital of Shandong First Medical University, Taian, Shandong, China
| | - Q Kong
- Department of Hematology, The Second Affiliated Hospital of Shandong First Medical University, No. 706, Taishan Street, Taian, 271000, Shandong, China
| | - H Zhang
- Department of Hematology, The Second Affiliated Hospital of Shandong First Medical University, No. 706, Taishan Street, Taian, 271000, Shandong, China.
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18
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Hagiwara M, Yasumizu Y, Yamashita N, Rajabi H, Fushimi A, Long MD, Li W, Bhattacharya A, Ahmad R, Oya M, Liu S, Kufe D. MUC1-C Activates the BAF (mSWI/SNF) Complex in Prostate Cancer Stem Cells. Cancer Res 2020; 81:1111-1122. [PMID: 33323379 DOI: 10.1158/0008-5472.can-20-2588] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/12/2020] [Accepted: 12/09/2020] [Indexed: 12/23/2022]
Abstract
The Brg/Brahma-associated factor (BAF, mSWI/SNF) chromatin remodeling complex is of importance in development and has been linked to prostate oncogenesis. The oncogenic MUC1-C protein promotes lineage plasticity in the progression of neuroendocrine prostate cancer (NEPC), however, there is no known association between MUC1-C and BAF. We report here that MUC1-C binds directly to the E2F1 transcription factor and that the MUC1-C→E2F1 pathway induces expression of embryonic stem cell-specific BAF (esBAF) components BRG1, ARID1A, BAF60a, BAF155, and BAF170 in castrate-resistant prostate cancer (CRPC) and NEPC cells. In concert with this previously unrecognized pathway, MUC1 was associated with increased expression of E2F1 and esBAF components in NEPC tumors as compared with CRPC, supporting involvement of MUC1-C in activating the E2F1→esBAF pathway with progression to NEPC. MUC1-C formed a nuclear complex with BAF and activated cancer stem cell (CSC) gene signatures and the core pluripotency factor gene network. The MUC1-C→E2F1→BAF pathway was necessary for induction of both the NOTCH1 effector of CSC function and the NANOG pluripotency factor, and collectively, this network drove CSC self-renewal. These findings indicate that MUC1-C promotes NEPC progression by integrating activation of E2F1 and esBAF with induction of NOTCH1, NANOG, and stemness. SIGNIFICANCE: These findings show that MUC1-C, which promotes prostate cancer progression, activates a novel pathway that drives the BAF remodeling complex, induces NOTCH1 and NANOG, and promotes self-renewal of prostate cancer stem cells.
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Affiliation(s)
- Masayuki Hagiwara
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Yota Yasumizu
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Nami Yamashita
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Hasan Rajabi
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Atsushi Fushimi
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Mark D Long
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Wei Li
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | | | - Rehan Ahmad
- King Khalid University Hospital College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mototsugu Oya
- Department of Urology, Keio University School of Medicine, Tokyo, Japan
| | - Song Liu
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Donald Kufe
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts.
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19
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Wen Z, Zhang L, Ruan H, Li G. Histone variant H2A.Z regulates nucleosome unwrapping and CTCF binding in mouse ES cells. Nucleic Acids Res 2020; 48:5939-5952. [PMID: 32392318 PMCID: PMC7293034 DOI: 10.1093/nar/gkaa360] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 03/27/2020] [Accepted: 04/29/2020] [Indexed: 01/28/2023] Open
Abstract
Nucleosome is the basic structural unit of chromatin, and its dynamics plays critical roles in the regulation of genome functions. However, how the nucleosome structure is regulated by histone variants in vivo is still largely uncharacterized. Here, by employing Micrococcal nuclease (MNase) digestion of crosslinked chromatin followed by chromatin immunoprecipitation (ChIP) and paired-end sequencing (MNase-X-ChIP-seq), we mapped unwrapping states of nucleosomes containing histone variant H2A.Z in mouse embryonic stem (ES) cells. We found that H2A.Z nucleosomes are more enriched with unwrapping states compared with canonical nucleosomes. Interestingly, +1 H2A.Z nucleosomes with 30–80 bp DNA is correlated with less active genes compared with +1 H2A.Z nucleosomes with 120–140 bp DNA. We confirmed the unwrapping of H2A.Z nucleosomes under native condition by re-ChIP of H2A.Z and H2A after CTCF CUT&RUN in mouse ES cells. Importantly, we found that depletion of H2A.Z results in decreased unwrapping of H3.3 nucleosomes and increased CTCF binding. Taken together, through MNase-X-ChIP-seq, we showed that histone variant H2A.Z regulates nucleosome unwrapping in vivo and that its function in regulating transcription or CTCF binding is correlated with unwrapping states of H2A.Z nucleosomes.
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Affiliation(s)
- Zengqi Wen
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Liwei Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Haihe Ruan
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Guohong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing, China
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20
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Li L, Dai H, Nguyen AP, Hai R, Gu W. Influenza A virus utilizes noncanonical cap-snatching to diversify its mRNA/ncRNA. RNA (NEW YORK, N.Y.) 2020; 26:1170-1183. [PMID: 32444459 PMCID: PMC7430677 DOI: 10.1261/rna.073866.119] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Influenza A virus (IAV) utilizes cap-snatching to obtain host capped small RNAs for priming viral mRNA synthesis, generating capped hybrid mRNAs for translation. Previous studies have been focusing on canonical cap-snatching, which occurs at the very 5' end of viral mRNAs. Here we discovered noncanonical cap-snatching, which generates capped hybrid mRNAs/noncoding RNAs mapped to the region ∼300 nucleotides (nt) upstream of each mRNA 3' end, and to the 5' region, primarily starting at the second nt, of each virion RNAs (vRNA). Like canonical cap-snatching, noncanonical cap-snatching utilizes a base-pairing between the last nt G of host capped RNAs and a nt C of template RNAs to prime RNA synthesis. However, the nt upstream of this template C is usually A/U rather than just U; prime-realignment occurs less frequently. We also demonstrate that IAV can snatch capped IAV RNAs in addition to host RNAs. Noncanonical cap-snatching likely generates novel mRNAs with start AUG encoded in viral or host RNAs. These findings expand our understanding of cap-snatching mechanisms and suggest that IAV may utilize noncanonical cap-snatching to diversify its mRNAs/ncRNAs.
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Affiliation(s)
- Lichao Li
- Department of Molecular, Cell, and Systems Biology, University of California, Riverside, California 92521, USA
| | - Hui Dai
- Department of Molecular, Cell, and Systems Biology, University of California, Riverside, California 92521, USA
| | - An-Phong Nguyen
- Department of Molecular, Cell, and Systems Biology, University of California, Riverside, California 92521, USA
| | - Rong Hai
- Department of Microbiology and Plant Pathology, University of California, Riverside, California 92521, USA
| | - Weifeng Gu
- Department of Molecular, Cell, and Systems Biology, University of California, Riverside, California 92521, USA
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21
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Hildreth AE, Ellison MA, Francette AM, Seraly JM, Lotka LM, Arndt KM. The nucleosome DNA entry-exit site is important for transcription termination and prevention of pervasive transcription. eLife 2020; 9:e57757. [PMID: 32845241 PMCID: PMC7449698 DOI: 10.7554/elife.57757] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 08/09/2020] [Indexed: 12/21/2022] Open
Abstract
Compared to other stages in the RNA polymerase II transcription cycle, the role of chromatin in transcription termination is poorly understood. We performed a genetic screen in Saccharomyces cerevisiae to identify histone mutants that exhibit transcriptional readthrough of terminators. Amino acid substitutions identified by the screen map to the nucleosome DNA entry-exit site. The strongest H3 mutants revealed widespread genomic changes, including increased sense-strand transcription upstream and downstream of genes, increased antisense transcription overlapping gene bodies, and reduced nucleosome occupancy particularly at the 3' ends of genes. Replacement of the native sequence downstream of a gene with a sequence that increases nucleosome occupancy in vivo reduced readthrough transcription and suppressed the effect of a DNA entry-exit site substitution. Our results suggest that nucleosomes can facilitate termination by serving as a barrier to transcription and highlight the importance of the DNA entry-exit site in broadly maintaining the integrity of the transcriptome.
