1
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Jain I, Kolesnik M, Kuznedelov K, Minakhin L, Morozova N, Shiriaeva A, Kirillov A, Medvedeva S, Livenskyi A, Kazieva L, Makarova KS, Koonin EV, Borukhov S, Severinov K, Semenova E. tRNA anticodon cleavage by target-activated CRISPR-Cas13a effector. Sci Adv 2024; 10:eadl0164. [PMID: 38657076 PMCID: PMC11042736 DOI: 10.1126/sciadv.adl0164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 03/20/2024] [Indexed: 04/26/2024]
Abstract
Type VI CRISPR-Cas systems are among the few CRISPR varieties that target exclusively RNA. The CRISPR RNA-guided, sequence-specific binding of target RNAs, such as phage transcripts, activates the type VI effector, Cas13. Once activated, Cas13 causes collateral RNA cleavage, which induces bacterial cell dormancy, thus protecting the host population from the phage spread. We show here that the principal form of collateral RNA degradation elicited by Leptotrichia shahii Cas13a expressed in Escherichia coli cells is the cleavage of anticodons in a subset of transfer RNAs (tRNAs) with uridine-rich anticodons. This tRNA cleavage is accompanied by inhibition of protein synthesis, thus providing defense from the phages. In addition, Cas13a-mediated tRNA cleavage indirectly activates the RNases of bacterial toxin-antitoxin modules cleaving messenger RNA, which could provide a backup defense. The mechanism of Cas13a-induced antiphage defense resembles that of bacterial anticodon nucleases, which is compatible with the hypothesis that type VI effectors evolved from an abortive infection module encompassing an anticodon nuclease.
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Affiliation(s)
- Ishita Jain
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Matvey Kolesnik
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Konstantin Kuznedelov
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Leonid Minakhin
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Natalia Morozova
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Anna Shiriaeva
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
- Saint Petersburg State University, Saint Petersburg, Russia
| | - Alexandr Kirillov
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Sofia Medvedeva
- Center for Molecular and Cellular Biology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Alexei Livenskyi
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | | | - Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health; Bethesda, MD, USA
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health; Bethesda, MD, USA
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine at Stratford; Stratford, NJ, USA
| | - Konstantin Severinov
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Moscow, Russia
| | - Ekaterina Semenova
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
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2
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Chaban A, Minakhin L, Goldobina E, Bae B, Hao Y, Borukhov S, Putzeys L, Boon M, Kabinger F, Lavigne R, Makarova KS, Koonin EV, Nair SK, Tagami S, Severinov K, Sokolova ML. Tail-tape-fused virion and non-virion RNA polymerases of a thermophilic virus with an extremely long tail. Nat Commun 2024; 15:317. [PMID: 38182597 PMCID: PMC10770324 DOI: 10.1038/s41467-023-44630-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 12/19/2023] [Indexed: 01/07/2024] Open
Abstract
Thermus thermophilus bacteriophage P23-45 encodes a giant 5,002-residue tail tape measure protein (TMP) that defines the length of its extraordinarily long tail. Here, we show that the N-terminal portion of P23-45 TMP is an unusual RNA polymerase (RNAP) homologous to cellular RNAPs. The TMP-fused virion RNAP transcribes pre-early phage genes, including a gene that encodes another, non-virion RNAP, that transcribes early and some middle phage genes. We report the crystal structures of both P23-45 RNAPs. The non-virion RNAP has a crab-claw-like architecture. By contrast, the virion RNAP adopts a unique flat structure without a clamp. Structure and sequence comparisons of the P23-45 RNAPs with other RNAPs suggest that, despite the extensive functional differences, the two P23-45 RNAPs originate from an ancient gene duplication in an ancestral phage. Our findings demonstrate striking adaptability of RNAPs that can be attained within a single virus species.
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Affiliation(s)
- Anastasiia Chaban
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205, Russia
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, 69117, Germany
| | - Leonid Minakhin
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, 19107, USA
| | - Ekaterina Goldobina
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205, Russia
- APC Microbiome Ireland, University College Cork, Cork, T12 YT20, Ireland
| | - Brain Bae
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yue Hao
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine at Stratford, Stratford, NJ, 08084-1489, USA
| | - Leena Putzeys
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven, 3001, Belgium
| | - Maarten Boon
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven, 3001, Belgium
| | - Florian Kabinger
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, 37077, Germany
| | - Rob Lavigne
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven, 3001, Belgium
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Satish K Nair
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Shunsuke Tagami
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan.
| | - Konstantin Severinov
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, 08854, USA.
- Institute of Molecular Genetics National Kurchatov Center, Moscow, 123182, Russia.
| | - Maria L Sokolova
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205, Russia.
- Department of Molecular Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, 37077, Germany.
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3
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Arseniev A, Panfilov M, Pobegalov G, Potyseva A, Pavlinova P, Yakunina M, Lee J, Borukhov S, Severinov K, Khodorkovskii M. Single-molecule studies reveal the off-pathway elemental pause state as a target of streptolydigin inhibition of RNA polymerase and its dramatic enhancement by Gre factors. bioRxiv 2023:2023.06.05.542125. [PMID: 37333075 PMCID: PMC10274647 DOI: 10.1101/2023.06.05.542125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Antibiotic streptolydigin (Stl) inhibits bacterial transcription by blocking the trigger loop folding in the active center of RNA polymerase (RNAP), which is essential for catalysis. We use acoustic force spectroscopy to characterize the dynamics of transcription elongation in ternary elongation complexes of RNAP (ECs) in the presence of Stl at a single-molecule level. We found that Stl induces long-lived stochastic pauses while the instantaneous velocity of transcription between the pauses is unaffected. Stl enhances the short-lived pauses associated with an off-pathway elemental paused state of the RNAP nucleotide addition cycle. Unexpectedly, we found that transcript cleavage factors GreA and GreB, which were thought to be Stl competitors, do not alleviate the streptolydigin-induced pausing; instead, they synergistically increase transcription inhibition by Stl. This is the first known instance of a transcriptional factor enhancing antibiotic activity. We propose a structural model of the EC-Gre-Stl complex that explains the observed Stl activities and provides insight into possible cooperative action of secondary channel factors and other antibiotics binding at the Stl-pocket. These results offer a new strategy for high-throughput screening for prospective antibacterial agents.
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Affiliation(s)
- Anatolii Arseniev
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russian Federation
| | - Mikhail Panfilov
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Georgii Pobegalov
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Alina Potyseva
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Polina Pavlinova
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Maria Yakunina
- Peter the Great St. Petersburg Polytechnic University, Saint Petersburg, Russia
| | - Jookyung Lee
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1489, USA
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1489, USA
| | - Konstantin Severinov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, United States
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4
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Fraser A, Sokolova ML, Drobysheva AV, Gordeeva JV, Borukhov S, Jumper J, Severinov KV, Leiman PG. Structural basis of template strand deoxyuridine promoter recognition by a viral RNA polymerase. Nat Commun 2022; 13:3526. [PMID: 35725571 PMCID: PMC9209446 DOI: 10.1038/s41467-022-31214-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 06/07/2022] [Indexed: 11/23/2022] Open
Abstract
Recognition of promoters in bacterial RNA polymerases (RNAPs) is controlled by sigma subunits. The key sequence motif recognized by the sigma, the -10 promoter element, is located in the non-template strand of the double-stranded DNA molecule ~10 nucleotides upstream of the transcription start site. Here, we explain the mechanism by which the phage AR9 non-virion RNAP (nvRNAP), a bacterial RNAP homolog, recognizes the -10 element of its deoxyuridine-containing promoter in the template strand. The AR9 sigma-like subunit, the nvRNAP enzyme core, and the template strand together form two nucleotide base-accepting pockets whose shapes dictate the requirement for the conserved deoxyuridines. A single amino acid substitution in the AR9 sigma-like subunit allows one of these pockets to accept a thymine thus expanding the promoter consensus. Our work demonstrates the extent to which viruses can evolve host-derived multisubunit enzymes to make transcription of their own genes independent of the host.
