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Structural basis for transcription antitermination at bacterial intrinsic terminator. Nat Commun 2019; 10:3048. [PMID: 31296855 PMCID: PMC6624301 DOI: 10.1038/s41467-019-10955-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/29/2019] [Indexed: 01/25/2023] Open
Abstract
Bacteriophages typically hijack the host bacterial transcriptional machinery to regulate their own gene expression and that of the host bacteria. The structural basis for bacteriophage protein-mediated transcription regulation—in particular transcription antitermination—is largely unknown. Here we report the 3.4 Å and 4.0 Å cryo-EM structures of two bacterial transcription elongation complexes (P7-NusA-TEC and P7-TEC) comprising the bacteriophage protein P7, a master host-transcription regulator encoded by bacteriophage Xp10 of the rice pathogen Xanthomonas oryzae pv. Oryzae (Xoo) and discuss the mechanisms by which P7 modulates the host bacterial RNAP. The structures together with biochemical evidence demonstrate that P7 prevents transcription termination by plugging up the RNAP RNA-exit channel and impeding RNA-hairpin formation at the intrinsic terminator. Moreover, P7 inhibits transcription initiation by restraining RNAP-clamp motions. Our study reveals the structural basis for transcription antitermination by phage proteins and provides insights into bacterial transcription regulation. Bacteriophages reprogram the host transcriptional machinery. Here the authors provide insights into the mechanism of how bacteriophages regulate host transcription by determining the cryo-EM structures of two bacterial transcription elongation complexes bound with the bacteriophage master host-transcription regulator protein P7.
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2
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Brown DR, Sheppard CM, Burchell L, Matthews S, Wigneshweraraj S. The Xp10 Bacteriophage Protein P7 Inhibits Transcription by the Major and Major Variant Forms of the Host RNA Polymerase via a Common Mechanism. J Mol Biol 2016; 428:3911-3919. [PMID: 27515396 PMCID: PMC5053324 DOI: 10.1016/j.jmb.2016.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 01/24/2023]
Abstract
The σ factor is a functionally obligatory subunit of the bacterial transcription machinery, the RNA polymerase. Bacteriophage-encoded small proteins that either modulate or inhibit the bacterial RNAP to allow the temporal regulation of bacteriophage gene expression often target the activity of the major bacterial σ factor, σ70. Previously, we showed that during Xanthomonas oryzae phage Xp10 infection, the phage protein P7 inhibits the host RNAP by preventing the productive engagement with the promoter and simultaneously displaces the σ70 factor from the RNAP. In this study, we demonstrate that P7 also inhibits the productive engagement of the bacterial RNAP containing the major variant bacterial σ factor, σ54, with its cognate promoter. The results suggest for the first time that the major variant form of the host RNAP can also be targeted by bacteriophage-encoded transcription regulatory proteins. Since the major and major variant σ factor interacting surfaces in the RNAP substantially overlap, but different regions of σ70 and σ54 are used for binding to the RNAP, our results further underscore the importance of the σ–RNAP interface in bacterial RNAP function and regulation and potentially for intervention by antibacterials. Xp10 phage transcription regulator P7 inhibits transcription by RNAP containing σ54. P7 prevents the productive engagement of the σ54–RNAP with the promoter DNA. • P7 disrupts preformed σ54–RNAP-promoter complexes.
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Affiliation(s)
- D R Brown
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK.
| | - C M Sheppard
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - L Burchell
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - S Matthews
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK
| | - S Wigneshweraraj
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, SW7 2AZ, UK.
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3
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Yang H, Ma Y, Wang Y, Yang H, Shen W, Chen X. Transcription regulation mechanisms of bacteriophages: recent advances and future prospects. Bioengineered 2015; 5:300-4. [PMID: 25482231 DOI: 10.4161/bioe.32110] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Phage diversity significantly contributes to ecology and evolution of new bacterial species through horizontal gene transfer. Therefore, it is essential to understand the mechanisms underlying phage-host interactions. After initial infection, the phage utilizes the transcriptional machinery of the host to direct the expression of its own genes. This review presents a view on the transcriptional regulation mechanisms of bacteriophages, and its contribution to phage diversity and classification. Through this review, we aim to broaden the understanding of phage-host interactions while providing a reference source for researchers studying the regulation of phage transcription.