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Affiliation(s)
- A Elizabeth Hildreth
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| | - Mitchell A Ellison
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| | - Alex M Francette
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| | - Julia M Seraly
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| | - Lauren M Lotka
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
| | - Karen M Arndt
- Department of Biological Sciences, University of PittsburghPittsburghUnited States
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22
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Patty BJ, Hainer SJ. Non-Coding RNAs and Nucleosome Remodeling Complexes: An Intricate Regulatory Relationship. BIOLOGY 2020; 9:E213. [PMID: 32784701 PMCID: PMC7465399 DOI: 10.3390/biology9080213] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/30/2020] [Accepted: 08/06/2020] [Indexed: 12/17/2022]
Abstract
Eukaryotic genomes are pervasively transcribed, producing both coding and non-coding RNAs (ncRNAs). ncRNAs are diverse and a critical family of biological molecules, yet much remains unknown regarding their functions and mechanisms of regulation. ATP-dependent nucleosome remodeling complexes, in modifying chromatin structure, play an important role in transcriptional regulation. Recent findings show that ncRNAs regulate nucleosome remodeler activities at many levels and that ncRNAs are regulatory targets of nucleosome remodelers. Further, a series of recent screens indicate this network of regulatory interactions is more expansive than previously appreciated. Here, we discuss currently described regulatory interactions between ncRNAs and nucleosome remodelers and contextualize their biological functions.
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Affiliation(s)
| | - Sarah J. Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA;
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23
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Directed remodeling of the mouse gut microbiome inhibits the development of atherosclerosis. Nat Biotechnol 2020; 38:1288-1297. [PMID: 32541956 PMCID: PMC7641989 DOI: 10.1038/s41587-020-0549-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/07/2020] [Indexed: 02/07/2023]
Abstract
The gut microbiome is a malleable microbial community that can remodel in response to a number of factors, including diet, and contribute to the development of several chronic diseases, including atherosclerosis. We devised an in vitro screening protocol of the mouse gut microbiome to discover molecules that can selectively modify bacterial growth. This approach was used to identify cyclic d,l-α-peptides that remodeled the Western diet (WD) gut microbiome toward the low fat diet microbiome state. Daily oral administration of the peptides in WD-fed LDLr−/− mice reduced plasma total cholesterol levels and atherosclerotic plaques. Depletion of the microbiome with antibiotics abrogated these effects. Peptide treatment reprogrammed the microbiome transcriptome, suppressed the production of pro-inflammatory cytokines (including IL-6, TNF-α, and IL-1β), rebalanced levels of short-chain fatty acids and bile acids, improved gut barrier integrity, and increased intestinal T regulatory cells. Directed chemical manipulation provides an additional tool to decipher the chemical biology of the gut microbiome and may advance microbiome-targeted therapeutics.
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24
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Florentino RM, Fraunhoffer NA, Morita K, Takeishi K, Ostrowska A, Achreja A, Animasahun O, Haep N, Arazov S, Agarwal N, Collin de l'Hortet A, Guzman-Lepe J, Tafaleng EN, Mukherjee A, Troy K, Banerjee S, Paranjpe S, Michalopoulos GK, Bell A, Nagrath D, Hainer SJ, Fox IJ, Soto-Gutierrez A. Cellular Location of HNF4α is Linked With Terminal Liver Failure in Humans. Hepatol Commun 2020; 4:859-875. [PMID: 32490322 PMCID: PMC7262291 DOI: 10.1002/hep4.1505] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 12/12/2022] Open
Abstract
Hepatocyte nuclear factor 4 alpha (HNF4α) is a transcription factor that plays a critical role in hepatocyte function, and HNF4α‐based reprogramming corrects terminal liver failure in rats with chronic liver disease. In the livers of patients with advanced cirrhosis, HNF4α RNA expression levels decrease as hepatic function deteriorates, and protein expression is found in the cytoplasm. These findings could explain impaired hepatic function in patients with degenerative liver disease. In this study, we analyzed HNF4α localization and the pathways involved in post‐translational modification of HNF4α in human hepatocytes from patients with decompensated liver function. RNA‐sequencing analysis revealed that AKT‐related pathways, specifically phospho‐AKT, is down‐regulated in cirrhotic hepatocytes from patients with terminal failure, in whom nuclear levels of HNF4α were significantly reduced, and cytoplasmic expression of HNF4α was increased. cMET was also significantly reduced in failing hepatocytes. Moreover, metabolic profiling showed a glycolytic phenotype in failing human hepatocytes. The contribution of cMET and phospho‐AKT to nuclear localization of HNF4α was confirmed using Spearman's rank correlation test and pathway analysis, and further correlated with hepatic dysfunction by principal component analysis. HNF4α acetylation, a posttranslational modification important for nuclear retention, was also significantly reduced in failing human hepatocytes when compared with normal controls. Conclusion: These results suggest that the alterations in the cMET‐AKT pathway directly correlate with HNF4α localization and level of hepatocyte dysfunction. This study suggests that manipulation of HNF4α and pathways involved in HNF4α posttranslational modification may restore hepatocyte function in patients with terminal liver failure.
