101
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Molecular basis for the interaction between Integrator subunits IntS9 and IntS11 and its functional importance. Proc Natl Acad Sci U S A 2017; 114:4394-4399. [PMID: 28396433 DOI: 10.1073/pnas.1616605114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The metazoan Integrator complex (INT) has important functions in the 3'-end processing of noncoding RNAs, including the uridine-rich small nuclear RNA (UsnRNA) and enhancer RNA (eRNA), and in the transcription of coding genes by RNA polymerase II. The INT contains at least 14 subunits, but its molecular mechanism of action is poorly understood, because currently there is little structural information about its subunits. The endonuclease activity of INT is mediated by its subunit 11 (IntS11), which belongs to the metallo-β-lactamase superfamily and is a paralog of CPSF-73, the endonuclease for pre-mRNA 3'-end processing. IntS11 forms a stable complex with Integrator complex subunit 9 (IntS9) through their C-terminal domains (CTDs). Here, we report the crystal structure of the IntS9-IntS11 CTD complex at 2.1-Å resolution and detailed, structure-based biochemical and functional studies. The complex is composed of a continuous nine-stranded β-sheet with four strands from IntS9 and five from IntS11. Highly conserved residues are located in the extensive interface between the two CTDs. Yeast two-hybrid assays and coimmunoprecipitation experiments confirm the structural observations on the complex. Functional studies demonstrate that the IntS9-IntS11 interaction is crucial for the role of INT in snRNA 3'-end processing.
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102
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Kheirallah AK, de Moor CH, Faiz A, Sayers I, Hall IP. Lung function associated gene Integrator Complex subunit 12 regulates protein synthesis pathways. BMC Genomics 2017; 18:248. [PMID: 28335732 PMCID: PMC5364626 DOI: 10.1186/s12864-017-3628-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 03/14/2017] [Indexed: 12/15/2022] Open
Abstract
Background Genetic studies of human lung function and Chronic Obstructive Pulmonary Disease have identified a highly significant and reproducible signal on 4q24. It remains unclear which of the two candidate genes within this locus may regulate lung function: GSTCD, a gene with unknown function, and/or INTS12, a member of the Integrator Complex which is currently thought to mediate 3’end processing of small nuclear RNAs. Results We found that, in lung tissue, 4q24 polymorphisms associated with lung function correlate with INTS12 but not neighbouring GSTCD expression. In contrast to the previous reports in other species, we only observed a minor alteration of snRNA processing following INTS12 depletion. RNAseq analysis of knockdown cells instead revealed dysregulation of a core subset of genes relevant to airway biology and a robust downregulation of protein synthesis pathways. Consistent with this, protein translation was decreased in INTS12 knockdown cells. In addition, ChIPseq experiments demonstrated INTS12 binding throughout the genome, which was enriched in transcriptionally active regions. Finally, we defined the INTS12 regulome which includes genes belonging to the protein synthesis pathways. Conclusion INTS12 has functions beyond the canonical snRNA processing. We show that it regulates translation by regulating the expression of genes belonging to protein synthesis pathways. This study provides a detailed analysis of INTS12 activities on a genome-wide scale and contributes to the biology behind the genetic association for lung function at 4q24. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3628-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexander K Kheirallah
- Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK. .,Division of Respiratory Medicine, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK.
| | - Cornelia H de Moor
- Division of Molecular and Cellular Sciences, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Alen Faiz
- Department of Pulmonology, University of Groningen, Groningen, 9713 GZ, Netherlands
| | - Ian Sayers
- Division of Respiratory Medicine, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Ian P Hall
- Division of Respiratory Medicine, School of Medicine, University of Nottingham, Nottingham, NG7 2UH, UK
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103
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Curina A, Termanini A, Barozzi I, Prosperini E, Simonatto M, Polletti S, Silvola A, Soldi M, Austenaa L, Bonaldi T, Ghisletti S, Natoli G. High constitutive activity of a broad panel of housekeeping and tissue-specific cis-regulatory elements depends on a subset of ETS proteins. Genes Dev 2017; 31:399-412. [PMID: 28275002 PMCID: PMC5358759 DOI: 10.1101/gad.293134.116] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/03/2017] [Indexed: 11/24/2022]
Abstract
Here, Curina et al. found that a subgroup of ETS family transcription factors (the ELF proteins) shows a strong bias in its genomic distribution by binding in very close proximity (<60 nt) to the transcription start sites of housekeeping genes. They show that a limited number of highly active transcription factors can equip cis-regulatory elements with disparate functional roles and cell type specificity with the ability to efficiently promote transcription. Enhancers and promoters that control the transcriptional output of terminally differentiated cells include cell type-specific and broadly active housekeeping elements. Whether the high constitutive activity of these two groups of cis-regulatory elements relies on entirely distinct or instead also on shared regulators is unknown. By dissecting the cis-regulatory repertoire of macrophages, we found that the ELF subfamily of ETS proteins selectively bound within 60 base pairs (bp) from the transcription start sites of highly active housekeeping genes. ELFs also bound constitutively active, but not poised, macrophage-specific enhancers and promoters. The role of ELFs in promoting high-level constitutive transcription was suggested by multiple evidence: ELF sites enabled robust transcriptional activation by endogenous and minimal synthetic promoters, ELF recruitment was stabilized by the transcriptional machinery, and ELF proteins mediated recruitment of transcriptional and chromatin regulators to core promoters. These data suggest that the co-optation of a limited number of highly active transcription factors represents a broadly adopted strategy to equip both cell type-specific and housekeeping cis-regulatory elements with the ability to efficiently promote transcription.