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Affiliation(s)
- Haiquan Yang
- a Key Laboratory of Industrial Biotechnology; Ministry of Education; School of Biotechnology; Jiangnan University; Wuxi, China
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Volante A, Carrasco B, Tabone M, Alonso JC. The interaction of ω2 with the RNA polymerase β' subunit functions as an activation to repression switch. Nucleic Acids Res 2015; 43:9249-61. [PMID: 26243774 PMCID: PMC4627068 DOI: 10.1093/nar/gkv788] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 07/23/2015] [Indexed: 12/03/2022] Open
Abstract
The ω gene is encoded in broad-host range and low-copy plasmids. It is genetically linked to antibiotic resistance genes of the major human pathogens of phylum Firmicutes. The homodimeric forms of ω (ω2) coordinate the plasmid copy number control, faithful partition (ω2 and δ2) and better-than-random segregation (ζϵ2ζ) systems. The promoter (P) of the ωϵζ operon (Pω) transiently interacts with ω2. Adding δ2 facilitates the formation of stable ω2·Pω complexes. Here we show that limiting ω2 interacts with the N-terminal domain of the β’ subunit of the Bacillus subtilis RNA polymerase (RNAP-σA) vegetative holoenzyme. In this way ω2 recruits RNAP-σA onto Pω DNA. Partial Pω occupancy by ω2 increases the rate at which RNAP-σA complex shifts from its closed (RPC) to open (RPO) form. This shift increases transcription activation. Adding δ2 further increases the rate of Pω transcription initiation, perhaps by stabilizing the ω2·Pω complex. In contrast, full operator occupancy by ω2 facilitates RPC formation, but it blocks RPO isomerization and represses Pω utilization. The stimulation and inhibition of RPO formation is the mechanism whereby ω2 mediates copy number fluctuation and stable plasmid segregation. By this mechanism, ω2 also indirectly influences the acquisition of antibiotic resistance genes.
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Affiliation(s)
- Andrea Volante
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, CNB-CSIC, 3, Darwin Street, 28049 Madrid, Spain
| | - Begoña Carrasco
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, CNB-CSIC, 3, Darwin Street, 28049 Madrid, Spain
| | - Mariangela Tabone
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, CNB-CSIC, 3, Darwin Street, 28049 Madrid, Spain
| | - Juan C Alonso
- Department of Microbial Biotechnology, Centro Nacional de Biotecnología, CNB-CSIC, 3, Darwin Street, 28049 Madrid, Spain
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Zenkin N, Severinov K, Yuzenkova Y. Bacteriophage Xp10 anti-termination factor p7 induces forward translocation by host RNA polymerase. Nucleic Acids Res 2015; 43:6299-308. [PMID: 26038312 PMCID: PMC4513864 DOI: 10.1093/nar/gkv586] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 05/05/2015] [Accepted: 05/22/2015] [Indexed: 11/12/2022] Open
Abstract
Regulation of transcription elongation is based on response of RNA polymerase (RNAP) to various pause signals and is modulated by various accessory factors. Here we report that a 7 kDa protein p7 encoded by bacteriophage Xp10 acts as an elongation processivity factor of RNAP of host bacterium Xanthomonas oryzae, a major rice pathogen. Our data suggest that p7 stabilizes the upstream DNA duplex of the elongation complex thus disfavouring backtracking and promoting forward translocated states of the elongation complex. The p7-induced 'pushing' of RNAP and modification of RNAP contacts with the upstream edge of the transcription bubble lead to read-through of various types of pauses and termination signals and generally increase transcription processivity and elongation rate, contributing for transcription of an extremely long late genes operon of Xp10. Forward translocation was observed earlier upon the binding of unrelated bacterial elongation factor NusG, suggesting that this may be a general pathway of regulation of transcription elongation.