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Affiliation(s)
- Rodrigo M Florentino
- Department of Pathology University of Pittsburgh Pittsburgh PA.,Department of Physiology and Biophysics Universidade Federal de Minas Gerais Belo Horizonte Brazil
| | - Nicolas A Fraunhoffer
- Department of Pathology University of Pittsburgh Pittsburgh PA.,Facultad de Ciencias de la Salud Carrera de Medicina Universidad Maimónides Buenos Aires Argentina.,Centro de Estudios Farmacológicos y Botánicos-CONICET Buenos Aires Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires Argentina
| | - Kazutoyo Morita
- Department of Pathology University of Pittsburgh Pittsburgh PA
| | - Kazuki Takeishi
- Department of Pathology University of Pittsburgh Pittsburgh PA.,Department of Surgery and Science Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Alina Ostrowska
- Department of Surgery Children's Hospital of Pittsburgh of UPMC University of Pittsburgh Pittsburgh PA
| | - Abhinav Achreja
- Laboratory for Systems Biology of Human Diseases Department of Biomedical Engineering Biointerfaces Institute University of Michigan Ann Arbor MI
| | - Olamide Animasahun
- Laboratory for Systems Biology of Human Diseases Department of Biomedical Engineering Biointerfaces Institute University of Michigan Ann Arbor MI
| | - Nils Haep
- Department of Pathology University of Pittsburgh Pittsburgh PA
| | - Shohrat Arazov
- Department of Pathology University of Pittsburgh Pittsburgh PA
| | - Nandini Agarwal
- Department of Pathology University of Pittsburgh Pittsburgh PA.,School of Bioscience and Technology Vellore Institute of Technology Vellore India
| | | | | | - Edgar N Tafaleng
- Department of Surgery Children's Hospital of Pittsburgh of UPMC University of Pittsburgh Pittsburgh PA
| | - Amitava Mukherjee
- Department of Surgery Children's Hospital of Pittsburgh of UPMC University of Pittsburgh Pittsburgh PA
| | - Kris Troy
- Department of Biological Sciences University of Pittsburgh Pittsburgh PA
| | - Swati Banerjee
- Department of Pathology University of Pittsburgh Pittsburgh PA
| | | | | | - Aaron Bell
- Department of Pathology University of Pittsburgh Pittsburgh PA
| | - Deepak Nagrath
- Laboratory for Systems Biology of Human Diseases Department of Biomedical Engineering Biointerfaces Institute University of Michigan Ann Arbor MI.,Department of Chemical Engineering and Rogel Cancer Center University of Michigan Ann Arbor MI
| | - Sarah J Hainer
- Department of Biological Sciences University of Pittsburgh Pittsburgh PA
| | - Ira J Fox
- Department of Surgery Children's Hospital of Pittsburgh of UPMC University of Pittsburgh Pittsburgh PA
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25
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Xu J, Ma H, Ma H, Jiang W, Mela CA, Duan M, Zhao S, Gao C, Hahm ER, Lardo SM, Troy K, Sun M, Pai R, Stolz DB, Zhang L, Singh S, Brand RE, Hartman DJ, Hu J, Hainer SJ, Liu Y. Super-resolution imaging reveals the evolution of higher-order chromatin folding in early carcinogenesis. Nat Commun 2020; 11:1899. [PMID: 32313005 PMCID: PMC7171144 DOI: 10.1038/s41467-020-15718-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 03/26/2020] [Indexed: 12/24/2022] Open
Abstract
Genomic DNA is folded into a higher-order structure that regulates transcription and maintains genomic stability. Although progress has been made on understanding biochemical characteristics of epigenetic modifications in cancer, the in-situ higher-order folding of chromatin structure during malignant transformation remains largely unknown. Here, using optimized stochastic optical reconstruction microscopy (STORM) for pathological tissue (PathSTORM), we uncover a gradual decompaction and fragmentation of higher-order chromatin folding throughout all stages of carcinogenesis in multiple tumor types, and prior to tumor formation. Our integrated imaging, genomic, and transcriptomic analyses reveal functional consequences in enhanced transcription activities and impaired genomic stability. We also demonstrate the potential of imaging higher-order chromatin disruption to detect high-risk precursors that cannot be distinguished by conventional pathology. Taken together, our findings reveal gradual decompaction and fragmentation of higher-order chromatin structure as an enabling characteristic in early carcinogenesis to facilitate malignant transformation, which may improve cancer diagnosis, risk stratification, and prevention.
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Affiliation(s)
- Jianquan Xu
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Hongqiang Ma
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Hongbin Ma
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of General Surgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Dalian Jinzhou First People's Hospital, Dalian, China
| | - Wei Jiang
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of Pathology, West China Second University Hospital, Sichuan University, 610041, Chengdu, China
| | - Christopher A Mela
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Meihan Duan
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- School of Medicine, Tsinghua University, No.1 Tsinghua Yuan, Haidian District, 100084, Beijing, China
| | - Shimei Zhao
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of Pathology, School of Medicine, Guangxi University of Science and Technology, Guangxi, China
| | - Chenxi Gao
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
| | - Eun-Ryeong Hahm
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
| | - Santana M Lardo
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Kris Troy
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Ming Sun
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Reet Pai
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Donna B Stolz
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Lin Zhang
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
| | - Shivendra Singh
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
| | - Randall E Brand
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Douglas J Hartman
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Jing Hu
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Sarah J Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
| | - Yang Liu
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
- University of Pittsburgh Hillman Cancer Center, Pittsburgh, PA, 15232, USA.
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
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26
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Abstract
In eukaryotes, DNA is highly compacted within the nucleus into a structure known as chromatin. Modulation of chromatin structure allows for precise regulation of gene expression, and thereby controls cell fate decisions. Specific chromatin organization is established and preserved by numerous factors to generate desired cellular outcomes. In embryonic stem (ES) cells, chromatin is precisely regulated to preserve their two defining characteristics: self-renewal and pluripotent state. This action is accomplished by a litany of nucleosome remodelers, histone variants, epigenetic marks, and other chromatin regulatory factors. These highly dynamic regulatory factors come together to precisely define a chromatin state that is conducive to ES cell maintenance and development, where dysregulation threatens the survival and fitness of the developing organism.
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Affiliation(s)
- David C Klein
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, United States
| | - Sarah J Hainer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, United States.
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27
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Ho PJ, Lloyd SM, Bao X. Unwinding chromatin at the right places: how BAF is targeted to specific genomic locations during development. Development 2019; 146:146/19/dev178780. [PMID: 31570369 DOI: 10.1242/dev.178780] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The BAF (SWI/SNF) chromatin remodeling complex plays a crucial role in modulating spatiotemporal gene expression during mammalian development. Although its remodeling activity was characterized in vitro decades ago, the complex actions of BAF in vivo have only recently begun to be unraveled. In living cells, BAF only binds to and remodels a subset of genomic locations. This selectivity of BAF genomic targeting is crucial for cell-type specification and for mediating precise responses to environmental signals. Here, we provide an overview of the distinct molecular mechanisms modulating BAF chromatin binding, including its combinatory assemblies, DNA/histone modification-binding modules and post-translational modifications, as well as its interactions with proteins, RNA and lipids. This Review aims to serve as a primer for future studies to decode the actions of BAF in developmental processes.
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Affiliation(s)
- Patric J Ho
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Sarah M Lloyd
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Xiaomin Bao
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA .,Department of Dermatology, Northwestern University, Evanston, IL 60208, USA.,Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Evanston, IL 60208, USA
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28
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Gouot E, Bhat W, Rufiange A, Fournier E, Paquet E, Nourani A. Casein kinase 2 mediated phosphorylation of Spt6 modulates histone dynamics and regulates spurious transcription. Nucleic Acids Res 2019; 46:7612-7630. [PMID: 29905868 PMCID: PMC6125631 DOI: 10.1093/nar/gky515] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/24/2018] [Indexed: 12/14/2022] Open
Abstract
CK2 is an essential protein kinase implicated in various cellular processes. In this study, we address a potential role of this kinase in chromatin modulations associated with transcription. We found that CK2 depletion from yeast cells leads to replication-independent increase of histone H3K56 acetylation and global activation of H3 turnover in coding regions. This suggests a positive role of CK2 in maintenance/recycling of the histone H3/H4 tetramers during transcription. Interestingly, strand-specific RNA-seq analyses show that CK2 inhibits global cryptic promoters driving both sense and antisense transcription. This further indicates a role of CK2 in the modulation of chromatin during transcription. Next, we showed that CK2 interacts with the major histone chaperone Spt6, and phosphorylates it in vivo and in vitro. CK2 phosphorylation of Spt6 is required for its cellular levels, for the suppression of histone H3 turnover and for the inhibition of spurious transcription. Finally, we showed that CK2 and Spt6 phosphorylation sites are important to various transcriptional responses suggesting that cryptic intragenic and antisense transcript production are associated with a defective adaptation to environmental cues. Altogether, our data indicate that CK2 mediated phosphorylation of Spt6 regulates chromatin dynamics associated with transcription, and prevents aberrant transcription.