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Affiliation(s)
- Alessia Curina
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | | | - Iros Barozzi
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Elena Prosperini
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Marta Simonatto
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Sara Polletti
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Alessio Silvola
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Monica Soldi
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Liv Austenaa
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Tiziana Bonaldi
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy
| | - Serena Ghisletti
- Humanitas Clinical and Research Center, 20089 Rozzano-Milan, Italy
| | - Gioacchino Natoli
- Department of Experimental Oncology, European Institute of Oncology (IEO), 20139 Milan, Italy.,Humanitas University, 20089 Rozzano-Milan, Italy
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104
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Ssb1 and Ssb2 cooperate to regulate mouse hematopoietic stem and progenitor cells by resolving replicative stress. Blood 2017; 129:2479-2492. [PMID: 28270450 DOI: 10.1182/blood-2016-06-725093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 02/26/2017] [Indexed: 12/14/2022] Open
Abstract
Hematopoietic stem and progenitor cells (HSPCs) are vulnerable to endogenous damage and defects in DNA repair can limit their function. The 2 single-stranded DNA (ssDNA) binding proteins SSB1 and SSB2 are crucial regulators of the DNA damage response; however, their overlapping roles during normal physiology are incompletely understood. We generated mice in which both Ssb1 and Ssb2 were constitutively or conditionally deleted. Constitutive Ssb1/Ssb2 double knockout (DKO) caused early embryonic lethality, whereas conditional Ssb1/Ssb2 double knockout (cDKO) in adult mice resulted in acute lethality due to bone marrow failure and intestinal atrophy featuring stem and progenitor cell depletion, a phenotype unexpected from the previously reported single knockout models of Ssb1 or Ssb2 Mechanistically, cDKO HSPCs showed altered replication fork dynamics, massive accumulation of DNA damage, genome-wide double-strand breaks enriched at Ssb-binding regions and CpG islands, together with the accumulation of R-loops and cytosolic ssDNA. Transcriptional profiling of cDKO HSPCs revealed the activation of p53 and interferon (IFN) pathways, which enforced cell cycling in quiescent HSPCs, resulting in their apoptotic death. The rapid cell death phenotype was reproducible in in vitro cultured cDKO-hematopoietic stem cells, which were significantly rescued by nucleotide supplementation or after depletion of p53. Collectively, Ssb1 and Ssb2 control crucial aspects of HSPC function, including proliferation and survival in vivo by resolving replicative stress to maintain genomic stability.
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105
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van den Berg DLC, Azzarelli R, Oishi K, Martynoga B, Urbán N, Dekkers DHW, Demmers JA, Guillemot F. Nipbl Interacts with Zfp609 and the Integrator Complex to Regulate Cortical Neuron Migration. Neuron 2017; 93:348-361. [PMID: 28041881 PMCID: PMC5263256 DOI: 10.1016/j.neuron.2016.11.047] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 10/10/2016] [Accepted: 11/17/2016] [Indexed: 12/18/2022]
Abstract
Mutations in NIPBL are the most frequent cause of Cornelia de Lange syndrome (CdLS), a developmental disorder encompassing several neurological defects, including intellectual disability and seizures. How NIPBL mutations affect brain development is not understood. Here we identify Nipbl as a functional interaction partner of the neural transcription factor Zfp609 in brain development. Depletion of Zfp609 or Nipbl from cortical neural progenitors in vivo is detrimental to neuronal migration. Zfp609 and Nipbl overlap at genomic binding sites independently of cohesin and regulate genes that control cortical neuron migration. We find that Zfp609 and Nipbl interact with the Integrator complex, which functions in RNA polymerase 2 pause release. Indeed, Zfp609 and Nipbl co-localize at gene promoters containing paused RNA polymerase 2, and Integrator similarly regulates neuronal migration. Our data provide a rationale and mechanistic insights for the role of Nipbl in the neurological defects associated with CdLS.
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Affiliation(s)
| | - Roberta Azzarelli
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
| | - Koji Oishi
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
| | - Ben Martynoga
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
| | - Noelia Urbán
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
| | - Dick H W Dekkers
- Center for Proteomics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, the Netherlands
| | - Jeroen A Demmers
- Center for Proteomics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, the Netherlands
| | - François Guillemot
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK.
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106
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Abstract
Transcription occurring at gene loci results in accumulation of mature RNA molecules (i.e., mRNAs) that can be easily assayed by RT-PCR or RNA sequencing. However, the steady-state level of RNA does not accurately mirror transcriptional activity per se. In fact, RNA stability plays a major role in determining the relative abundance of any given RNA molecule. Here, I describe a protocol of Nuclear Run-On assay coupled to deep sequencing to assess real-time transcription from engaged RNA polymerase. Mapping nascent transcripts at the genome-wide scale provides a reliable measure of transcriptional activity in mammalian cells and delivers a high-resolution map of coding and noncoding transcripts that is especially useful for annotation and quantification of short-lived RNA molecules.