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Affiliation(s)
- Alec Fraser
- grid.176731.50000 0001 1547 9964Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-0647 USA
| | - Maria L. Sokolova
- grid.176731.50000 0001 1547 9964Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-0647 USA ,grid.454320.40000 0004 0555 3608Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - Arina V. Drobysheva
- grid.454320.40000 0004 0555 3608Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - Julia V. Gordeeva
- grid.454320.40000 0004 0555 3608Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia
| | - Sergei Borukhov
- grid.262671.60000 0000 8828 4546Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine at Stratford, Stratford, NJ 08084-1489 USA
| | - John Jumper
- grid.498210.60000 0004 5999 1726DeepMind Technologies Limited, London, UK
| | - Konstantin V. Severinov
- grid.454320.40000 0004 0555 3608Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, 121205 Russia ,grid.4886.20000 0001 2192 9124Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182 Russia ,grid.430387.b0000 0004 1936 8796Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 USA
| | - Petr G. Leiman
- grid.176731.50000 0001 1547 9964Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555-0647 USA
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5
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Bikmetov D, Hall AMJ, Livenskyi A, Gollan B, Ovchinnikov S, Gilep K, Kim J, Larrouy-Maumus G, Zgoda V, Borukhov S, Severinov K, Helaine S, Dubiley S. GNAT toxins evolve toward narrow tRNA target specificities. Nucleic Acids Res 2022; 50:5807-5817. [PMID: 35609997 PMCID: PMC9177977 DOI: 10.1093/nar/gkac356] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/10/2022] [Accepted: 05/05/2022] [Indexed: 12/16/2022] Open
Abstract
Type II toxin–antitoxin (TA) systems are two-gene modules widely distributed among prokaryotes. GNAT toxins associated with the DUF1778 antitoxins represent a large family of type II TAs. GNAT toxins inhibit cell growth by disrupting translation via acetylation of aminoacyl-tRNAs. In this work, we explored the evolutionary trajectory of GNAT toxins. Using LC/MS detection of acetylated aminoacyl-tRNAs combined with ribosome profiling, we systematically investigated the in vivo substrate specificity of an array of diverse GNAT toxins. Our functional data show that the majority of GNAT toxins are specific to Gly-tRNA isoacceptors. However, the phylogenetic analysis shows that the ancestor of GNAT toxins was likely a relaxed specificity enzyme capable of acetylating multiple elongator tRNAs. Together, our data provide a remarkable snapshot of the evolution of substrate specificity.
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Affiliation(s)
| | | | - Alexei Livenskyi
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Bridget Gollan
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Stepan Ovchinnikov
- Center for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia
| | - Konstantin Gilep
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow 119334, Russia
| | - Jenny Y Kim
- Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA
| | - Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK
| | - Viktor Zgoda
- Institute of Biomedical Chemistry, Moscow 119435, Russia
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1489, USA
| | | | | | - Svetlana Dubiley
- To whom correspondence should be addressed. Tel: +7 499 135 6089;
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6
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Chung S, Alhadid Y, Segal M, Lee J, Borukhov S, Weiss S. Single molecule activity assay for SARS-CoV-2 RNA dependent RNA polymerase. Biophys J 2022. [PMCID: PMC8833024 DOI: 10.1016/j.bpj.2021.11.954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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7
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Drobysheva AV, Panafidina SA, Kolesnik MV, Klimuk EI, Minakhin L, Yakunina MV, Borukhov S, Nilsson E, Holmfeldt K, Yutin N, Makarova KS, Koonin EV, Severinov KV, Leiman PG, Sokolova ML. Structure and function of virion RNA polymerase of a crAss-like phage. Nature 2021; 589:306-309. [PMID: 33208949 DOI: 10.1038/s41586-020-2921-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 09/08/2020] [Indexed: 01/29/2023]
Abstract
CrAss-like phages are a recently described expansive group of viruses that includes the most abundant virus in the human gut1-3. The genomes of all crAss-like phages encode a large virion-packaged protein2,4 that contains a DFDxD sequence motif, which forms the catalytic site in cellular multisubunit RNA polymerases (RNAPs)5. Here, using Cellulophaga baltica crAss-like phage phi14:2 as a model system, we show that this protein is a DNA-dependent RNAP that is translocated into the host cell along with the phage DNA and transcribes early phage genes. We determined the crystal structure of this 2,180-residue enzyme in a self-inhibited state, which probably occurs before virion packaging. This conformation is attained with the help of a cleft-blocking domain that interacts with the active site and occupies the cavity in which the RNA-DNA hybrid binds. Structurally, phi14:2 RNAP is most similar to eukaryotic RNAPs that are involved in RNA interference6,7, although most of the phi14:2 RNAP structure (nearly 1,600 residues) maps to a new region of the protein fold space. Considering this structural similarity, we propose that eukaryal RNA interference polymerases have their origins in phage, which parallels the emergence of the mitochondrial transcription apparatus8.
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Affiliation(s)
- Arina V Drobysheva
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Sofia A Panafidina
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Matvei V Kolesnik
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Evgeny I Klimuk
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia
| | - Leonid Minakhin
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Maria V Yakunina
- Peter the Great St Petersburg Polytechnic University, St Petersburg, Russia
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine at Stratford, Stratford, NJ, USA
| | - Emelie Nilsson
- Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University, Kalmar, Sweden
| | - Karin Holmfeldt
- Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University, Kalmar, Sweden
| | - Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USA
| | - Konstantin V Severinov
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, Russia.
- Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
| | - Petr G Leiman
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX, USA.
| | - Maria L Sokolova
- Center of Life Sciences, Skolkovo Institute of Science and Technology, Moscow, Russia.
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8
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Ovchinnikov SV, Bikmetov D, Livenskyi A, Serebryakova M, Wilcox B, Mangano K, Shiriaev DI, Osterman IA, Sergiev PV, Borukhov S, Vazquez-Laslop N, Mankin AS, Severinov K, Dubiley S. Mechanism of translation inhibition by type II GNAT toxin AtaT2. Nucleic Acids Res 2020; 48:8617-8625. [PMID: 32597957 PMCID: PMC7470980 DOI: 10.1093/nar/gkaa551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 06/05/2020] [Accepted: 06/17/2020] [Indexed: 12/25/2022] Open
Abstract
Type II toxin–antitoxins systems are widespread in prokaryotic genomes. Typically, they comprise two proteins, a toxin, and an antitoxin, encoded by adjacent genes and forming a complex in which the enzymatic activity of the toxin is inhibited. Under stress conditions, the antitoxin is degraded liberating the active toxin. Though thousands of various toxin–antitoxins pairs have been predicted bioinformatically, only a handful has been thoroughly characterized. Here, we describe the AtaT2 toxin from a toxin–antitoxin system from Escherichia coli O157:H7. We show that AtaT2 is the first GNAT (Gcn5-related N-acetyltransferase) toxin that specifically targets charged glycyl tRNA. In vivo, the AtaT2 activity induces ribosome stalling at all four glycyl codons but does not evoke a stringent response. In vitro, AtaT2 acetylates the aminoacyl moiety of isoaccepting glycyl tRNAs, thus precluding their participation in translation. Our study broadens the known target specificity of GNAT toxins beyond the earlier described isoleucine and formyl methionine tRNAs, and suggest that various GNAT toxins may have evolved to specificaly target other if not all individual aminoacyl tRNAs.