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Affiliation(s)
- Emmanuelle Gouot
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada
| | - Wajid Bhat
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada
| | - Anne Rufiange
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada
| | - Eric Fournier
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada.,CHU de Quebec Research Center - Laval University, Endocrinology and Nephrology CHUL, Québec, Québec, Canada
| | - Eric Paquet
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada.,CHU de Quebec Research Center - Laval University, Endocrinology and Nephrology CHUL, Québec, Québec, Canada.,The Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Amine Nourani
- Laval University Cancer Research Center, St-Patrick Research Group in Basic Oncology, Québec, Québec, Canada
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29
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Kubik S, Bruzzone MJ, Challal D, Dreos R, Mattarocci S, Bucher P, Libri D, Shore D. Opposing chromatin remodelers control transcription initiation frequency and start site selection. Nat Struct Mol Biol 2019; 26:744-754. [PMID: 31384063 DOI: 10.1038/s41594-019-0273-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/28/2019] [Indexed: 12/31/2022]
Abstract
Precise nucleosome organization at eukaryotic promoters is thought to be generated by multiple chromatin remodeler (CR) enzymes and to affect transcription initiation. Using an integrated analysis of chromatin remodeler binding and nucleosome occupancy following rapid remodeler depletion, we investigated the interplay between these enzymes and their impact on transcription in yeast. We show that many promoters are affected by multiple CRs that operate in concert or in opposition to position the key transcription start site (TSS)-associated +1 nucleosome. We also show that nucleosome movement after CR inactivation usually results from the activity of another CR and that in the absence of any remodeling activity, +1 nucleosomes largely maintain their positions. Finally, we present functional assays suggesting that +1 nucleosome positioning often reflects a trade-off between maximizing RNA polymerase recruitment and minimizing transcription initiation at incorrect sites. Our results provide a detailed picture of fundamental mechanisms linking promoter nucleosome architecture to transcription initiation.
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Affiliation(s)
- Slawomir Kubik
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), Geneva, Switzerland
| | - Maria Jessica Bruzzone
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), Geneva, Switzerland
| | - Drice Challal
- Institut Jacques Monod, CNRS-Université Paris Diderot, Paris, France
| | - René Dreos
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Stefano Mattarocci
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), Geneva, Switzerland
| | - Philipp Bucher
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Domenico Libri
- Institut Jacques Monod, CNRS-Université Paris Diderot, Paris, France
| | - David Shore
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), Geneva, Switzerland.
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30
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Feldman JL, Peterson CL. Yeast Sirtuin Family Members Maintain Transcription Homeostasis to Ensure Genome Stability. Cell Rep 2019; 27:2978-2989.e5. [PMID: 31167142 PMCID: PMC6640630 DOI: 10.1016/j.celrep.2019.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 04/09/2019] [Accepted: 05/01/2019] [Indexed: 01/08/2023] Open
Abstract
The mammalian sirtuin, SIRT6, is a key tumor suppressor that maintains genome stability and regulates transcription, though how SIRT6 family members control genome stability is unclear. Here, we use multiple genome-wide approaches to demonstrate that the yeast SIRT6 homologs, Hst3 and Hst4, prevent genome instability by tuning levels of both coding and noncoding transcription. While nascent RNAs are elevated in the absence of Hst3 and Hst4, a global impact on steady-state mRNAs is masked by the nuclear exosome, indicating that sirtuins and the exosome provide two levels of regulation to maintain transcription homeostasis. We find that, in the absence of Hst3 and Hst4, increased transcription is associated with excessive DNA-RNA hybrids (R-loops) that appear to lead to new DNA double-strand breaks. Importantly, dissolution of R-loops suppresses the genome instability phenotypes of hst3 hst4 mutants, suggesting that the sirtuins maintain genome stability by acting as a rheostat to prevent promiscuous transcription.
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Affiliation(s)
- Jessica L Feldman
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Craig L Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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31
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Bracken AP, Brien GL, Verrijzer CP. Dangerous liaisons: interplay between SWI/SNF, NuRD, and Polycomb in chromatin regulation and cancer. Genes Dev 2019; 33:936-959. [PMID: 31123059 PMCID: PMC6672049 DOI: 10.1101/gad.326066.119] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In this review, Bracken et al. discuss the functional organization and biochemical activities of remodelers and Polycomb and explore how they work together to control cell differentiation and the maintenance of cell identity. They also discuss how mutations in the genes encoding these various chromatin regulators contribute to oncogenesis by disrupting the chromatin equilibrium. Changes in chromatin structure mediated by ATP-dependent nucleosome remodelers and histone modifying enzymes are integral to the process of gene regulation. Here, we review the roles of the SWI/SNF (switch/sucrose nonfermenting) and NuRD (nucleosome remodeling and deacetylase) and the Polycomb system in chromatin regulation and cancer. First, we discuss the basic molecular mechanism of nucleosome remodeling, and how this controls gene transcription. Next, we provide an overview of the functional organization and biochemical activities of SWI/SNF, NuRD, and Polycomb complexes. We describe how, in metazoans, the balance of these activities is central to the proper regulation of gene expression and cellular identity during development. Whereas SWI/SNF counteracts Polycomb, NuRD facilitates Polycomb repression on chromatin. Finally, we discuss how disruptions of this regulatory equilibrium contribute to oncogenesis, and how new insights into the biological functions of remodelers and Polycombs are opening avenues for therapeutic interventions on a broad range of cancer types.
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Affiliation(s)
- Adrian P Bracken
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Gerard L Brien
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - C Peter Verrijzer
- Department of Biochemistry, Erasmus University Medical Center, 3000 DR Rotterdam, the Netherlands
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32
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Long Noncoding RNA MALAT1 Acts as a Competing Endogenous RNA to Regulate TGF- β2 Induced Epithelial-Mesenchymal Transition of Lens Epithelial Cells by a MicroRNA-26a-Dependent Mechanism. BIOMED RESEARCH INTERNATIONAL 2019; 2019:1569638. [PMID: 31143769 PMCID: PMC6501259 DOI: 10.1155/2019/1569638] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 03/31/2019] [Accepted: 04/08/2019] [Indexed: 02/07/2023]
Abstract
The aim of the present study was to characterize whether the long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/miR-26a/Smad4 axis is involved in epithelial–mesenchymal transition (EMT) of lens epithelial cells (LECs). Primary human LECs were separated and cultured. Microarray analysis showed that a total of 568 lncRNAs are differentially expressed in primary HLECs in the presence of TGF-β2 and MALAT1 is mostly significantly dysregulated lncRNAs, which is increased by nearly 17-fold. In addition, upregulation of MALAT1 and downregulation of miR-26a were detected in human posterior capsule opacification (PCO) attached LECs and the LECs obtained from patients with anterior polar cataracts by quantitative RT-PCR (qRT-PCR). Next, our results showed that TGF-β2 induces overexpression of EMT markers in primary HLECs via a MALAT1-dependent mechanism. The mechanism is that MALAT1 negatively regulates miR-26a and miR-26a directly targets Smad4 by luciferase reporter assays and RNA-binding protein immunoprecipitation assay. In summary, TGF-β2 induces MALAT1 overexpression, which in turn MALAT1 acts as a ceRNA targeting Smad4 by binding miR-26a and promotes the progression of EMT of LECs.
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33
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Hainer SJ, Bošković A, McCannell KN, Rando OJ, Fazzio TG. Profiling of Pluripotency Factors in Single Cells and Early Embryos. Cell 2019; 177:1319-1329.e11. [PMID: 30955888 DOI: 10.1016/j.cell.2019.03.014] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/13/2019] [Accepted: 03/05/2019] [Indexed: 02/09/2023]
Abstract
Cell fate decisions are governed by sequence-specific transcription factors (TFs) that act in small populations of cells within developing embryos. To understand their functions in vivo, it is important to identify TF binding sites in these cells. However, current methods cannot profile TFs genome-wide at or near the single-cell level. Here we adapt the cleavage under targets and release using nuclease (CUT&RUN) method to profile TFs in low cell numbers, including single cells and individual pre-implantation embryos. Single-cell experiments suggest that only a fraction of TF binding sites are occupied in most cells, in a manner broadly consistent with measurements of peak intensity from multi-cell studies. We further show that chromatin binding by the pluripotency TF NANOG is highly dependent on the SWI/SNF chromatin remodeling complex in individual blastocysts but not in cultured cells. Ultra-low input CUT&RUN (uliCUT&RUN) therefore enables interrogation of TF binding from rare cell populations of particular importance in development or disease.