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Affiliation(s)
- Nikolay Zenkin
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
| | - Konstantin Severinov
- Waksman Institute, Rutgers, the State University of New Jersey, Piscataway, NJ, 08854-8020, USA Skolkovo Institute of Science and Technology, Skolkovo,143025, Russia Institute of Molecular Genetics, Russian Academy of Sciences, Moscow,123182, Russia Institute of Gene Biology, Russian Academy of Sciences, Moscow, 119334, Russia
| | - Yulia Yuzenkova
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Baddiley-Clark Building, Richardson Road, Newcastle upon Tyne, NE2 4AX, UK
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Distinct pathways of RNA polymerase regulation by a phage-encoded factor. Proc Natl Acad Sci U S A 2015; 112:2017-22. [PMID: 25646468 DOI: 10.1073/pnas.1416330112] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Transcription antitermination is a common strategy of gene expression regulation, but only a few transcription antitermination factors have been studied in detail. Here, we dissect the transcription antitermination mechanism of Xanthomonas oryzae virus Xp10 protein p7, which binds host RNA polymerase (RNAP) and regulates both transcription initiation and termination. We show that p7 suppresses intrinsic termination by decreasing RNAP pausing and increasing the transcription complex stability, in cooperation with host-encoded factor NusA. Uniquely, the antitermination activity of p7 depends on the ω subunit of the RNAP core and is modulated by ppGpp. In contrast, the inhibition of transcription initiation by p7 does not require ω but depends on other RNAP sites. Our results suggest that p7, a bifunctional transcription factor, uses distinct mechanisms to control different steps of transcription. We propose that regulatory functions of the ω subunit revealed by our analysis may extend to its homologs in eukaryotic RNAPs.
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Liu B, Shadrin A, Sheppard C, Mekler V, Xu Y, Severinov K, Matthews S, Wigneshweraraj S. The sabotage of the bacterial transcription machinery by a small bacteriophage protein. BACTERIOPHAGE 2014; 4:e28520. [PMID: 24701369 DOI: 10.4161/bact.28520] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/11/2014] [Accepted: 03/12/2014] [Indexed: 11/19/2022]
Abstract
Many bacteriophages produce small proteins that specifically interfere with the bacterial host transcription machinery and thus contribute to the acquisition of the bacterial cell by the bacteriophage. We recently described how a small protein, called P7, produced by the Xp10 bacteriophage inhibits bacterial transcription initiation by causing the dissociation of the promoter specificity sigma factor subunit from the host RNA polymerase holoenzyme. In this addendum to the original publication, we present the highlights of that research.
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Affiliation(s)
- Bing Liu
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Andrey Shadrin
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Carol Sheppard
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Vladimir Mekler
- Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry; Rutgers, The State University of New Jersey; Piscataway, NJ USA
| | - Yingqi Xu
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
| | - Konstantin Severinov
- Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry; Rutgers, The State University of New Jersey; Piscataway, NJ USA ; St. Petersburg State Polytechnical University; St. Petersburg, Russia
| | - Steve Matthews
- MRC Centre for Molecular Bacteriology and Infection; Imperial College London; London, UK
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Liu B, Shadrin A, Sheppard C, Mekler V, Xu Y, Severinov K, Matthews S, Wigneshweraraj S. A bacteriophage transcription regulator inhibits bacterial transcription initiation by σ-factor displacement. Nucleic Acids Res 2014; 42:4294-305. [PMID: 24482445 PMCID: PMC3985653 DOI: 10.1093/nar/gku080] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bacteriophages (phages) appropriate essential processes of bacterial hosts to benefit their own development. The multisubunit bacterial RNA polymerase (RNAp) enzyme, which catalyses DNA transcription, is targeted by phage-encoded transcription regulators that selectively modulate its activity. Here, we describe the structural and mechanistic basis for the inhibition of bacterial RNAp by the transcription regulator P7 encoded by Xanthomonas oryzae phage Xp10. We reveal that P7 uses a two-step mechanism to simultaneously interact with the catalytic β and β' subunits of the bacterial RNAp and inhibits transcription initiation by inducing the displacement of the σ(70)-factor on initial engagement of RNAp with promoter DNA. The new mode of interaction with and inhibition mechanism of bacterial RNAp by P7 underscore the remarkable variety of mechanisms evolved by phages to interfere with host transcription.