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Affiliation(s)
- Stepan V Ovchinnikov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia
| | - Dmitry Bikmetov
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia.,Institute of Gene Biology, Russian Academy of Science, 119334 Moscow, Russia
| | - Alexei Livenskyi
- Institute of Gene Biology, Russian Academy of Science, 119334 Moscow, Russia.,Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Marina Serebryakova
- Institute of Gene Biology, Russian Academy of Science, 119334 Moscow, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Brendan Wilcox
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia
| | - Kyle Mangano
- Center for Biomolecular Sciences, University of Illinois, Chicago, IL 60607, USA.,Department of Pharmaceutical Sciences, University of Illinois, Chicago, IL 60607, USA
| | - Dmitrii I Shiriaev
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Ilya A Osterman
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Department of Chemistry, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Petr V Sergiev
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Sergei Borukhov
- Department of Cell Biology and Neuroscience, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1489, USA
| | - Nora Vazquez-Laslop
- Center for Biomolecular Sciences, University of Illinois, Chicago, IL 60607, USA.,Department of Pharmaceutical Sciences, University of Illinois, Chicago, IL 60607, USA
| | - Alexander S Mankin
- Center for Biomolecular Sciences, University of Illinois, Chicago, IL 60607, USA.,Department of Pharmaceutical Sciences, University of Illinois, Chicago, IL 60607, USA
| | - Konstantin Severinov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia.,Waksman Institute for Microbiology, Piscataway, NJ 08854-8020, USA
| | - Svetlana Dubiley
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Institute of Gene Biology, Russian Academy of Science, 119334 Moscow, Russia
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9
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Wilcox B, Osterman I, Serebryakova M, Lukyanov D, Komarova E, Gollan B, Morozova N, Wolf YI, Makarova KS, Helaine S, Sergiev P, Dubiley S, Borukhov S, Severinov K. Escherichia coli ItaT is a type II toxin that inhibits translation by acetylating isoleucyl-tRNAIle. Nucleic Acids Res 2019; 46:7873-7885. [PMID: 29931259 PMCID: PMC6125619 DOI: 10.1093/nar/gky560] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 06/07/2018] [Indexed: 11/14/2022] Open
Abstract
Prokaryotic toxin-antitoxin (TA) modules are highly abundant and are involved in stress response and drug tolerance. The most common type II TA modules consist of two interacting proteins. The type II toxins are diverse enzymes targeting various essential intracellular targets. The antitoxin binds to cognate toxin and inhibits its function. Recently, TA modules whose toxins are GNAT-family acetyltransferases were described. For two such systems, the target of acetylation was shown to be aminoacyl-tRNA: the TacT toxin targets aminoacylated elongator tRNAs, while AtaT targets the amino acid moiety of initiating tRNAMet. We show that the itaRT gene pair from Escherichia coli encodes a TA module with acetyltransferase toxin ItaT that specifically and exclusively acetylates Ile-tRNAIle thereby blocking translation and inhibiting cell growth. ItaT forms a tight complex with the ItaR antitoxin, which represses the transcription of itaRT operon. A comprehensive bioinformatics survey of GNAT acetyltransferases reveals that enzymes encoded by validated or putative TA modules are common and form a distinct branch of the GNAT family tree. We speculate that further functional analysis of such TA modules will result in identification of enzymes capable of specifically targeting many, perhaps all, aminoacyl tRNAs.
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Affiliation(s)
- Brendan Wilcox
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia
| | - Ilya Osterman
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Lomonosov Moscow State University, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow 119992, Russia
| | - Marina Serebryakova
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Lomonosov Moscow State University, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow 119992, Russia
| | - Dmitry Lukyanov
- Lomonosov Moscow State University, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow 119992, Russia
| | - Ekaterina Komarova
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Lomonosov Moscow State University, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow 119992, Russia
| | - Bridget Gollan
- MRC Centre for Molecular Bacteriology and Infection, Flowers Building, Armstrong Road, Imperial College London, London SW7 2AZ, UK
| | - Natalia Morozova
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Peter the Great St. Petersburg State Polytechnic University, St. Petersburg, Russia
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Sophie Helaine
- MRC Centre for Molecular Bacteriology and Infection, Flowers Building, Armstrong Road, Imperial College London, London SW7 2AZ, UK
| | - Petr Sergiev
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Lomonosov Moscow State University, A.N. Belozersky Institute of Physico-Chemical Biology, Moscow 119992, Russia
| | - Svetlana Dubiley
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Institute of Gene Biology of the Russian Academy of Sciences, Moscow 119334, Russia
| | - Sergei Borukhov
- Department of Cell Biology, Rowan University School of Osteopathic Medicine at Stratford, Stratford, NJ 08084-1489, USA
| | - Konstantin Severinov
- Centre for Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Institute of Gene Biology of the Russian Academy of Sciences, Moscow 119334, Russia.,Waksman Institute for Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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10
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Sokolova M, Borukhov S, Lavysh D, Artamonova T, Khodorkovskii M, Severinov K. A non-canonical multisubunit RNA polymerase encoded by the AR9 phage recognizes the template strand of its uracil-containing promoters. Nucleic Acids Res 2017; 45:5958-5967. [PMID: 28402520 PMCID: PMC5449584 DOI: 10.1093/nar/gkx264] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 04/04/2017] [Indexed: 12/22/2022] Open
Abstract
AR9 is a giant Bacillus subtilis phage whose uracil-containing double-stranded DNA genome encodes distant homologs of β and β’ subunits of bacterial RNA polymerase (RNAP). The products of these genes are thought to assemble into two non-canonical multisubunit RNAPs - a virion RNAP (vRNAP) that is injected into the host along with phage DNA to transcribe early phage genes, and a non-virion RNAP (nvRNAP), which is synthesized during the infection and transcribes late phage genes. We purified the AR9 nvRNAP from infected B. subtilis cells and characterized its transcription activity in vitro. The AR9 nvRNAP requires uracils rather than thymines at specific conserved positions of late viral promoters. Uniquely, the nvRNAP recognizes the template strand of its promoters and is capable of specific initiation of transcription from both double- and single-stranded DNA. While the AR9 nvRNAP does not contain homologs of bacterial RNAP α subunits, it contains, in addition to the β and β’-like subunits, a phage protein gp226. The AR9 nvRNAP lacking gp226 is catalytically active but unable to bind to promoter DNA. Thus, gp226 is required for promoter recognition by the AR9 nvRNAP and may represent a new group of transcription initiation factors.