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Affiliation(s)
- Sarah J Hainer
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| | - Ana Bošković
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Kurtis N McCannell
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Oliver J Rando
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Thomas G Fazzio
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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34
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Schlesinger S, Meshorer E. Open Chromatin, Epigenetic Plasticity, and Nuclear Organization in Pluripotency. Dev Cell 2019; 48:135-150. [DOI: 10.1016/j.devcel.2019.01.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/30/2018] [Accepted: 12/31/2018] [Indexed: 12/27/2022]
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35
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Mana-Capelli S, McCollum D. Angiomotins stimulate LATS kinase autophosphorylation and act as scaffolds that promote Hippo signaling. J Biol Chem 2018; 293:18230-18241. [PMID: 30266805 DOI: 10.1074/jbc.ra118.004187] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 09/17/2018] [Indexed: 01/31/2023] Open
Abstract
The Hippo pathway controls cell proliferation, differentiation, and survival by regulating the Yes-associated protein (YAP) transcriptional coactivator in response to various stimuli, including the mechanical environment. The major YAP regulators are the LATS1/2 kinases, which phosphorylate and inhibit YAP. LATS1/2 are activated by phosphorylation on a hydrophobic motif (HM) outside of the kinase domain by MST1/2 and other kinases. Phosphorylation of the HM motif then triggers autophosphorylation of the kinase in the activation loop to fully activate the kinase, a process facilitated by MOB1. The angiomotin family of proteins (AMOT, AMOTL1, and AMOTL2) bind LATS1/2 and promote its kinase activity and YAP phosphorylation through an unknown mechanism. Here we show that angiomotins increase Hippo signaling through multiple mechanisms. We found that, by binding LATS1/2, SAV1, and YAP, angiomotins function as a scaffold that connects LATS1/2 to both its activator SAV1-MST1 and its target YAP. Deletion of all three angiomotins reduced the association of LATS1 with SAV1-MST1 and decreased MST1/2-mediated LATS1/2-HM phosphorylation. Angiomotin deletion also reduced LATS1/2's ability to associate with and phosphorylate YAP. In addition, we found that angiomotins have an unexpected function along with MOB1 to promote autophosphorylation of LATS1/2 on the activation loop motif independent of HM phosphorylation. These results indicate that angiomotins enhance Hippo signaling by stimulating LATS1/2 autophosphorylation and by connecting LATS1/2 with both its activator SAV1-MST1/2 and its substrate YAP.
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Affiliation(s)
- Sebastian Mana-Capelli
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605
| | - Dannel McCollum
- From the Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts 01605.
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36
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Dong N, Xu B, Shi H. Long noncoding RNA MALAT1 acts as a competing endogenous RNA to regulate Amadori-glycated albumin-induced MCP-1 expression in retinal microglia by a microRNA-124-dependent mechanism. Inflamm Res 2018; 67:913-925. [PMID: 30151700 DOI: 10.1007/s00011-018-1184-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 08/17/2018] [Accepted: 08/22/2018] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVE To determine whether the long noncoding RNA MALAT1 may be involved in the inflammatory effect of Amadori-glycated albumin (AGA) in retinal microglia via a microRNA-124 (miR-124)-dependent mechanism. METHODS Diabetes mellitus was induced by streptozotocin (STZ) injection. The expression of monocyte chemotactic protein-1 (MCP-1) in the retinas of rats was determined using quantitative reverse transcription-PCR (qRT-PCR) analyses and enzyme-linked immunosorbent assay (ELISA). Both qRT-PCR and ELISA were used to detect the levels of MCP-1 mRNA and soluble MCP-1 protein in the primary rat retinal microglia treated with AGA. The regulation of a putative target of miR-124 was validated by luciferase reporter assays. RESULTS MALAT1 knockdown ameliorated diabetic retinopathy (DR) and inhibited MCP-1 release in the retinas of STZ-induced diabetic rats. The cultured retinal microglial cells treated with AGA-released MCP-1 in a dose- and time-dependent manner. In addition, AGA consistently induced MALAT1 expression in the retinal microglial cells. Next, we demonstrated that the expression of MCP-1 is controlled by miR-124, which binds to the 3'-UTR of MCP-1 in microglial cells. Luciferase reporter assays and RNA-binding protein immunoprecipitation assays showed that MALAT1 targets miR-124. Finally, we demonstrated that MALAT1 acts as a competing endogenous RNA by directly binding to miR-124 to regulate AGA-induced MCP-1 expression in microglial cells. CONCLUSIONS MALAT1-miR-124-MCP-1 signaling pathway may be involved in AGA-induced MCP-1 expression in microglial cells, which may provide a new approach for the treatment of DR.
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Affiliation(s)
- Ning Dong
- Department of Ophthalmology, Beijing Friendship Hospital, Capital Medical University, Beijing, People's Republic of China.
| | - Bing Xu
- Department of Ophthalmology, Beijing Shijitan Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Hong Shi
- Department of Ophthalmology, Beijing Shijitan Hospital, Capital Medical University, Beijing, People's Republic of China
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37
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Tuck AC, Natarajan KN, Rice GM, Borawski J, Mohn F, Rankova A, Flemr M, Wenger A, Nutiu R, Teichmann S, Bühler M. Distinctive features of lincRNA gene expression suggest widespread RNA-independent functions. Life Sci Alliance 2018; 1:e201800124. [PMID: 30456373 PMCID: PMC6238598 DOI: 10.26508/lsa.201800124] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 07/13/2018] [Accepted: 07/13/2018] [Indexed: 02/06/2023] Open
Abstract
Eukaryotic genomes produce RNAs lacking protein-coding potential, with enigmatic roles. We integrated three approaches to study large intervening noncoding RNA (lincRNA) gene functions. First, we profiled mouse embryonic stem cells and neural precursor cells at single-cell resolution, revealing lincRNAs expressed in specific cell types, cell subpopulations, or cell cycle stages. Second, we assembled a transcriptome-wide atlas of nuclear lincRNA degradation by identifying targets of the exosome cofactor Mtr4. Third, we developed a reversible depletion system to separate the role of a lincRNA gene from that of its RNA. Our approach distinguished lincRNA loci functioning in trans from those modulating local gene expression. Some genes express stable and/or abundant lincRNAs in single cells, but many prematurely terminate transcription and produce lincRNAs rapidly degraded by the nuclear exosome. This suggests that besides RNA-dependent functions, lincRNA loci act as DNA elements or through transcription. Our integrative approach helps distinguish these mechanisms.
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Affiliation(s)
- Alex C Tuck
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK
| | - Kedar Nath Natarajan
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK.,Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK.,Danish Institute of Advanced Study and Functional Genomics and Metabolism Unit, University of Southern Denmark, Denmark
| | - Greggory M Rice
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Jason Borawski
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Fabio Mohn
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Aneliya Rankova
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Matyas Flemr
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Alice Wenger
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Razvan Nutiu
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Sarah Teichmann
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK.,Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, UK
| | - Marc Bühler
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
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38
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Dutta S, Mana-Capelli S, Paramasivam M, Dasgupta I, Cirka H, Billiar K, McCollum D. TRIP6 inhibits Hippo signaling in response to tension at adherens junctions. EMBO Rep 2018; 19:337-350. [PMID: 29222344 PMCID: PMC5797958 DOI: 10.15252/embr.201744777] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/13/2017] [Accepted: 11/15/2017] [Indexed: 11/09/2022] Open
Abstract
The transcriptional co-activator YAP controls cell proliferation, survival, and tissue regeneration in response to changes in the mechanical environment. It is not known how mechanical stimuli such as tension are sensed and how the signal is transduced to control YAP activity. Here, we show that the LIM domain protein TRIP6 acts as part of a mechanotransduction pathway at adherens junctions to promote YAP activity by inhibiting the LATS1/2 kinases. Previous studies showed that vinculin at adherens junctions becomes activated by mechanical tension. We show that vinculin inhibits Hippo signaling by recruiting TRIP6 to adherens junctions and stimulating its binding to and inhibition of LATS1/2 in response to tension. TRIP6 competes with MOB1 for binding to LATS1/2 thereby blocking MOB1 from recruiting the LATS1/2 activating kinases MST1/2. Together, these findings reveal a novel pathway that responds to tension at adherens junctions to control Hippo pathway signaling.