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107
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Targeting Chromatin Remodeling in Inflammation and Fibrosis. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 107:1-36. [PMID: 28215221 DOI: 10.1016/bs.apcsb.2016.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mucosal surfaces of the human body are lined by a contiguous epithelial cell surface that forms a barrier to aerosolized pathogens. Specialized pattern recognition receptors detect the presence of viral pathogens and initiate protective host responses by triggering activation of the nuclear factor κB (NFκB)/RelA transcription factor and formation of a complex with the positive transcription elongation factor (P-TEFb)/cyclin-dependent kinase (CDK)9 and Bromodomain-containing protein 4 (BRD4) epigenetic reader. The RelA·BRD4·P-TEFb complex produces acute inflammation by regulating transcriptional elongation, which produces a rapid genomic response by inactive genes maintained in an open chromatin configuration engaged with hypophosphorylated RNA polymerase II. We describe recent studies that have linked prolonged activation of the RelA-BRD4 pathway with the epithelial-mesenchymal transition (EMT) by inducing a core of EMT corepressors, stimulating secretion of growth factors promoting airway fibrosis. The mesenchymal state produces rewiring of the kinome and reprogramming of innate responses toward inflammation. In addition, the core regulator Zinc finger E-box homeodomain 1 (ZEB1) silences the expression of the interferon response factor 1 (IRF1), required for type III IFN expression. This epigenetic silencing is mediated by the Enhancer of Zeste 2 (EZH2) histone methyltransferase. Because of their potential applications in cancer and inflammation, small-molecule inhibitors of NFκB/RelA, CDK9, BRD4, and EZH2 have been the targets of medicinal chemistry efforts. We suggest that disruption of the RelA·BRD4·P-TEFb pathway and EZH2 methyltransferase has important implications for reversing fibrosis and restoring normal mucosal immunity in chronic inflammatory diseases.
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108
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Liu Y, Li S, Chen Y, Kimberlin AN, Cahoon EB, Yu B. snRNA 3' End Processing by a CPSF73-Containing Complex Essential for Development in Arabidopsis. PLoS Biol 2016; 14:e1002571. [PMID: 27780203 PMCID: PMC5079582 DOI: 10.1371/journal.pbio.1002571] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 09/26/2016] [Indexed: 01/26/2023] Open
Abstract
Uridine-rich small nuclear RNAs (snRNAs) are the basal components of the spliceosome and play essential roles in splicing. The biogenesis of the majority of snRNAs involves 3′ end endonucleolytic cleavage of the nascent transcript from the elongating DNA-dependent RNA ploymerase II. However, the protein factors responsible for this process remain elusive in plants. Here, we show that DEFECTIVE in snRNA PROCESSING 1 (DSP1) is an essential protein for snRNA 3′ end maturation in Arabidopsis. A hypomorphic dsp1-1 mutation causes pleiotropic developmental defects, impairs the 3′ end processing of snRNAs, increases the levels of snRNA primary transcripts (pre-snRNAs), and alters the occupancy of Pol II at snRNA loci. In addition, DSP1 binds snRNA loci and interacts with Pol-II in a DNA/RNA-dependent manner. We further show that DSP1 forms a conserved complex, which contains at least four additional proteins, to catalyze snRNA 3′ end maturation in Arabidopsis. The catalytic component of this complex is likely the cleavage and polyadenylation specificity factor 73 kDa-I (CSPF73-I), which is the nuclease cleaving the pre-mRNA 3′ end. However, the DSP1 complex does not affect pre-mRNA 3′ end cleavage, suggesting that plants may use different CPSF73-I-containing complexes to process snRNAs and pre-mRNAs. This study identifies a complex responsible for the snRNA 3′ end maturation in plants and uncovers a previously unknown function of CPSF73 in snRNA maturation. This study identifies a protein complex in plants that is responsible for the maturation of the 3′ ends of spliceosomal snRNAs and uncovers a novel function for the mRNA 3′ cleavage nuclease CPSF73. snRNAs form the RNA components of the spliceosome and are required for spliceosome formation and splicing. The generation of snRNAs involves 3′ end endonucleolytic cleavage of primary snRNA transcripts (pre-snRNAs). The factors responsible for pre-snRNA 3′ end cleavage are known in metazoans, but many of these components are missing in plants. Therefore, the proteins that catalyze pre-snRNA cleavage in plants and the mechanism leading to plant snRNA 3′ maturation are unknown. Here, we show that a DSP1 complex (containing DSP1, DSP2, DSP3, DSP4, and CPFS73-I) is responsible for pre-snRNA 3′ end cleavage in Arabidopsis. We further show that CPSF73-I, which is known to cleave the pre-mRNA 3′ end, is likely the enzyme also catalyzing snRNA 3′ end maturation in plants. Interestingly, plants appear to use two different CPSF73-I-containing complexes to catalyze the maturation of mRNAs and snRNAs. The study thereby identifies an snRNA-processing complex in plants and also elucidates a new role for CPSF73-I in this process.
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Affiliation(s)
- Yunfeng Liu
- Center for Plant Science Innovation and School of Biological Sciences, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Shengjun Li
- Center for Plant Science Innovation and School of Biological Sciences, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Yuan Chen
- Plant Gene Expression Center, US Department of Agriculture-Agricultural Research Service, University of California-Berkeley, Albany, California, United States of America
| | - Athen N. Kimberlin
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Edgar B. Cahoon
- Center for Plant Science Innovation and Department of Biochemistry, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Bin Yu
- Center for Plant Science Innovation and School of Biological Sciences, University of Nebraska, Lincoln, Nebraska, United States of America
- * E-mail:
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109
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Resto M, Kim BH, Fernandez AG, Abraham BJ, Zhao K, Lewis BA. O-GlcNAcase Is an RNA Polymerase II Elongation Factor Coupled to Pausing Factors SPT5 and TIF1β. J Biol Chem 2016; 291:22703-22713. [PMID: 27601472 DOI: 10.1074/jbc.m116.751420] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 08/29/2016] [Indexed: 12/24/2022] Open
Abstract
We describe here the identification and functional characterization of the enzyme O-GlcNAcase (OGA) as an RNA polymerase II elongation factor. Using in vitro transcription elongation assays, we show that OGA activity is required for elongation in a crude nuclear extract system, whereas in a purified system devoid of OGA the addition of rOGA inhibited elongation. Furthermore, OGA is physically associated with the known RNA polymerase II (pol II) pausing/elongation factors SPT5 and TRIM28-KAP1-TIF1β, and a purified OGA-SPT5-TIF1β complex has elongation properties. Lastly, ChIP-seq experiments show that OGA maps to the transcriptional start site/5' ends of genes, showing considerable overlap with RNA pol II, SPT5, TRIM28-KAP1-TIF1β, and O-GlcNAc itself. These data all point to OGA as a component of the RNA pol II elongation machinery regulating elongation genome-wide. Our results add a novel and unexpected dimension to the regulation of elongation by the insertion of O-GlcNAc cycling into the pol II elongation regulatory dynamics.