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Affiliation(s)
- Maria Sokolova
- Skolkovo Institute of Science and Technology, Skolkovo, 143025, Russia.,Peter the Great St.Petersburg Polytechnic University, Saint-Petersburg, 195251, Russia
| | - Sergei Borukhov
- Department of Cell Biology, Rowan University School of Osteopathic Medicine at Stratford, Stratford, NJ 08084-1489, USA
| | - Daria Lavysh
- Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia.,Institute of Antimicrobial Chemotherapy, Smolensk State Medical University, Smolensk, 214019, Russia
| | - Tatjana Artamonova
- Peter the Great St.Petersburg Polytechnic University, Saint-Petersburg, 195251, Russia
| | - Mikhail Khodorkovskii
- Peter the Great St.Petersburg Polytechnic University, Saint-Petersburg, 195251, Russia
| | - Konstantin Severinov
- Skolkovo Institute of Science and Technology, Skolkovo, 143025, Russia.,Peter the Great St.Petersburg Polytechnic University, Saint-Petersburg, 195251, Russia.,Institute of Molecular Genetics, Russian Academy of Sciences, Moscow, 123182, Russia.,Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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11
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Alhadid Y, Chung S, Lerner E, Taatjes DJ, Borukhov S, Weiss S. Studying transcription initiation by RNA polymerase with diffusion-based single-molecule fluorescence. Protein Sci 2017; 26:1278-1290. [PMID: 28370550 PMCID: PMC5477543 DOI: 10.1002/pro.3160] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/11/2017] [Accepted: 03/13/2017] [Indexed: 01/30/2023]
Abstract
Over the past decade, fluorescence-based single-molecule studies significantly contributed to characterizing the mechanism of RNA polymerase at different steps in transcription, especially in transcription initiation. Transcription by bacterial DNA-dependent RNA polymerase is a multistep process that uses genomic DNA to synthesize complementary RNA molecules. Transcription initiation is a highly regulated step in E. coli, but it has been challenging to study its mechanism because of its stochasticity and complexity. In this review, we describe how single-molecule approaches have contributed to our understanding of transcription and have uncovered mechanistic details that were not observed in conventional assays because of ensemble averaging.
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Affiliation(s)
- Yazan Alhadid
- Interdepartmental Program in Molecular, Cellular, and Integrative Physiology, University of California, Los Angeles, California, 90095
| | - SangYoon Chung
- Department of Chemistry & Biochemistry, University of California, Los Angeles, California, 90095
| | - Eitan Lerner
- Department of Chemistry & Biochemistry, University of California, Los Angeles, California, 90095
| | - Dylan J Taatjes
- Department of Chemistry & Biochemistry, University of Colorado, Boulder, Colorado, 80303
| | - Sergei Borukhov
- Rowan University School of Osteopathic Medicine, Stratford, New Jersey, 08084
| | - Shimon Weiss
- Interdepartmental Program in Molecular, Cellular, and Integrative Physiology, University of California, Los Angeles, California, 90095
- Department of Chemistry & Biochemistry, University of California, Los Angeles, California, 90095
- Molecular Biology Institute (MBI), University of California, Los Angeles, California, 90095
- California NanoSystems Institute, University of California, Los Angeles, California, 90095
- Department of Physiology, University of California, Los Angeles, California, 90095
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12
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Abstract
In many cases, initiation is rate limiting to transcription. This due in part to the multiple cycles of abortive transcription that delay promoter escape and the transition from initiation to elongation. Pausing of transcription in initiation can further delay promoter escape. The previously hypothesized pausing in initiation was confirmed by two recent studies from Duchi et al. 1 and from Lerner, Chung et al. 2 In both studies, pausing is attributed to a lack of forward translocation of the nascent transcript during initiation. However, the two works report on different pausing mechanisms. Duchi et al. report on pausing that occurs during initiation predominantly on-pathway of transcript synthesis. Lerner, Chung et al. report on pausing during initiation as a result of RNAP backtracking, which is off-pathway to transcript synthesis. Here, we discuss these studies, together with additional experimental results from single-molecule FRET focusing on a specific distance within the transcription bubble. We show that the results of these studies are complementary to each other and are consistent with a model involving two types of pauses in initiation: a short-lived pause that occurs in the translocation of a 6-mer nascent transcript and a long-lived pause that occurs as a result of 1-2 nucleotide backtracking of a 7-mer transcript.
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Affiliation(s)
- Eitan Lerner
- a Department of Chemistry & Biochemistry , University of California , Los Angeles , CA , USA
| | - Antonino Ingargiola
- a Department of Chemistry & Biochemistry , University of California , Los Angeles , CA , USA
| | - Jookyung J Lee
- b Rowan University School of Osteopathic Medicine , Stratford , NJ , USA
| | - Sergei Borukhov
- b Rowan University School of Osteopathic Medicine , Stratford , NJ , USA
| | - Xavier Michalet
- a Department of Chemistry & Biochemistry , University of California , Los Angeles , CA , USA
| | - Shimon Weiss
- a Department of Chemistry & Biochemistry , University of California , Los Angeles , CA , USA.,c Molecular Biology Institute , University of California , Los Angeles , CA , USA.,d Department of Physiology , University of California , Los Angeles , CA , USA
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13
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Lee J, Borukhov S. Bacterial RNA Polymerase-DNA Interaction-The Driving Force of Gene Expression and the Target for Drug Action. Front Mol Biosci 2016; 3:73. [PMID: 27882317 PMCID: PMC5101437 DOI: 10.3389/fmolb.2016.00073] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 10/24/2016] [Indexed: 11/17/2022] Open
Abstract
DNA-dependent multisubunit RNA polymerase (RNAP) is the key enzyme of gene expression and a target of regulation in all kingdoms of life. It is a complex multifunctional molecular machine which, unlike other DNA-binding proteins, engages in extensive and dynamic interactions (both specific and nonspecific) with DNA, and maintains them over a distance. These interactions are controlled by DNA sequences, DNA topology, and a host of regulatory factors. Here, we summarize key recent structural and biochemical studies that elucidate the fine details of RNAP-DNA interactions during initiation. The findings of these studies help unravel the molecular mechanisms of promoter recognition and open complex formation, initiation of transcript synthesis and promoter escape. We also discuss most current advances in the studies of drugs that specifically target RNAP-DNA interactions during transcription initiation and elongation.
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Affiliation(s)
- Jookyung Lee
- Department of Cell Biology, Rowan University School of Osteopathic Medicine Stratford, NJ, USA
| | - Sergei Borukhov
- Department of Cell Biology, Rowan University School of Osteopathic Medicine Stratford, NJ, USA
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14
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Lerner E, Chung S, Allen B, Shuang W, Jookyung LJ, Winson Shijia L, Wilson Logan G, Ingargiola A, Alhadid Y, Borukhov S, Strick T, Taatjes DJ, Weiss S. Pausing in Escherichia coli Transcription Initiation. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.1273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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15
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Yakunina M, Artamonova T, Borukhov S, Makarova KS, Severinov K, Minakhin L. A non-canonical multisubunit RNA polymerase encoded by a giant bacteriophage. Nucleic Acids Res 2015; 43:10411-20. [PMID: 26490960 PMCID: PMC4666361 DOI: 10.1093/nar/gkv1095] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/10/2015] [Indexed: 11/21/2022] Open
Abstract
The infection of Pseudomonas aeruginosa by the giant bacteriophage phiKZ is resistant to host RNA polymerase (RNAP) inhibitor rifampicin. phiKZ encodes two sets of polypeptides that are distantly related to fragments of the two largest subunits of cellular multisubunit RNAPs. Polypeptides of one set are encoded by middle phage genes and are found in the phiKZ virions. Polypeptides of the second set are encoded by early phage genes and are absent from virions. Here, we report isolation of a five-subunit RNAP from phiKZ-infected cells. Four subunits of this enzyme are cellular RNAP subunits homologs of the non-virion set; the fifth subunit is a protein of unknown function. In vitro, this complex initiates transcription from late phiKZ promoters in rifampicin-resistant manner. Thus, this enzyme is a non-virion phiKZ RNAP responsible for transcription of late phage genes. The phiKZ RNAP lacks identifiable assembly and promoter specificity subunits/factors characteristic for eukaryal, archaeal and bacterial RNAPs and thus provides a unique model for comparative analysis of the mechanism, regulation and evolution of this important class of enzymes.