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Affiliation(s)
- Shubham Dutta
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Sebastian Mana-Capelli
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Murugan Paramasivam
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ishani Dasgupta
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Heather Cirka
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Kris Billiar
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
| | - Dannel McCollum
- Department of Biochemistry & Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
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39
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Acharya D, Hainer SJ, Yoon Y, Wang F, Bach I, Rivera-Pérez JA, Fazzio TG. KAT-Independent Gene Regulation by Tip60 Promotes ESC Self-Renewal but Not Pluripotency. Cell Rep 2018; 19:671-679. [PMID: 28445719 DOI: 10.1016/j.celrep.2017.04.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 03/01/2017] [Accepted: 03/30/2017] [Indexed: 12/11/2022] Open
Abstract
Although histone-modifying enzymes are generally assumed to function in a manner dependent on their enzymatic activities, this assumption remains untested for many factors. Here, we show that the Tip60 (Kat5) lysine acetyltransferase (KAT), which is essential for embryonic stem cell (ESC) self-renewal and pre-implantation development, performs these functions independently of its KAT activity. Unlike ESCs depleted of Tip60, KAT-deficient ESCs exhibited minimal alterations in gene expression, chromatin accessibility at Tip60 binding sites, and self-renewal, thus demonstrating a critical KAT-independent role of Tip60 in ESC maintenance. In contrast, KAT-deficient ESCs exhibited impaired differentiation into mesoderm and endoderm, demonstrating a KAT-dependent function in differentiation. Consistent with this phenotype, KAT-deficient mouse embryos exhibited post-implantation developmental defects. These findings establish separable KAT-dependent and KAT-independent functions of Tip60 in ESCs and during differentiation, revealing a complex repertoire of regulatory functions for this essential chromatin remodeling complex.
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Affiliation(s)
- Diwash Acharya
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Sarah J Hainer
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Yeonsoo Yoon
- Division of Genes and Development, Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Feng Wang
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ingolf Bach
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Jaime A Rivera-Pérez
- Division of Genes and Development, Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Thomas G Fazzio
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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40
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Archacki R, Yatusevich R, Buszewicz D, Krzyczmonik K, Patryn J, Iwanicka-Nowicka R, Biecek P, Wilczynski B, Koblowska M, Jerzmanowski A, Swiezewski S. Arabidopsis SWI/SNF chromatin remodeling complex binds both promoters and terminators to regulate gene expression. Nucleic Acids Res 2017; 45:3116-3129. [PMID: 27994035 PMCID: PMC5389626 DOI: 10.1093/nar/gkw1273] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 12/08/2016] [Indexed: 12/23/2022] Open
Abstract
ATP-dependent chromatin remodeling complexes are important regulators of gene expression in Eukaryotes. In plants, SWI/SNF-type complexes have been shown critical for transcriptional control of key developmental processes, growth and stress responses. To gain insight into mechanisms underlying these roles, we performed whole genome mapping of the SWI/SNF catalytic subunit BRM in Arabidopsis thaliana, combined with transcript profiling experiments. Our data show that BRM occupies thousands of sites in Arabidopsis genome, most of which located within or close to genes. Among identified direct BRM transcriptional targets almost equal numbers were up- and downregulated upon BRM depletion, suggesting that BRM can act as both activator and repressor of gene expression. Interestingly, in addition to genes showing canonical pattern of BRM enrichment near transcription start site, many other genes showed a transcription termination site-centred BRM occupancy profile. We found that BRM-bound 3΄ gene regions have promoter-like features, including presence of TATA boxes and high H3K4me3 levels, and possess high antisense transcriptional activity which is subjected to both activation and repression by SWI/SNF complex. Our data suggest that binding to gene terminators and controlling transcription of non-coding RNAs is another way through which SWI/SNF complex regulates expression of its targets.
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Affiliation(s)
- Rafal Archacki
- Laboratory of Systems Biology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.,Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Ruslan Yatusevich
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Daniel Buszewicz
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Katarzyna Krzyczmonik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Jacek Patryn
- Laboratory of Systems Biology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.,College of Inter-FacultyIndividual Studies in Mathematics and Natural Sciences, Warsaw 02-089, Poland
| | - Roksana Iwanicka-Nowicka
- Laboratory of Systems Biology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.,Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Przemyslaw Biecek
- Institute of Informatics, Faculty of Mathematics, Informatics and Mechanics,University of Warsaw, Warsaw 02-097, Poland.,Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw 00-662, Poland
| | - Bartek Wilczynski
- Institute of Informatics, Faculty of Mathematics, Informatics and Mechanics,University of Warsaw, Warsaw 02-097, Poland
| | - Marta Koblowska
- Laboratory of Systems Biology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.,Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Andrzej Jerzmanowski
- Laboratory of Systems Biology, Faculty of Biology, University of Warsaw, Warsaw 02-096, Poland.,Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
| | - Szymon Swiezewski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw 02-106, Poland
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41
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Krzyczmonik K, Wroblewska-Swiniarska A, Swiezewski S. Developmental transitions in Arabidopsis are regulated by antisense RNAs resulting from bidirectionally transcribed genes. RNA Biol 2017; 14:838-842. [PMID: 28513325 DOI: 10.1080/15476286.2017.1327112] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Transcription terminators are DNA elements located at the 3' end of genes that ensure efficient cleavage of nascent RNA generating the 3' end of mRNA, as well as facilitating disengagement of elongating DNA-dependent RNA polymerase II. Surprisingly, terminators are also a potent source of antisense transcription. We have recently described an Arabidopsis antisense transcript originating from the 3' end of a master regulator of Arabidopsis thaliana seed dormancy DOG1. In this review, we discuss the broader implications of our discovery in light of recent developments in yeast and Arabidopsis. We show that, surprisingly, the key features of terminators that give rise to antisense transcription are preserved between Arabidopsis and yeast, suggesting a conserved mechanism. We also compare our discovery to known antisense-based regulatory mechanisms, highlighting the link between antisense-based gene expression regulation and major developmental transitions in plants.