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Affiliation(s)
- Melissa Resto
- From the Transcriptional Regulation and Biochemistry Unit, Metabolism Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 30893
| | - Bong-Hyun Kim
- Frederick National Laboratory for Cancer Research, Leidos Biomedical Research, Inc., Frederick, Maryland 21702
| | - Alfonso G Fernandez
- From the Transcriptional Regulation and Biochemistry Unit, Metabolism Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 30893
| | - Brian J Abraham
- Bioinformatics Program, Boston University, Boston, Massachusetts 02215, and.,Laboratory of Epigenome Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Keji Zhao
- Laboratory of Epigenome Biology, NHLBI, National Institutes of Health, Bethesda, Maryland 20892
| | - Brian A Lewis
- From the Transcriptional Regulation and Biochemistry Unit, Metabolism Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 30893,
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110
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CRISPR-Cas9 mediated genetic engineering for the purification of the endogenous integrator complex from mammalian cells. Protein Expr Purif 2016; 128:101-8. [PMID: 27546450 DOI: 10.1016/j.pep.2016.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 08/12/2016] [Accepted: 08/16/2016] [Indexed: 01/14/2023]
Abstract
The Integrator Complex (INT) is a large multi-subunit protein complex, containing at least 14 subunits and a host of associated factors. These protein components have been established through pulldowns of overexpressed epitope tagged subunits or by using antibodies raised against specific subunits. Here, we utilize CRISPR/Cas9 gene editing technology to introduce N-terminal FLAG epitope tags into the endogenous genes that encode Integrator subunit 4 and 11 within HEK293T cells. We provide specific details regarding design, approaches for facile screening, and our observed frequency of successful recombination. Finally, using silver staining, Western blotting and LC-MS/MS we compare the components of INT of purifications from CRISPR derived lines to 293T cells overexpressing FLAG-INTS11 to define a highly resolved constituency of mammalian INT.
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111
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Sharma N. Regulation of RNA polymerase II-mediated transcriptional elongation: Implications in human disease. IUBMB Life 2016; 68:709-16. [DOI: 10.1002/iub.1538] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 07/14/2016] [Indexed: 01/03/2023]
Affiliation(s)
- Nimisha Sharma
- University School of Biotechnology, G.G.S. Indraprastha University; Dwarka New Delhi 110078 India
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112
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Vernimmen D, Bickmore WA. The Hierarchy of Transcriptional Activation: From Enhancer to Promoter. Trends Genet 2016; 31:696-708. [PMID: 26599498 DOI: 10.1016/j.tig.2015.10.004] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/18/2015] [Accepted: 10/15/2015] [Indexed: 12/20/2022]
Abstract
Regulatory elements (enhancers) that are remote from promoters play a critical role in the spatial, temporal, and physiological control of gene expression. Studies on specific loci, together with genome-wide approaches, suggest that there may be many common mechanisms involved in enhancer-promoter communication. Here, we discuss the multiprotein complexes that are recruited to enhancers and the hierarchy of events taking place between regulatory elements and promoters.
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Affiliation(s)
- Douglas Vernimmen
- The Roslin Institute, Developmental Biology Division, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK.
| | - Wendy A Bickmore
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
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113
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Rienzo M, Casamassimi A. Integrator complex and transcription regulation: Recent findings and pathophysiology. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1859:1269-80. [PMID: 27427483 DOI: 10.1016/j.bbagrm.2016.07.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 07/08/2016] [Accepted: 07/12/2016] [Indexed: 12/20/2022]
Abstract
In the last decade, a novel molecular complex has been added to the RNA polymerase II-mediated transcription machinery as one of the major components. This multiprotein complex, named Integrator, plays a pivotal role in the regulation of most RNA Polymerase II-dependent genes. This complex consists of at least 14 different subunits. However, studies investigating its structure and composition are still lacking. Although it was originally discovered as a complex implicated in the 3'-end formation of noncoding small nuclear RNAs, recent studies indicate additional roles for Integrator in transcription regulation, for example during transcription pause-release and elongation of polymerase, in the biogenesis of transcripts derived from enhancers, as well as in DNA and RNA metabolism for some of its components. Noteworthy, several subunits have been emerging to play roles during development and differentiation; more importantly, their alterations are likely to be involved in several human pathologies, including cancer and lung diseases.
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Affiliation(s)
- Monica Rienzo
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Via L. De Crecchio 7, 80138 Naples, Italy
| | - Amelia Casamassimi
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Via L. De Crecchio 7, 80138 Naples, Italy.