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Affiliation(s)
- Maria Yakunina
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA
| | - Tatyana Artamonova
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia
| | - Sergei Borukhov
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Rowan University School of Osteopathic Medicine, Stratford, NJ 08084-1501, USA
| | - Kira S Makarova
- National Center for Biotechnology Information NLM, National Institutes of Health Bethesda, MD 20894, USA
| | - Konstantin Severinov
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA Skolkovo Institute of Science and Technology, Skolkovo, 143026, Russia
| | - Leonid Minakhin
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia Department of Molecular Biology and Biochemistry, Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8020, USA
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16
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Mekler V, Minakhin L, Borukhov S, Mustaev A, Severinov K. Coupling of downstream RNA polymerase-promoter interactions with formation of catalytically competent transcription initiation complex. J Mol Biol 2014; 426:3973-3984. [PMID: 25311862 DOI: 10.1016/j.jmb.2014.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/05/2014] [Accepted: 10/06/2014] [Indexed: 01/22/2023]
Abstract
Bacterial RNA polymerase (RNAP) makes extensive contacts with duplex DNA downstream of the transcription bubble in initiation and elongation complexes. We investigated the role of downstream interactions in formation of catalytically competent transcription initiation complex by measuring initiation activity of stable RNAP complexes with model promoter DNA fragments whose downstream ends extend from +3 to +21 relative to the transcription start site at +1. We found that DNA downstream of position +6 does not play a significant role in transcription initiation when RNAP-promoter interactions upstream of the transcription start site are strong and promoter melting region is AT rich. Further shortening of downstream DNA dramatically reduces efficiency of transcription initiation. The boundary of minimal downstream DNA duplex needed for efficient transcription initiation shifted further away from the catalytic center upon increasing the GC content of promoter melting region or in the presence of bacterial stringent response regulators DksA and ppGpp. These results indicate that the strength of RNAP-downstream DNA interactions has to reach a certain threshold to retain the catalytically competent conformation of the initiation complex and that establishment of contacts between RNAP and downstream DNA can be coupled with promoter melting. The data further suggest that RNAP interactions with DNA immediately downstream of the transcription bubble are particularly important for initiation of transcription. We hypothesize that these active center-proximal contacts stabilize the DNA template strand in the active center cleft and/or position the RNAP clamp domain to allow RNA synthesis.
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Affiliation(s)
- Vladimir Mekler
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, NJ 08854, USA.
| | - Leonid Minakhin
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, NJ 08854, USA
| | - Sergei Borukhov
- Rowan University School of Osteopathic Medicine, Stratford, NJ 08084, USA
| | - Arkady Mustaev
- Public Health Research Institute Center, New Jersey Medical School, Department of Microbiology and Molecular Genetics, University of Medicine and Dentistry of New Jersey, NJ 07103, USA
| | - Konstantin Severinov
- Waksman Institute of Microbiology, Rutgers, The State University of New Jersey, NJ 08854, USA; Department of Biochemistry and Molecular Biology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA; Institutes of Gene Biology and Molecular Genetics, Russian Academy of Sciences, Leninsky Avenue, 14, 119991 Moscow, Russia.
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17
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Kulikovsky A, Serebryakova M, Bantysh O, Metlitskaya A, Borukhov S, Severinov K, Dubiley S. The molecular mechanism of aminopropylation of peptide-nucleotide antibiotic microcin C. J Am Chem Soc 2014; 136:11168-75. [PMID: 25026542 DOI: 10.1021/ja505982c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Translation inhibitor microcin C (McC) is a heptapeptide with an aspartate α-carboxyl group linked to AMP via phosphoramidate bond. Modification of the McC phosphate by an aminopropyl moiety increases the biological activity by ~10-fold. Here, we determine the pathway of the aminopropylation reaction of McC. We show that the MccD enzyme uses S-adenosyl methionine to transfer 3-amino-3-carboxypropyl group onto a phosphate of an McC maturation intermediate consisting of adenylated heptapeptide. The carboxyl group is removed by the MccE enzyme, yielding mature McC. MccD is an inefficient enzyme that requires for its action the product of Escherichia coli mtn gene, a 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase, which hydrolyses 5'-methylthioadenosine, the product of MccD-catalyzed reaction, thus stimulating the amino-3-carboxypropylation reaction. Both MccD and MccE are capable of modifying McC-like compounds with divergent peptide moieties, opening way for preparation of more potent peptidyl-adenylates.
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Affiliation(s)
- Alexey Kulikovsky
- Institute of Gene Biology and ∥Institute of Molecular Genetics, Russian Academy of Sciences , Moscow 119991, Russia
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18
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Abstract
Bacterial transcription elongation factors GreA and GreB stimulate the intrinsic RNase activity of RNA polymerase (RNAP), thus helping the enzyme to read through pausing and arresting sites on DNA. Gre factors also accelerate RNAP transition from initiation to elongation. Here, we characterized the molecular mechanism by which Gre factors facilitate transcription at two Escherichia coli promoters, PrplN and PompX, that require GreA for optimal in vivo activity. Using in vitro transcription assays, KMnO(4) footprinting, and Fe(2+)-induced hydroxyl radical mapping, we show that during transcription initiation at PrplN and PompX in the absence of Gre factors, RNAP falls into a condition of promoter-proximal transcriptional arrest that prevents production of full-length transcripts both in vitro and in vivo. Arrest occurs when RNAP synthesizes 9-14-nucleotide-long transcripts and backtracks by 5-7 (PrplN) or 2-4 (PompX) nucleotides. Initiation factor sigma(70) contributes to the formation of arrested complexes at both promoters. The signal for promoter-proximal arrest at PrplN is bipartite and requires two elements: the extended -10 promoter element and the initial transcribed region from positions +2 to +6. GreA and GreB prevent arrest at PrplN and PompX by inducing cleavage of the 3'-proximal backtracked portion of RNA at the onset of arrested complex formation and stimulate productive transcription by allowing RNAP to elongate the 5'-proximal transcript cleavage products in the presence of substrates. We propose that promoter-proximal arrest is a common feature of many bacterial promoters and may represent an important physiological target of regulation by transcript cleavage factors.
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Affiliation(s)
- Ekaterina Stepanova
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, Stratford, New Jersey 08084, USA
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19
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Borukhov S, Nudler E. RNA polymerase: the vehicle of transcription. Trends Microbiol 2008; 16:126-34. [DOI: 10.1016/j.tim.2007.12.006] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 12/06/2007] [Accepted: 12/06/2007] [Indexed: 10/22/2022]
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20
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Epshtein V, Cardinale CJ, Ruckenstein AE, Borukhov S, Nudler E. An allosteric path to transcription termination. Mol Cell 2008; 28:991-1001. [PMID: 18158897 DOI: 10.1016/j.molcel.2007.10.011] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2007] [Revised: 07/18/2007] [Accepted: 10/10/2007] [Indexed: 01/22/2023]
Abstract
Transcription termination signals in bacteria occur in RNA as a strong hairpin followed by a stretch of U residues at the 3' terminus. To release the transcript, RNA polymerase (RNAP) is thought to translocate forward without RNA synthesis. Here we provide genetic and biochemical evidence supporting an alternative model in which extensive conformational changes across the enzyme lead to termination without forward translocation. In this model, flexible parts of the RNA exit channel (zipper, flap, and zinc finger) assist the initial step of hairpin folding (nucleation). The hairpin then invades the RNAP main channel, causing RNA:DNA hybrid melting, structural changes of the catalytic site, and DNA-clamp opening induced by interaction with the G(trigger)-loop. Our results envision the elongation complex as a flexible structure, not a rigid body, and establish basic principles of the termination pathway that are likely to be universal in prokaryotic and eukaryotic systems.