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Affiliation(s)
| | | | - Szymon Swiezewski
- a Department of Protein Biosynthesis , Institute of Biochemistry and Biophysics , Warsaw , Poland
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42
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King HW, Klose RJ. The pioneer factor OCT4 requires the chromatin remodeller BRG1 to support gene regulatory element function in mouse embryonic stem cells. eLife 2017; 6:22631. [PMID: 28287392 PMCID: PMC5400504 DOI: 10.7554/elife.22631] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 03/09/2017] [Indexed: 12/19/2022] Open
Abstract
Pioneer transcription factors recognise and bind their target sequences in inaccessible chromatin to establish new transcriptional networks throughout development and cellular reprogramming. During this process, pioneer factors establish an accessible chromatin state to facilitate additional transcription factor binding, yet it remains unclear how different pioneer factors achieve this. Here, we discover that the pluripotency-associated pioneer factor OCT4 binds chromatin to shape accessibility, transcription factor co-binding, and regulatory element function in mouse embryonic stem cells. Chromatin accessibility at OCT4-bound sites requires the chromatin remodeller BRG1, which is recruited to these sites by OCT4 to support additional transcription factor binding and expression of the pluripotency-associated transcriptome. Furthermore, the requirement for BRG1 in shaping OCT4 binding reflects how these target sites are used during cellular reprogramming and early mouse development. Together this reveals a distinct requirement for a chromatin remodeller in promoting the activity of the pioneer factor OCT4 and regulating the pluripotency network. DOI:http://dx.doi.org/10.7554/eLife.22631.001 All cells in your body contain the same genetic information in the form of genes encoded within DNA. Yet, cells use this information in different ways so that the activities of individual genes within that DNA can vary from cell to cell. This allows identical cells to become different to each other and to adapt to changing circumstances. A group of proteins called transcription factors control the activity of certain genes by binding to specific sites on DNA. However, this isn’t a straightforward process because DNA in human and other animal cells is usually associated with structures called nucleosomes that can block access to the DNA. Pioneer transcription factors, such as OCT4, are a specific group of transcription factors that can attach to DNA in spite of the nucleosomes, but it’s not clear how this is possible. Once pioneer transcription factors attach to DNA they can help other transcription factors to bind alongside them. King et al. studied OCT4 in stem cells from mouse embryos to investigate how it is able to act as a pioneer transcription factor and control gene activity. The experiments show that several other transcription factors lose the ability to bind to DNA when OCT4 is absent. This leads to widespread changes in gene activity in the cells, which seems to be due to other transcription factors being unable to get past the nucleosomes to attach to the DNA. Further experiments showed that OCT4 needs a protein called BRG1 in order to act as a pioneer transcription factor. BRG1 is an enzyme that is able to move and remove (remodel) nucleosomes attached to DNA, suggesting that normal transcription factor binding requires this activity. The next challenge is to investigate whether BRG1, or similar enzymes, are also needed by other pioneer transcription factors that are required for normal gene activity and cell identity. This will be important because many enzymes that remodel nucleosomes are disrupted in human diseases like cancer where cells lose their normal identity. DOI:http://dx.doi.org/10.7554/eLife.22631.002
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Affiliation(s)
- Hamish W King
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Robert J Klose
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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43
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Miller EL, Hargreaves DC, Kadoch C, Chang CY, Calarco JP, Hodges C, Buenrostro JD, Cui K, Greenleaf WJ, Zhao K, Crabtree GR. TOP2 synergizes with BAF chromatin remodeling for both resolution and formation of facultative heterochromatin. Nat Struct Mol Biol 2017; 24:344-352. [PMID: 28250416 PMCID: PMC5395302 DOI: 10.1038/nsmb.3384] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 02/01/2017] [Indexed: 12/19/2022]
Abstract
Resolution and formation of facultative heterochromatin is essential to development, reprogramming, and oncogenesis. The mechanisms underlying these changes are poorly understood due to the inability to study heterochromatin dynamics and structure in vivo. We devised an in vivo approach to investigate these mechanisms and found that topoisomerase II (TOP2), but not TOP1, synergizes with BAF (mSWI/SNF) ATP-dependent chromatin remodeling complexes genome-wide to resolve facultative heterochromatin to accessible chromatin independent of transcription, indicating that changes in DNA topology through (de-)catenation rather than release of torsional stress through swiveling is necessary for heterochromatin resolution. In turn, TOP2 and BAF cooperate to recruit pluripotency factors, explaining some of the instructive roles of BAF complexes. Unexpectedly, we found that TOP2, also plays a role in the reformation of facultative heterochromatin, suggesting that facultative heterochromatin and accessible chromatin exist at different states of catenation or other topologies, which may be critical to their structures.
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Affiliation(s)
- Erik L Miller
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA.,Department of Genetics, Stanford University School of Medicine, Stanford, California, USA
| | - Diana C Hargreaves
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Cigall Kadoch
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Chiung-Ying Chang
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Joseph P Calarco
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Courtney Hodges
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Jason D Buenrostro
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA.,Harvard Society of Fellows, Harvard University, Cambridge, Massachusetts, USA
| | - Kairong Cui
- Systems Biology Center, National Heart, Lung, and Blood Institute, US National Institutes of Health, Bethesda, Maryland, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University School of Medicine, Stanford, California, USA
| | - Keji Zhao
- Systems Biology Center, National Heart, Lung, and Blood Institute, US National Institutes of Health, Bethesda, Maryland, USA
| | - Gerald R Crabtree
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA.,Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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44
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Hainer SJ, McCannell KN, Yu J, Ee LS, Zhu LJ, Rando OJ, Fazzio TG. DNA methylation directs genomic localization of Mbd2 and Mbd3 in embryonic stem cells. eLife 2016; 5. [PMID: 27849519 PMCID: PMC5111885 DOI: 10.7554/elife.21964] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/01/2016] [Indexed: 12/22/2022] Open
Abstract
Cytosine methylation is an epigenetic and regulatory mark that functions in part through recruitment of chromatin remodeling complexes containing methyl-CpG binding domain (MBD) proteins. Two MBD proteins, Mbd2 and Mbd3, were previously shown to bind methylated or hydroxymethylated DNA, respectively; however, both of these findings have been disputed. Here, we investigated this controversy using experimental approaches and re-analysis of published data and find no evidence for methylation-independent functions of Mbd2 or Mbd3. We show that chromatin localization of Mbd2 and Mbd3 is highly overlapping and, unexpectedly, we find Mbd2 and Mbd3 are interdependent for chromatin association. Further investigation reveals that both proteins are required for normal levels of cytosine methylation and hydroxymethylation in murine embryonic stem cells. Furthermore, Mbd2 and Mbd3 regulate overlapping sets of genes that are also regulated by DNA methylation/hydroxymethylation factors. These findings reveal an interdependent regulatory mechanism mediated by the DNA methylation machinery and its readers.
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Affiliation(s)
- Sarah J Hainer
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States
| | - Kurtis N McCannell
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States
| | - Jun Yu
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States
| | - Ly-Sha Ee
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States
| | - Lihua J Zhu
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
| | - Oliver J Rando
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, United States
| | - Thomas G Fazzio
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Medical School, Worcester, United States.,Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, United States
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45
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Wei MM, Zhou GB. Long Non-coding RNAs and Their Roles in Non-small-cell Lung Cancer. GENOMICS, PROTEOMICS & BIOINFORMATICS 2016; 14:280-288. [PMID: 27397102 PMCID: PMC5093404 DOI: 10.1016/j.gpb.2016.03.007] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/24/2016] [Accepted: 03/01/2016] [Indexed: 12/25/2022]
Abstract
As a leading cause of cancer deaths worldwide, lung cancer is a collection of diseases with diverse etiologies which can be broadly classified into small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). Lung cancer is characterized by genomic and epigenomic alterations; however, mechanisms underlying lung tumorigenesis remain to be elucidated. Long non-coding RNAs (lncRNAs) are a group of non-coding RNAs that consist of ⩾200 nucleotides but possess low or no protein-coding potential. Accumulating evidence indicates that abnormal expression of lncRNAs is associated with tumorigenesis of various cancers, including lung cancer, through multiple biological mechanisms involving epigenetic, transcriptional, and post-transcriptional alterations. In this review, we highlight the expression and roles of lncRNAs in NSCLC and discuss their potential clinical applications as diagnostic or prognostic biomarkers, as well as therapeutic targets.