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114
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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: 86] [Impact Index Per Article: 10.8] [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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115
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Genome-wide association study identifies 8p21.3 associated with persistent hepatitis B virus infection among Chinese. Nat Commun 2016; 7:11664. [PMID: 27244555 PMCID: PMC4895015 DOI: 10.1038/ncomms11664] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 04/18/2016] [Indexed: 12/14/2022] Open
Abstract
Hepatitis B virus (HBV) infection is a common infectious disease. Here we perform a genome-wide association study (GWAS) among Chinese populations to identify novel genetic loci involved in persistent HBV infection. GWAS scan is performed in 1,251 persistently HBV infected subjects (PIs, cases) and 1,057 spontaneously recovered subjects (SRs, controls), followed by replications in four independent populations totally consisting of 3,905 PIs and 3,356 SRs. We identify a novel locus at 8p21.3 (index rs7000921, odds ratio=0.78, P=3.2 × 10−12). Furthermore, we identify significant expression quantitative trait locus associations for INTS10 gene at 8p21.3. We demonstrate that INST10 suppresses HBV replication via IRF3 in liver cells. In clinical plasma samples, we confirm that INST10 levels are significantly decreased in PIs compared with SRs, and negatively correlated with the HBV load. These findings highlight a novel antiviral gene INTS10 at 8p21.3 in the clearance of HBV infection. This genome-wide association study on persistent hepatitis B virus (HBV) infection among Chinese confirms previously associated genetic loci while discovering a novel protective locus at 8p21.3. The study also demonstrates the nearby gene INST10 suppresses HBV replication in vitro.
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Kragelund BB, Schenstrøm SM, Rebula CA, Panse VG, Hartmann-Petersen R. DSS1/Sem1, a Multifunctional and Intrinsically Disordered Protein. Trends Biochem Sci 2016; 41:446-459. [PMID: 26944332 DOI: 10.1016/j.tibs.2016.02.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/01/2016] [Accepted: 02/04/2016] [Indexed: 01/24/2023]
Abstract
DSS1/Sem1 is a versatile intrinsically disordered protein. Besides being a bona fide subunit of the 26S proteasome, DSS1 associates with other protein complexes, including BRCA2-RPA, involved in homologous recombination; the Csn12-Thp3 complex, involved in RNA splicing; the integrator, involved in transcription; and the TREX-2 complex, involved in nuclear export of mRNA and transcription elongation. As a subunit of the proteasome, DSS1 functions both in complex assembly and possibly as a ubiquitin receptor. Here, we summarise structural and functional aspects of DSS1/Sem1 with particular emphasis on its multifunctional and disordered properties. We suggest that DSS1/Sem1 can act as a polyanionic adhesive to prevent nonproductive interactions during construction of protein assemblies, uniquely employing different structures when associating with the diverse multisubunit complexes.
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Affiliation(s)
- Birthe B Kragelund
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Signe M Schenstrøm
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Caio A Rebula
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Vikram Govind Panse
- Institute of Biochemistry, Department of Biology, ETH Zürich, Zürich, Switzerland.
| | - Rasmus Hartmann-Petersen
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark.
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117
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Luo Z, Lin C. Enhancer, epigenetics, and human disease. Curr Opin Genet Dev 2016; 36:27-33. [DOI: 10.1016/j.gde.2016.03.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/24/2016] [Indexed: 02/09/2023]
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118
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Xie M, Zhang W, Shu MD, Xu A, Lenis DA, DiMaio D, Steitz JA. The host Integrator complex acts in transcription-independent maturation of herpesvirus microRNA 3' ends. Genes Dev 2015. [PMID: 26220997 PMCID: PMC4526738 DOI: 10.1101/gad.266973.115] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In this study, Xie et al. identify a novel Integrator cleavage step in a noncanonical microRNA (miRNA) biogenesis pathway. They found that this cleavage step occurs at the 3′ ends of HVS pre-miRNAs, which is regulated by a specific 3′ end processing signal, the miRNA 3′ box. The findings here provide further insight into the structure and function of the Integrator complex. Herpesvirus saimiri (HVS) is an oncogenic γ-herpesvirus that produces microRNAs (miRNAs) by cotranscription of precursor miRNA (pre-miRNA) hairpins immediately downstream from viral small nuclear RNAs (snRNA). The host cell Integrator complex, which recognizes the snRNA 3′ end processing signal (3′ box), generates the 5′ ends of HVS pre-miRNA hairpins. Here, we identify a novel 3′ box-like sequence (miRNA 3′ box) downstream from HVS pre-miRNAs that is essential for miRNA biogenesis. In vivo knockdown and rescue experiments confirmed that the 3′ end processing of HVS pre-miRNAs also depends on Integrator activity. Interaction between Integrator and HVS primary miRNA (pri-miRNA) substrates that contain only the miRNA 3′ box was confirmed by coimmunoprecipitation and an in situ proximity ligation assay (PLA) that we developed to localize specific transient RNA–protein interactions inside cells. Surprisingly, in contrast to snRNA 3′ end processing, HVS pre-miRNA 3′ end processing by Integrator can be uncoupled from transcription, enabling new approaches to study Integrator enzymology.