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Affiliation(s)
- Vitaly Epshtein
- Department of Biochemistry, New York University School of Medicine, New York, NY 10016, USA
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21
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Stepanova E, Lee J, Ozerova M, Semenova E, Datsenko K, Wanner BL, Severinov K, Borukhov S. Analysis of promoter targets for Escherichia coli transcription elongation factor GreA in vivo and in vitro. J Bacteriol 2007; 189:8772-85. [PMID: 17766423 PMCID: PMC2168603 DOI: 10.1128/jb.00911-07] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcription elongation factor GreA induces nucleolytic activity of bacterial RNA polymerase (RNAP). In vitro, transcript cleavage by GreA contributes to transcription efficiency by (i) suppressing pauses and arrests, (ii) stimulating RNAP promoter escape, and (iii) enhancing transcription fidelity. However, it is unclear which of these functions is (are) most relevant in vivo. By comparing global gene expression profiles of Escherichia coli strains lacking Gre factors and strains expressing either the wild type (wt) or a functionally inactive GreA mutant, we identified genes that are potential targets of GreA action. Data analysis revealed that in the presence of chromosomally expressed GreA, 19 genes are upregulated; an additional 105 genes are activated upon overexpression of the wt but not the mutant GreA. Primer extension reactions with selected transcription units confirmed the gene array data. The most prominent stimulatory effect (threefold to about sixfold) of GreA was observed for genes of ribosomal protein operons and the tna operon, suggesting that transcript cleavage by GreA contributes to optimal expression levels of these genes in vivo. In vitro transcription assays indicated that the stimulatory effect of GreA upon the transcription of these genes is mostly due to increased RNAP recycling due to facilitated promoter escape. We propose that transcript cleavage during early stages of initiation is thus the main in vivo function of GreA. Surprisingly, the presence of the wt GreA also led to the decreased transcription of many genes. The mechanism of this effect is unknown and may be indirect.
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Affiliation(s)
- Ekaterina Stepanova
- Department of Cell Biology, UMDNJ-SOM at Stratford, 2 Medical Center Drive, Stratford, NJ 08084-1489, USA
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22
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Cava F, Laptenko O, Borukhov S, Chahlafi Z, Blas-Galindo E, Gómez-Puertas P, Berenguer J. Control of the respiratory metabolism of Thermus thermophilus by the nitrate respiration conjugative element NCE. Mol Microbiol 2007; 64:630-46. [PMID: 17462013 DOI: 10.1111/j.1365-2958.2007.05687.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The strains of Thermus thermophilus that contain the nitrate respiration conjugative element (NCE) replace their aerobic respiratory chain by an anaerobic counterpart made of the Nrc-NADH dehydrogenase and the Nar-nitrate reductase in response to nitrate and oxygen depletion. This replacement depends on DnrS and DnrT, two homologues to sensory transcription factors encoded in a bicistronic operon by the NCE. DnrS is an oxygen-sensitive protein required in vivo to activate transcription on its own dnr promoter and on that of the nar operon, but not required for the expression of the nrc operon. In contrast, DnrT is required for the transcription of these three operons and also for the repression of nqo, the operon that encodes the major respiratory NADH dehydrogenase expressed during aerobic growth. Thermophilic in vitro assays revealed that low DnrT concentrations allows the recruitment of the T. thermophilus RNA polymerase sigma(A) holoenzyme to the nrc promoter and its transcription, whereas higher DnrT concentrations are required to repress transcription on the nqo promoter. In conclusion, our data show a complex autoinducible mechanism by which DnrT functions as the transcriptional switch that allows the NCE to take the control of the respiratory metabolism of its host during adaptation to anaerobic growth.
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Affiliation(s)
- Felipe Cava
- Centro de Biología Molecular Severo Ochoa, Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid 28049, Spain
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23
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Zlatanova J, McAllister WT, Borukhov S, Leuba SH. Single-molecule approaches reveal the idiosyncrasies of RNA polymerases. Structure 2006; 14:953-66. [PMID: 16765888 DOI: 10.1016/j.str.2006.03.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Revised: 02/05/2006] [Accepted: 03/23/2006] [Indexed: 11/16/2022]
Abstract
Recently developed single-molecule techniques have provided new insights into the function of one of the most complex and highly regulated processes in the cell--the transcription of the DNA template into RNA. This review discusses methods and results from this emerging field, and it puts them in perspective of existing biochemical and structural data.
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Affiliation(s)
- Jordanka Zlatanova
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071, USA.
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24
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Laptenko O, Kim SS, Lee J, Starodubtseva M, Cava F, Berenguer J, Kong XP, Borukhov S. pH-dependent conformational switch activates the inhibitor of transcription elongation. EMBO J 2006; 25:2131-41. [PMID: 16628221 PMCID: PMC1462974 DOI: 10.1038/sj.emboj.7601094] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Accepted: 03/22/2006] [Indexed: 11/08/2022] Open
Abstract
Gfh1, a transcription factor from Thermus thermophilus, inhibits all catalytic activities of RNA polymerase (RNAP). We characterized the Gfh1 structure, function and possible mechanism of action and regulation. Gfh1 inhibits RNAP by competing with NTPs for coordinating the active site Mg2+ ion. This coordination requires at least two aspartates at the tip of the Gfh1 N-terminal coiled-coil domain (NTD). The overall structure of Gfh1 is similar to that of the Escherichia coli transcript cleavage factor GreA, except for the flipped orientation of the C-terminal domain (CTD). We show that depending on pH, Gfh1-CTD exists in two alternative orientations. At pH above 7, it assumes an inactive 'flipped' orientation seen in the structure, which prevents Gfh1 from binding to RNAP. At lower pH, Gfh1-CTD switches to an active 'Gre-like' orientation, which enables Gfh1 to bind to and inhibit RNAP.
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Affiliation(s)
- Oleg Laptenko
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, Stratford, NJ, USA
| | - Seung-Sup Kim
- Department of Biochemistry, New York University School of Medicine, New York, NY, USA
| | - Jookyung Lee
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, Stratford, NJ, USA
| | - Marina Starodubtseva
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, Stratford, NJ, USA
| | - Fellipe Cava
- Centro de Biología Molecular ‘Severo Ochoa' CSIC-UAM, Campus de Cantoblanco, Madrid, Spain
| | - Jose Berenguer
- Centro de Biología Molecular ‘Severo Ochoa' CSIC-UAM, Campus de Cantoblanco, Madrid, Spain
| | - Xiang-Peng Kong
- Department of Biochemistry, New York University School of Medicine, New York, NY, USA
- Department of Biochemistry, New York University School of Medicine, New York, NY 10016, USA. Tel.: +1 212 263 7897; Fax: +1 212 263 8951; E-mail:
| | - Sergei Borukhov
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, Stratford, NJ, USA
- Department of Cell Biology, School of Osteopathic Medicine at Stratford, University of Medicine and Dentistry of New Jersey, 2-Medical Center drive, Rm B108, Stratford, NJ 08084, USA. Tel.:+1 856 566 6271; Fax: +1 856 566 6965; E-mail:
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25
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Tuske S, Sarafianos SG, Wang X, Hudson B, Sineva E, Mukhopadhyay J, Birktoft JJ, Leroy O, Ismail S, Clark AD, Dharia C, Napoli A, Laptenko O, Lee J, Borukhov S, Ebright RH, Arnold E. Inhibition of bacterial RNA polymerase by streptolydigin: stabilization of a straight-bridge-helix active-center conformation. Cell 2005; 122:541-52. [PMID: 16122422 PMCID: PMC2754413 DOI: 10.1016/j.cell.2005.07.017] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Revised: 06/03/2005] [Accepted: 07/13/2005] [Indexed: 11/17/2022]
Abstract
We define the target, mechanism, and structural basis of inhibition of bacterial RNA polymerase (RNAP) by the tetramic acid antibiotic streptolydigin (Stl). Stl binds to a site adjacent to but not overlapping the RNAP active center and stabilizes an RNAP-active-center conformational state with a straight-bridge helix. The results provide direct support for the proposals that alternative straight-bridge-helix and bent-bridge-helix RNAP-active-center conformations exist and that cycling between straight-bridge-helix and bent-bridge-helix RNAP-active-center conformations is required for RNAP function. The results set bounds on models for RNAP function and suggest strategies for design of novel antibacterial agents.