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Affiliation(s)
- Ming-Ming Wei
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guang-Biao Zhou
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
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46
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Toto PC, Puri PL, Albini S. SWI/SNF-directed stem cell lineage specification: dynamic composition regulates specific stages of skeletal myogenesis. Cell Mol Life Sci 2016; 73:3887-96. [PMID: 27207468 PMCID: PMC5158306 DOI: 10.1007/s00018-016-2273-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 11/25/2022]
Abstract
SWI/SNF chromatin-remodeling complexes are key regulators of the epigenetic modifications that determine whether stem cells maintain pluripotency or commit toward specific lineages through development and during postnatal life. Dynamic combinatorial assembly of multiple variants of SWI/SNF subunits is emerging as the major determinant of the functional versatility of SWI/SNF. Here, we summarize the current knowledge on the structural and functional properties of the alternative SWI/SNF complexes that direct stem cell fate toward skeletal muscle lineage and control distinct stages of skeletal myogenesis. In particular, we will refer to recent evidence pointing to the essential role of two SWI/SNF components not expressed in embryonic stem cells-the catalytic subunit BRM and the structural component BAF60C-whose induction in muscle progenitors coincides with the expansion of their transcriptional repertoire.
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Affiliation(s)
- Paula Coutinho Toto
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA
| | - Pier Lorenzo Puri
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA.
- IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano, 64, 00143, Rome, Italy.
| | - Sonia Albini
- Sanford Burnham Prebys Medical Discovery Institute, 10905 Road to the Cure, San Diego, CA, 92121, USA.
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47
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C Quaresma AJ, Bugai A, Barboric M. Cracking the control of RNA polymerase II elongation by 7SK snRNP and P-TEFb. Nucleic Acids Res 2016; 44:7527-39. [PMID: 27369380 PMCID: PMC5027500 DOI: 10.1093/nar/gkw585] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 06/17/2016] [Indexed: 01/01/2023] Open
Abstract
Release of RNA polymerase II (Pol II) from promoter-proximal pausing has emerged as a critical step regulating gene expression in multicellular organisms. The transition of Pol II into productive elongation requires the kinase activity of positive transcription elongation factor b (P-TEFb), which is itself under a stringent control by the inhibitory 7SK small nuclear ribonucleoprotein (7SK snRNP) complex. Here, we provide an overview on stimulating Pol II pause release by P-TEFb and on sequestering P-TEFb into 7SK snRNP. Furthermore, we highlight mechanisms that govern anchoring of 7SK snRNP to chromatin as well as means that release P-TEFb from the inhibitory complex, and propose a unifying model of P-TEFb activation on chromatin. Collectively, these studies shine a spotlight on the central role of RNA binding proteins (RBPs) in directing the inhibition and activation of P-TEFb, providing a compelling paradigm for controlling Pol II transcription with a non-coding RNA.
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Affiliation(s)
- Alexandre J C Quaresma
- Medicum, Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Andrii Bugai
- Medicum, Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
| | - Matjaz Barboric
- Medicum, Department of Biochemistry and Developmental Biology, University of Helsinki, Helsinki FIN-00014, Finland
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48
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Flynn RA, Do BT, Rubin AJ, Calo E, Lee B, Kuchelmeister H, Rale M, Chu C, Kool ET, Wysocka J, Khavari PA, Chang HY. 7SK-BAF axis controls pervasive transcription at enhancers. Nat Struct Mol Biol 2016; 23:231-8. [PMID: 26878240 PMCID: PMC4982704 DOI: 10.1038/nsmb.3176] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 01/20/2016] [Indexed: 01/08/2023]
Abstract
RNA functions at enhancers remain mysterious. Here we show that the 7SK small nuclear RNA (snRNA) inhibits enhancer transcription by modulating nucleosome position. 7SK occupies enhancers and super enhancers genome-wide in mouse and human cells, and 7SK is required to limit eRNA initiation and synthesis in a manner distinct from promoter pausing. Clustered elements at super enhancers uniquely require 7SK to prevent convergent transcription and DNA damage signaling. 7SK physically interacts with the BAF chromatin remodeling complex, recruit BAF to enhancers, and inhibits enhancer transcription by modulating chromatin structure. In turn, 7SK occupancy at enhancers coincides with Brd4 and is exquisitely sensitive to the bromodomain inhibitor JQ1. Thus, 7SK employs distinct mechanisms to counteract diverse consequences of pervasive transcription that distinguish super enhancers, enhancers, and promoters.
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Affiliation(s)
- Ryan A Flynn
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, California, USA.,Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Brian T Do
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, California, USA.,Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Adam J Rubin
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Eliezer Calo
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Byron Lee
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, California, USA.,Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | | | - Michael Rale
- The Genome Institute, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Ci Chu
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, California, USA.,Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Eric T Kool
- Department of Chemistry, Stanford University, Stanford, California, USA
| | - Joanna Wysocka
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Paul A Khavari
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
| | - Howard Y Chang
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, California, USA.,Program in Epithelial Biology, Stanford University School of Medicine, Stanford, California, USA
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49
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Systematic approaches to identify functional lncRNAs. Curr Opin Genet Dev 2016; 37:46-50. [PMID: 26821363 DOI: 10.1016/j.gde.2015.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/21/2015] [Accepted: 12/24/2015] [Indexed: 11/20/2022]
Abstract
Long noncoding RNAs (lncRNAs) were discovered in eukaryotes more than 30 years ago [1]. Recent advances in genomics have led to the discovery that lncRNAs are transcribed pervasively across the genome [2(•),3,4,5(•)]. There are an increasing number of reports that identify lncRNAs whose expression is modulated during cell differentiation or in disease states. However, biological functions for the vast majority of them are yet to be determined. Here, we propose two ways to identify lncRNAs that have biological functions: to identify lncRNAs with dedicated preinitiation complexes (PICs), and to focus on those whose transcription is highly regulated.
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50
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Rege M, Subramanian V, Zhu C, Hsieh THS, Weiner A, Friedman N, Clauder-Münster S, Steinmetz LM, Rando OJ, Boyer LA, Peterson CL. Chromatin Dynamics and the RNA Exosome Function in Concert to Regulate Transcriptional Homeostasis. Cell Rep 2015; 13:1610-22. [PMID: 26586442 PMCID: PMC4662874 DOI: 10.1016/j.celrep.2015.10.030] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 09/02/2015] [Accepted: 10/09/2015] [Indexed: 12/12/2022] Open
Abstract
The histone variant H2A.Z is a hallmark of nucleosomes flanking promoters of protein-coding genes and is often found in nucleosomes that carry lysine 56-acetylated histone H3 (H3-K56Ac), a mark that promotes replication-independent nucleosome turnover. Here, we find that H3-K56Ac promotes RNA polymerase II occupancy at many protein-coding and noncoding loci, yet neither H3-K56Ac nor H2A.Z has a significant impact on steady-state mRNA levels in yeast. Instead, broad effects of H3-K56Ac or H2A.Z on RNA levels are revealed only in the absence of the nuclear RNA exosome. H2A.Z is also necessary for the expression of divergent, promoter-proximal non-coding RNAs (ncRNAs) in mouse embryonic stem cells. Finally, we show that H2A.Z functions with H3-K56Ac to facilitate formation of chromosome interaction domains (CIDs). Our study suggests that H2A.Z and H3-K56Ac work in concert with the RNA exosome to control mRNA and ncRNA expression, perhaps in part by regulating higher-order chromatin structures.
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Affiliation(s)
- Mayuri Rege
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Vidya Subramanian
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Chenchen Zhu
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg 69117, Germany
| | - Tsung-Han S Hsieh
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Assaf Weiner
- School of Computer Science and Engineering, The Hebrew University, Jerusalem 91904, Israel; Alexander Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Nir Friedman
- School of Computer Science and Engineering, The Hebrew University, Jerusalem 91904, Israel; Alexander Silberman Institute of Life Sciences, The Hebrew University, Jerusalem 91904, Israel
| | | | - Lars M Steinmetz
- Genome Biology Unit, European Molecular Biology Laboratory, Heidelberg 69117, Germany; Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Oliver J Rando
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Laurie A Boyer
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Craig L Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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