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Affiliation(s)
- Mingyi Xie
- Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA; Department of Molecular Biophysics and Biochemistry, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA
| | - Wei Zhang
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06510, USA
| | - Mei-Di Shu
- Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA; Department of Molecular Biophysics and Biochemistry, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA
| | - Acer Xu
- Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA; Department of Molecular Biophysics and Biochemistry, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA
| | - Diana A Lenis
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York 11794, USA
| | - Daniel DiMaio
- Department of Molecular Biophysics and Biochemistry, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA; Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06510, USA
| | - Joan A Steitz
- Howard Hughes Medical Institute, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA; Department of Molecular Biophysics and Biochemistry, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA
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119
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Lai F, Gardini A, Zhang A, Shiekhattar R. Integrator mediates the biogenesis of enhancer RNAs. Nature 2015; 525:399-403. [PMID: 26308897 PMCID: PMC4718573 DOI: 10.1038/nature14906] [Citation(s) in RCA: 203] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 07/07/2015] [Indexed: 01/03/2023]
Abstract
Integrator is a multi-subunit complex stably associated with the carboxy-terminal domain (CTD) of RNA polymerase II (RNAPII). Integrator is endowed with a core catalytic RNA endonuclease activity, which is required for the 3'-end processing of non-polyadenylated, RNAPII-dependent, uridylate-rich, small nuclear RNA genes. Here we examine the requirement of Integrator in the biogenesis of transcripts derived from distal regulatory elements (enhancers) involved in tissue- and temporal-specific regulation of gene expression in metazoans. Integrator is recruited to enhancers and super-enhancers in a stimulus-dependent manner. Functional depletion of Integrator subunits diminishes the signal-dependent induction of enhancer RNAs (eRNAs) and abrogates stimulus-induced enhancer-promoter chromatin looping. Global nuclear run-on and RNAPII profiling reveals a role for Integrator in 3'-end cleavage of eRNA primary transcripts leading to transcriptional termination. In the absence of Integrator, eRNAs remain bound to RNAPII and their primary transcripts accumulate. Notably, the induction of eRNAs and gene expression responsiveness requires the catalytic activity of Integrator complex. We propose a role for Integrator in biogenesis of eRNAs and enhancer function in metazoans.
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Affiliation(s)
- Fan Lai
- University of Miami Miller School of Medicine, Sylvester Comprehensive Cancer Center, Department of Human Genetics, Biomedical Research Building, Room 719, 1501 NW 10th Avenue, Miami, FL 33136
| | - Alessandro Gardini
- University of Miami Miller School of Medicine, Sylvester Comprehensive Cancer Center, Department of Human Genetics, Biomedical Research Building, Room 719, 1501 NW 10th Avenue, Miami, FL 33136
| | - Anda Zhang
- University of Miami Miller School of Medicine, Sylvester Comprehensive Cancer Center, Department of Human Genetics, Biomedical Research Building, Room 719, 1501 NW 10th Avenue, Miami, FL 33136
| | - Ramin Shiekhattar
- University of Miami Miller School of Medicine, Sylvester Comprehensive Cancer Center, Department of Human Genetics, Biomedical Research Building, Room 719, 1501 NW 10th Avenue, Miami, FL 33136
- To whom correspondence should be addressed, Phone: (305) 243-4579, Fax: (305) 243-6170,
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120
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Scheidegger A, Nechaev S. RNA polymerase II pausing as a context-dependent reader of the genome. Biochem Cell Biol 2015; 94:82-92. [PMID: 26555214 DOI: 10.1139/bcb-2015-0045] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The RNA polymerase II (Pol II) transcribes all mRNA genes in eukaryotes and is among the most highly regulated enzymes in the cell. The classic model of mRNA gene regulation involves recruitment of the RNA polymerase to gene promoters in response to environmental signals. Higher eukaryotes have an additional ability to generate multiple cell types. This extra level of regulation enables each cell to interpret the same genome by committing to one of the many possible transcription programs and executing it in a precise and robust manner. Whereas multiple mechanisms are implicated in cell type-specific transcriptional regulation, how one genome can give rise to distinct transcriptional programs and what mechanisms activate and maintain the appropriate program in each cell remains unclear. This review focuses on the process of promoter-proximal Pol II pausing during early transcription elongation as a key step in context-dependent interpretation of the metazoan genome. We highlight aspects of promoter-proximal Pol II pausing, including its interplay with epigenetic mechanisms, that may enable cell type-specific regulation, and emphasize some of the pertinent questions that remain unanswered and open for investigation.
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Affiliation(s)
- Adam Scheidegger
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58201, USA.,Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58201, USA
| | - Sergei Nechaev
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58201, USA.,Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58201, USA
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121
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Chen FX, Woodfin AR, Gardini A, Rickels RA, Marshall SA, Smith ER, Shiekhattar R, Shilatifard A. PAF1, a Molecular Regulator of Promoter-Proximal Pausing by RNA Polymerase II. Cell 2015; 162:1003-15. [PMID: 26279188 DOI: 10.1016/j.cell.2015.07.042] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/16/2015] [Accepted: 07/02/2015] [Indexed: 10/25/2022]
Abstract
The control of promoter-proximal pausing and the release of RNA polymerase II (Pol II) is a widely used mechanism for regulating gene expression in metazoans, especially for genes that respond to environmental and developmental cues. Here, we identify that Pol-II-associated factor 1 (PAF1) possesses an evolutionarily conserved function in metazoans in the regulation of promoter-proximal pausing. Reduction in PAF1 levels leads to an increased release of paused Pol II into gene bodies at thousands of genes. PAF1 depletion results in increased nascent and mature transcripts and increased levels of phosphorylation of Pol II's C-terminal domain on serine 2 (Ser2P). These changes can be explained by the recruitment of the Ser2P kinase super elongation complex (SEC) effecting increased release of paused Pol II into productive elongation, thus establishing PAF1 as a regulator of promoter-proximal pausing by Pol II.
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Affiliation(s)
- Fei Xavier Chen
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA
| | - Ashley R Woodfin
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA
| | - Alessandro Gardini
- Department of Human Genetics, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, 1501 NW 10(th) Avenue, Miami, FL 33136, USA
| | - Ryan A Rickels
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA
| | - Stacy A Marshall
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA
| | - Edwin R Smith
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA
| | - Ramin Shiekhattar
- Department of Human Genetics, Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, 1501 NW 10(th) Avenue, Miami, FL 33136, USA
| | - Ali Shilatifard
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, 320 E. Superior Street, Chicago, IL 60611, USA; Stowers Institute for Medical Research, 1000 East 50(th) Street, Kansas City, MO 64110, USA; Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, 320 E. Superior Street, Chicago, IL 60611, USA.