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Affiliation(s)
- Steven Tuske
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Stefan G. Sarafianos
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Xinyue Wang
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Brian Hudson
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Elena Sineva
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Jayanta Mukhopadhyay
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Jens J. Birktoft
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Olivier Leroy
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Sajida Ismail
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Arthur D. Clark
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Chhaya Dharia
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
| | - Andrew Napoli
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
| | - Oleg Laptenko
- Department of Cell Biology, UMDNJ, Stratford NJ 08084, USA
| | - Jookyung Lee
- Department of Cell Biology, UMDNJ, Stratford NJ 08084, USA
| | | | - Richard H. Ebright
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Waksman Institute, Rutgers University, Piscataway NJ 08854, USA
- Howard Hughes Medical Institute, Piscataway NJ 08854, USA
| | - Eddy Arnold
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway NJ 08854, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway NJ 08854, USA
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26
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Abstract
Transcription of E. coli lac operon by RNA polymerase (RNAP) is a classic example of how the basic functions of this enzyme, specifically the ability to recognize/bind promoters, melt the DNA and initiate RNA synthesis, is positively regulated by transcription activators, such as cyclic AMP-receptor protein, CRP, and negatively regulated by lac-repressor, LacI. In this review, we discuss the recent progress in structural and biochemical studies of RNAP and its binary and ternary complexes with CRP and lac promoter. With structural information now available for RNAP and models of binary and ternary elongation complexes, the interaction between these factors and RNAP can be modeled, and possible molecular mechanisms of their action can be inferred.
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Affiliation(s)
- Sergei Borukhov
- Department of Cell Biology, UMDNJ-SOM at Stratford, Stratford, NJ 08084, USA.
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27
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Abstract
Like transcription initiation, the elongation and termination stages of transcription cycle serve as important targets for regulatory factors in prokaryotic cells. In this review, we discuss the recent progress in structural and biochemical studies of three evolutionarily conserved elongation factors, GreA, NusA and Mfd. These factors affect RNA polymerase (RNAP) processivity by modulating transcription pausing, arrest, termination or anti-termination. With structural information now available for RNAP and models of ternary elongation complexes, the interaction between these factors and RNAP can be modelled, and possible molecular mechanisms of their action can be inferred. The models suggest that these factors interact with RNAP at or near its three major, nucleic acid-binding channels: Mfd near the upstream opening of the primary (DNA-binding) channel, NusA in the vicinity of both the primary channel and the RNA exit channel, and GreA within the secondary (backtracked RNA-binding) channel, and support the view that these channels are involved in the maintenance of RNAP processivity.
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Affiliation(s)
- Sergei Borukhov
- Department of Microbiology and Immunology, SUNY Health Sciences Center at Brooklyn, Brooklyn, NY 11203, USA.
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28
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Adelman K, Yuzenkova J, La Porta A, Zenkin N, Lee J, Lis JT, Borukhov S, Wang MD, Severinov K. Molecular Mechanism of Transcription Inhibition by Peptide Antibiotic Microcin J25. Mol Cell 2004; 14:753-62. [PMID: 15200953 DOI: 10.1016/j.molcel.2004.05.017] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Revised: 05/13/2004] [Accepted: 05/21/2004] [Indexed: 12/01/2022]
Abstract
21 amino acid peptide Microcin J25 (MccJ25) inhibits transcription by bacterial RNA polymerase (RNAP). MccJ25-resistance mutations cluster in the RNAP secondary channel through which incoming NTP substrates are thought to reach the catalytic center and the 3' end of the nascent RNA is likely to thread in backtracked transcription complexes. The secondary channel also accepts transcript cleavage factors GreA and GreB. Here, we demonstrate that MccJ25 inhibits GreA/GreB-dependent transcript cleavage, impedes formation of backtracked complexes, and can be crosslinked to the 3'-end of the nascent RNA in elongation complexes. These results place the MccJ25 binding site within the secondary channel. Moreover, single-molecule assays reveal that MccJ25 binding to a transcribing RNAP temporarily stops transcript elongation but has no effect on the elongation velocity between pauses. Kinetic analysis of single-molecule data allows us to put forward a model of transcription inhibition by MccJ25 that envisions the complete occlusion of the secondary channel by bound inhibitor.
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Affiliation(s)
- Karen Adelman
- Department of Molecular Biology and Biochemistry, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
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29
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Affiliation(s)
- Oleg Laptenko
- Morse Institute of Molecular Genetics, Department of Microbiology and Immunology, SUNY Health Science Center at Brooklyn, 450 Clarkson Avenue, Brooklyn, New York 11203-2098, USA
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30
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Laptenko O, Lee J, Lomakin I, Borukhov S. Transcript cleavage factors GreA and GreB act as transient catalytic components of RNA polymerase. EMBO J 2003; 22:6322-34. [PMID: 14633991 PMCID: PMC291851 DOI: 10.1093/emboj/cdg610] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2003] [Revised: 10/06/2003] [Accepted: 10/14/2003] [Indexed: 11/13/2022] Open
Abstract
Prokaryotic transcription elongation factors GreA and GreB stimulate intrinsic nucleolytic activity of RNA polymerase (RNAP). The proposed biological role of Gre-induced RNA hydrolysis includes transcription proofreading, suppression of transcriptional pausing and arrest, and facilitation of RNAP transition from transcription initiation to transcription elongation. Using an array of biochemical and molecular genetic methods, we mapped the interaction interface between Gre and RNAP and identified the key residues in Gre responsible for induction of nucleolytic activity in RNAP. We propose a structural model in which the C-terminal globular domain of Gre binds near the opening of the RNAP secondary channel, the N-terminal coiled-coil domain (NTD) protrudes inside the RNAP channel, and the tip of the NTD is brought to the immediate vicinity of RNAP catalytic center. Two conserved acidic residues D41 and E44 located at the tip of the NTD assist RNAP by coordinating the Mg2+ ion and water molecule required for catalysis of RNA hydrolysis. If so, Gre would be the first transcription factor known to directly participate in the catalytic act of RNAP.
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Affiliation(s)
- Oleg Laptenko
- Department of Microbiology and Immunology, SUNY Health Science Center at Brooklyn, 450 Clarkson Avenue, BSB 3-27, Brooklyn, NY 11203, USA
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31
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Epshtein V, Toulmé F, Rahmouni AR, Borukhov S, Nudler E. Transcription through the roadblocks: the role of RNA polymerase cooperation. EMBO J 2003; 22:4719-27. [PMID: 12970184 PMCID: PMC212720 DOI: 10.1093/emboj/cdg452] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2003] [Revised: 07/10/2003] [Accepted: 07/23/2003] [Indexed: 11/15/2022] Open
Abstract
During transcription, cellular RNA polymerases (RNAP) have to deal with numerous potential roadblocks imposed by various DNA binding proteins. Many such proteins partially or completely interrupt a single round of RNA chain elongation in vitro. Here we demonstrate that Escherichia coli RNAP can effectively read through the site-specific DNA-binding proteins in vitro and in vivo if more than one RNAP molecule is allowed to initiate from the same promoter. The anti-roadblock activity of the trailing RNAP does not require transcript cleavage activity but relies on forward translocation of roadblocked complexes. These results support a cooperation model of transcription whereby RNAP molecules behave as 'partners' helping one another to traverse intrinsic and extrinsic obstacles.