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Affiliation(s)
- Bing Liu
- MRC Centre for Molecular Microbiology and Infection, Imperial College London, London SW7 2AZ, UK, Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway, NJ USA and St. Petersburg State Polytechnical University, St. Petersburg, Russia
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Drulis-Kawa Z, Majkowska-Skrobek G, Maciejewska B, Delattre AS, Lavigne R. Learning from bacteriophages - advantages and limitations of phage and phage-encoded protein applications. Curr Protein Pept Sci 2012; 13:699-722. [PMID: 23305359 PMCID: PMC3594737 DOI: 10.2174/138920312804871193] [Citation(s) in RCA: 161] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 07/12/2012] [Accepted: 09/20/2012] [Indexed: 12/18/2022]
Abstract
The emergence of bacteria resistance to most of the currently available antibiotics has become a critical therapeutic problem. The bacteria causing both hospital and community-acquired infections are most often multidrug resistant. In view of the alarming level of antibiotic resistance between bacterial species and difficulties with treatment, alternative or supportive antibacterial cure has to be developed. The presented review focuses on the major characteristics of bacteriophages and phage-encoded proteins affecting their usefulness as antimicrobial agents. We discuss several issues such as mode of action, pharmacodynamics, pharmacokinetics, resistance and manufacturing aspects of bacteriophages and phage-encoded proteins application.
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Affiliation(s)
- Zuzanna Drulis-Kawa
- Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland.
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10
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Berdygulova Z, Esyunina D, Miropolskaya N, Mukhamedyarov D, Kuznedelov K, Nickels BE, Severinov K, Kulbachinskiy A, Minakhin L. A novel phage-encoded transcription antiterminator acts by suppressing bacterial RNA polymerase pausing. Nucleic Acids Res 2012; 40:4052-63. [PMID: 22238378 PMCID: PMC3351154 DOI: 10.1093/nar/gkr1285] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Gp39, a small protein encoded by Thermus thermophilus phage P23–45, specifically binds the host RNA polymerase (RNAP) and inhibits transcription initiation. Here, we demonstrate that gp39 also acts as an antiterminator during transcription through intrinsic terminators. The antitermination activity of gp39 relies on its ability to suppress transcription pausing at poly(U) tracks. Gp39 also accelerates transcription elongation by decreasing RNAP pausing and backtracking but does not significantly affect the rates of catalysis of individual reactions in the RNAP active center. We mapped the RNAP-gp39 interaction site to the β flap, a domain that forms a part of the RNA exit channel and is also a likely target for λ phage antiterminator proteins Q and N, and for bacterial elongation factor NusA. However, in contrast to Q and N, gp39 does not depend on NusA or other auxiliary factors for its activity. To our knowledge, gp39 is the first characterized phage-encoded transcription factor that affects every step of the transcription cycle and suppresses transcription termination through its antipausing activity.
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11
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Santangelo TJ, Artsimovitch I. Termination and antitermination: RNA polymerase runs a stop sign. Nat Rev Microbiol 2011; 9:319-29. [PMID: 21478900 DOI: 10.1038/nrmicro2560] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Termination signals induce rapid and irreversible dissociation of the nascent transcript from RNA polymerase. Terminators at the end of genes prevent unintended transcription into the downstream genes, whereas terminators in the upstream regulatory leader regions adjust expression of the structural genes in response to metabolic and environmental signals. Premature termination within an operon leads to potentially deleterious defects in the expression of the downstream genes, but also provides an important surveillance mechanism. This Review discusses the actions of bacterial and phage antiterminators that allow RNA polymerase to override a terminator when the circumstances demand it.