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122
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Latos PA, Goncalves A, Oxley D, Mohammed H, Turro E, Hemberger M. Fgf and Esrrb integrate epigenetic and transcriptional networks that regulate self-renewal of trophoblast stem cells. Nat Commun 2015. [PMID: 26206133 DOI: 10.1038/ncomms8776] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Esrrb (oestrogen-related receptor beta) is a transcription factor implicated in embryonic stem (ES) cell self-renewal, yet its knockout causes intrauterine lethality due to defects in trophoblast development. Here we show that in trophoblast stem (TS) cells, Esrrb is a downstream target of fibroblast growth factor (Fgf) signalling and is critical to drive TS cell self-renewal. In contrast to its occupancy of pluripotency-associated loci in ES cells, Esrrb sustains the stemness of TS cells by direct binding and regulation of TS cell-specific transcription factors including Elf5 and Eomes. To elucidate the mechanisms whereby Esrrb controls the expression of its targets, we characterized its TS cell-specific interactome using mass spectrometry. Unlike in ES cells, Esrrb interacts in TS cells with the histone demethylase Lsd1 and with the RNA Polymerase II-associated Integrator complex. Our findings provide new insights into both the general and context-dependent wiring of transcription factor networks in stem cells by master transcription factors.
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Affiliation(s)
- Paulina A Latos
- 1] Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK [2] Centre for Trophoblast Research, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
| | | | - David Oxley
- Proteomics Group, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Hisham Mohammed
- Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Ernest Turro
- 1] Department of Haematology, University of Cambridge, NHS Blood and Transplant, Long Road, Cambridge CB2 0PT, UK [2] Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, Robinson Way, Forvie Site, Cambridge CB2 0SR, UK
| | - Myriam Hemberger
- 1] Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK [2] Centre for Trophoblast Research, University of Cambridge, Downing Street, Cambridge CB2 3EG, UK
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123
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Baillat D, Wagner EJ. Integrator: surprisingly diverse functions in gene expression. Trends Biochem Sci 2015; 40:257-64. [PMID: 25882383 DOI: 10.1016/j.tibs.2015.03.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 03/07/2015] [Accepted: 03/09/2015] [Indexed: 01/06/2023]
Abstract
The discovery of the metazoan-specific Integrator (INT) complex represented a breakthrough in our understanding of noncoding U-rich small nuclear RNA (UsnRNA) maturation and has triggered a reevaluation of their biosynthesis mechanism. In the decade since, significant progress has been made in understanding the details of its recruitment, specificity, and assembly. While some discrepancies remain on how it interacts with the C-terminal domain (CTD) of the RNA polymerase II (RNAPII) and the details of its recruitment to UsnRNA genes, preliminary models have emerged. Recent provocative studies now implicate INT in the regulation of protein-coding gene transcription initiation and RNAPII pause-release, thereby broadening the scope of INT functions in gene expression regulation. We discuss the implications of these findings while putting them into the context of what is understood about INT function at UsnRNA genes.
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Affiliation(s)
- David Baillat
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, TX 77030, USA.
| | - Eric J Wagner
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School at Houston, Houston, TX 77030, USA; The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA.
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124
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Samarakkody A, Abbas A, Scheidegger A, Warns J, Nnoli O, Jokinen B, Zarns K, Kubat B, Dhasarathy A, Nechaev S. RNA polymerase II pausing can be retained or acquired during activation of genes involved in the epithelial to mesenchymal transition. Nucleic Acids Res 2015; 43:3938-49. [PMID: 25820424 PMCID: PMC4417172 DOI: 10.1093/nar/gkv263] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 03/17/2015] [Indexed: 12/26/2022] Open
Abstract
Promoter-proximal RNA polymerase II (Pol II) pausing is implicated in the regulation of gene transcription. However, the mechanisms of pausing including its dynamics during transcriptional responses remain to be fully understood. We performed global analysis of short capped RNAs and Pol II Chromatin Immunoprecipitation sequencing in MCF-7 breast cancer cells to map Pol II pausing across the genome, and used permanganate footprinting to specifically follow pausing during transcriptional activation of several genes involved in the epithelial to mesenchymal transition (EMT). We find that the gene for EMT master regulator Snail (SNAI1), but not Slug (SNAI2), shows evidence of Pol II pausing before activation. Transcriptional activation of the paused SNAI1 gene is accompanied by a further increase in Pol II pausing signal, whereas activation of non-paused SNAI2 gene results in the acquisition of a typical pausing signature. The increase in pausing signal reflects increased transcription initiation without changes in Pol II pausing. Activation of the heat shock HSP70 gene involves pausing release that speeds up Pol II turnover, but does not change pausing location. We suggest that Pol II pausing is retained during transcriptional activation and can further undergo regulated release in a signal-specific manner.
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Affiliation(s)
- Ann Samarakkody
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Ata Abbas
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Adam Scheidegger
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Jessica Warns
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Oscar Nnoli
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Bradley Jokinen
- Department of Computer Sciences, University of North Dakota, Grand Forks, ND 58202, USA
| | - Kris Zarns
- Department of Computer Sciences, University of North Dakota, Grand Forks, ND 58202, USA
| | - Brooke Kubat
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Archana Dhasarathy
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
| | - Sergei Nechaev
- Department of Basic Sciences, University of North Dakota School of Medicine, Grand Forks, ND 58202, USA
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125
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Chromatin proteomic profiling reveals novel proteins associated with histone-marked genomic regions. Proc Natl Acad Sci U S A 2015; 112:3841-6. [PMID: 25755260 DOI: 10.1073/pnas.1502971112] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
More than a thousand proteins are thought to contribute to mammalian chromatin and its regulation, but our understanding of the genomic occupancy and function of most of these proteins is limited. Here we describe an approach, which we call "chromatin proteomic profiling," to identify proteins associated with genomic regions marked by specifically modified histones. We used ChIP-MS to identify proteins associated with genomic regions marked by histones modified at specific lysine residues, including H3K27ac, H3K4me3, H3K79me2, H3K36me3, H3K9me3, and H4K20me3, in ES cells. We identified 332 known and 114 novel proteins associated with these histone-marked genomic segments. Many of the novel candidates have been implicated in various diseases, and their chromatin association may provide clues to disease mechanisms. More than 100 histone modifications have been described, so similar chromatin proteomic profiling studies should prove to be valuable for identifying many additional chromatin-associated proteins in a broad spectrum of cell types.
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126
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Getting up to speed with transcription elongation by RNA polymerase II. Nat Rev Mol Cell Biol 2015; 16:167-77. [PMID: 25693130 DOI: 10.1038/nrm3953] [Citation(s) in RCA: 565] [Impact Index Per Article: 62.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Recent advances in sequencing techniques that measure nascent transcripts and that reveal the positioning of RNA polymerase II (Pol II) have shown that the pausing of Pol II in promoter-proximal regions and its release to initiate a phase of productive elongation are key steps in transcription regulation. Moreover, after the release of Pol II from the promoter-proximal region, elongation rates are highly dynamic throughout the transcription of a gene, and vary on a gene-by-gene basis. Interestingly, Pol II elongation rates affect co-transcriptional processes such as splicing, termination and genome stability. Increasing numbers of factors and regulatory mechanisms have been associated with the steps of transcription elongation by Pol II, revealing that elongation is a highly complex process. Elongation is thus now recognized as a key phase in the regulation of transcription by Pol II.
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127
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Stadelmayer B, Micas G, Gamot A, Martin P, Malirat N, Koval S, Raffel R, Sobhian B, Severac D, Rialle S, Parrinello H, Cuvier O, Benkirane M. Integrator complex regulates NELF-mediated RNA polymerase II pause/release and processivity at coding genes. Nat Commun 2014; 5:5531. [PMID: 25410209 PMCID: PMC4263189 DOI: 10.1038/ncomms6531] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 10/10/2014] [Indexed: 12/19/2022] Open
Abstract
RNA polymerase II (RNAPII) pausing/termination shortly after initiation is a hallmark of gene regulation. Here, we show that negative elongation factor (NELF) interacts with Integrator complex subunits (INTScom), RNAPII and Spt5. The interaction between NELF and INTScom subunits is RNA and DNA independent. Using both human immunodeficiency virus type 1 promoter and genome-wide analyses, we demonstrate that Integrator subunits specifically control NELF-mediated RNAPII pause/release at coding genes. The strength of RNAPII pausing is determined by the nature of the NELF-associated INTScom subunits. Interestingly, in addition to controlling RNAPII pause-release INTS11 catalytic subunit of the INTScom is required for RNAPII processivity. Finally, INTScom target genes are enriched in human immunodeficiency virus type 1 transactivation response element/NELF binding element and in a 3' box sequence required for small nuclear RNA biogenesis. Revealing these unexpected functions of INTScom in regulating RNAPII pause-release and completion of mRNA synthesis of NELF-target genes will contribute to our understanding of the gene expression cycle. RNA polymerase II (RNAPII) pausing at transcriptional start sites is an important element of gene transcription regulation. Here, the authors implicate the Integrator complex as a regulator of RNAPII pause-release and completion of mRNA synthesis at a subset of the negative elongation factor target genes.
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Affiliation(s)
- Bernd Stadelmayer
- 1] Institute of Human Genetics, CNRS UPR1142, Laboratory of Molecular Virology; MGX-Montpellier GenomiX, 141 rue de la Cardonille, Montpellier 34396, France [2] LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France [3] INRA, TOXALIM (Research Centre in Food Toxicology), Toulouse 31300, France [4] IGF, MGX-Montpellier GenomiX, France
| | - Gaël Micas
- LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France
| | - Adrien Gamot
- LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France
| | - Pascal Martin
- 1] LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France [2] INRA, TOXALIM (Research Centre in Food Toxicology), Toulouse 31300, France
| | - Nathalie Malirat
- Institute of Human Genetics, CNRS UPR1142, Laboratory of Molecular Virology; MGX-Montpellier GenomiX, 141 rue de la Cardonille, Montpellier 34396, France
| | - Slavik Koval
- Institute of Human Genetics, CNRS UPR1142, Laboratory of Molecular Virology; MGX-Montpellier GenomiX, 141 rue de la Cardonille, Montpellier 34396, France
| | - Raoul Raffel
- LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France
| | - Bijan Sobhian
- Institute of Human Genetics, CNRS UPR1142, Laboratory of Molecular Virology; MGX-Montpellier GenomiX, 141 rue de la Cardonille, Montpellier 34396, France
| | | | | | | | - Olivier Cuvier
- 1] LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France [2] INRA, TOXALIM (Research Centre in Food Toxicology), Toulouse 31300, France [3] IGF, MGX-Montpellier GenomiX, France
| | - Monsef Benkirane
- 1] Institute of Human Genetics, CNRS UPR1142, Laboratory of Molecular Virology; MGX-Montpellier GenomiX, 141 rue de la Cardonille, Montpellier 34396, France [2] LBME-CNRS, Cell Cycle Chromatin Dynamics Laboratory. University Paul Sabatier, Toulouse 31061, France [3] INRA, TOXALIM (Research Centre in Food Toxicology), Toulouse 31300, France [4] IGF, MGX-Montpellier GenomiX, France
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