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Affiliation(s)
- Thomas J Santangelo
- Department of Microbiology and The RNA Group, The Ohio State University, Columbus, Ohio 43210, USA
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12
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Roucourt B, Lavigne R. The role of interactions between phage and bacterial proteins within the infected cell: a diverse and puzzling interactome. Environ Microbiol 2009; 11:2789-805. [PMID: 19691505 DOI: 10.1111/j.1462-2920.2009.02029.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Interactions between bacteriophage proteins and bacterial proteins are important for efficient infection of the host cell. The phage proteins involved in these bacteriophage-host interactions are often produced immediately after infection. A survey of the available set of published bacteriophage-host interactions reveals the targeted host proteins are inhibited, activated or functionally redirected by the phage protein. These interactions protect the bacteriophage from bacterial defence mechanisms or adapt the host-cell metabolism to establish an efficient infection cycle. Regrettably, a large majority of bacteriophage early proteins lack any identified function. Recent research into the antibacterial potential of bacteriophage-host interactions indicates that phage early proteins seem to target a wide variety of processes in the host cell - many of them non-essential. Since a clear understanding of such interactions may become important for regulations involving phage therapy and in biotechnological applications, increased scientific emphasis on the biological elucidation of such proteins is warranted.
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Affiliation(s)
- Bart Roucourt
- Division of Gene Technology, Department of Biosystems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 box 2462, B-3001 Leuven, Belgium
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Komissarova N, Velikodvorskaya T, Sen R, King RA, Banik-Maiti S, Weisberg RA. Inhibition of a transcriptional pause by RNA anchoring to RNA polymerase. Mol Cell 2008; 31:683-94. [PMID: 18775328 DOI: 10.1016/j.molcel.2008.06.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 04/04/2008] [Accepted: 06/18/2008] [Indexed: 11/18/2022]
Abstract
We describe a mechanism by which nascent RNA inhibits transcriptional pausing. PutL RNA of bacteriophage HK022 suppresses transcription termination at downstream terminators and pausing within a nearby U-rich sequence. In vitro transcription and footprinting assays reveal that this pausing results from backtracking of RNA polymerase and that binding of nascent putL RNA to polymerase limits backtracking by restricting re-entry of the transcript into the RNA exit channel. The restriction is local and relaxes as the transcript elongates. Our results suggest that putL RNA binds to the surface of polymerase close to the RNA exit channel, a region that includes amino acid residues important for antitermination. Although binding is essential for antipausing and antitermination, these two activities of put differ: antipausing is limited to the immediate vicinity of the putL site, but antitermination is not. We propose that RNA anchoring to the elongation complex is a widespread mechanism of pause regulation.
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Affiliation(s)
- Natalia Komissarova
- Section on Microbial Genetics, Laboratory of Molecular Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6 Center Drive, Bethesda, MD 20892-2785, USA
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14
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Nechaev S, Severinov K. The elusive object of desire--interactions of bacteriophages and their hosts. Curr Opin Microbiol 2008; 11:186-93. [PMID: 18400552 DOI: 10.1016/j.mib.2008.02.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 02/18/2008] [Accepted: 02/21/2008] [Indexed: 12/27/2022]
Abstract
Bacteria and their viruses (phages) are locked in an evolutionary contest, with each side producing constantly changing mechanisms of attack and defense that are aimed to increase the odds of survival. As a result, phages play central roles in a great variety of genetic processes and increase the rate of evolutionary change of the bacterial host, which could ultimately work to the benefit of the host in a long run.
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Affiliation(s)
- Sergei Nechaev
- Laboratory of Molecular Carcinogenesis, NIEHS/NIH, Room D434, 111 Alexander Dr, Research Triangle Park, NC 27709, USA.
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