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Affiliation(s)
- Vitaly Epshtein
- Department of Biochemistry, New York University Medical Center, New York, NY 10016, USA
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32
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Abstract
The past three years have marked the breakthrough in our understanding of the structural and functional organization of RNA polymerase. The latest major advance was the high-resolution structures of bacterial RNA polymerase holoenzyme and the holoenzyme in complex with promoter DNA. Together with an array of genetic, biochemical and biophysical data accumulated to date, the structures provide a comprehensive view of dynamic interactions between the major components of transcription machinery during the early stages of the transcription cycle. They include the binding of sigma factor to the core enzyme, and the recognition of promoter sequences and DNA melting by holoenzyme, transcription initiation and promoter clearance.
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Affiliation(s)
- Sergei Borukhov
- Department of Microbiology and Immunology, SUNY Health Sciences Center, 450 Clarkson Avenue, Room BSB 3-27, Brooklyn, NY 11203, USA.
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33
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Abstract
In bacteria, sigma subunits direct the catalytically competent RNA polymerase core enzyme to promoters. Recent advances in our understanding of bacterial RNA polymerase reveal that sigma subunits are intimately involved in all aspects of transcription initiation including promoter location, promoter melting, initiation of RNA synthesis, abortive initiation and promoter escape.
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Affiliation(s)
- Sergei Borukhov
- SUNY Health Sciences Center at Brooklyn, Brooklyn, NY 11203, USA
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34
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Vassylyeva MN, Lee J, Sekine SI, Laptenko O, Kuramitsu S, Shibata T, Inoue Y, Borukhov S, Vassylyev DG, Yokoyama S. Purification, crystallization and initial crystallographic analysis of RNA polymerase holoenzyme from Thermus thermophilus. Acta Crystallogr D Biol Crystallogr 2002; 58:1497-500. [PMID: 12198314 DOI: 10.1107/s0907444902011770] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2002] [Accepted: 07/03/2002] [Indexed: 11/10/2022]
Abstract
RNA polymerase holoenzyme from Thermus thermophilus, consisting of six protein subunits (alpha(2), beta, beta', omega and sigma(70)) and having a total molecular mass of about 450 kDa, was purified and crystallized by the hanging-drop vapour-diffusion technique under mild near-physiological conditions. The crystals diffract beyond 3 A resolution. Careful analysis of diffraction data revealed that the crystals belong to space group P3(2), with unit-cell parameters a = b = 236.35, c = 249.04 A, and have perfect twinning along the threefold axis. A complete data set at 3 A resolution was collected and an unambiguous molecular-replacement solution was found using the structure of T. aquaticus RNA polymerase core enzyme as a search model. The refinement of structure and model building of the sigma(70) subunit is now in progress.
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Affiliation(s)
- Marina N Vassylyeva
- Genomic Sciences Center (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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35
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Vassylyev DG, Sekine S, Laptenko O, Lee J, Vassylyeva MN, Borukhov S, Yokoyama S. Crystal structure of a bacterial RNA polymerase holoenzyme at 2.6 Å resolution. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302085318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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36
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Vassylyev DG, Sekine S, Laptenko O, Lee J, Vassylyeva MN, Borukhov S, Yokoyama S. Structural studies of bacterial transcription initiation. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302097271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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37
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Vassylyev DG, Sekine SI, Laptenko O, Lee J, Vassylyeva MN, Borukhov S, Yokoyama S. Crystal structure of a bacterial RNA polymerase holoenzyme at 2.6 A resolution. Nature 2002; 417:712-9. [PMID: 12000971 DOI: 10.1038/nature752] [Citation(s) in RCA: 623] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In bacteria, the binding of a single protein, the initiation factor sigma, to a multi-subunit RNA polymerase core enzyme results in the formation of a holoenzyme, the active form of RNA polymerase essential for transcription initiation. Here we report the crystal structure of a bacterial RNA polymerase holoenzyme from Thermus thermophilus at 2.6 A resolution. In the structure, two amino-terminal domains of the sigma subunit form a V-shaped structure near the opening of the upstream DNA-binding channel of the active site cleft. The carboxy-terminal domain of sigma is near the outlet of the RNA-exit channel, about 57 A from the N-terminal domains. The extended linker domain forms a hairpin protruding into the active site cleft, then stretching through the RNA-exit channel to connect the N- and C-terminal domains. The holoenzyme structure provides insight into the structural organization of transcription intermediate complexes and into the mechanism of transcription initiation.
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Affiliation(s)
- Dmitry G Vassylyev
- Cellular Signaling Laboratory, RIKEN Harima Institute at Spring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo, Hyogo 679-5148, Japan.
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38
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Affiliation(s)
- S Borukhov
- Department of Microbiology and Immunology, State University of New York Health Science Center, Brooklyn, New York 11203, USA
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39
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Temiakov D, Mentesana PE, Ma K, Mustaev A, Borukhov S, McAllister WT. The specificity loop of T7 RNA polymerase interacts first with the promoter and then with the elongating transcript, suggesting a mechanism for promoter clearance. Proc Natl Acad Sci U S A 2000; 97:14109-14. [PMID: 11095736 PMCID: PMC18879 DOI: 10.1073/pnas.250473197] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During the early stages of transcription, T7 RNA polymerase forms an unstable initiation complex that synthesizes and releases transcripts 2-8 nt in length before disengaging from the promoter and isomerizing to a stable elongation complex. In this study, we used RNA small middle dotprotein and RNA small middle dotDNA crosslinking methods to probe the location of newly synthesized RNA in halted elongation complexes. The results indicate that the RNA in an elongation complex remains in an RNA small middle dotDNA hybrid for about 8 nt from the site of nucleotide addition and emerges to the surface of the enzyme about 12 nt from the addition site. Strikingly, as the transcript leaves its hybrid with the template, the crosslinks it forms with the RNA polymerase involve a portion of a hairpin loop (the specificity loop) that makes specific contacts with the binding region of the promoter during initiation. This observation suggests that the specificity loop may have a dual role in transcription, binding first to the promoter and subsequently interacting with the RNA product. It seems likely that association of the nascent RNA with the specificity loop facilitates disengagement from the promoter and is an important part of the process that leads to a stable elongation complex.
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Affiliation(s)
- D Temiakov
- Morse Institute of Molecular Genetics, Department of Microbiology, State University of New York Health Science Center at Brooklyn, 450 Clarkson Avenue, Box 44, Brooklyn, NY 11203-2098, USA
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40
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Kulish D, Lee J, Lomakin I, Nowicka B, Das A, Darst S, Normet K, Borukhov S. The functional role of basic patch, a structural element of Escherichia coli transcript cleavage factors GreA and GreB. J Biol Chem 2000; 275:12789-98. [PMID: 10777576 DOI: 10.1074/jbc.275.17.12789] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The transcript cleavage factors GreA and GreB of Escherichia coli are involved in the regulation of transcription elongation. The surface charge distribution analysis of their three-dimensional structures revealed that the N-terminal domains of GreA and GreB contain a small and large basic "patch," respectively. To elucidate the functional role of basic patch, mutant Gre proteins were engineered in which the size and charge distribution of basic patch were modified and characterized biochemically. We found that Gre mutants lacking basic patch or carrying basic patch of decreased size bind to RNA polymerase and induce transcript cleavage reaction in minimally backtracked ternary elongation complex (TEC) with the same efficiency as the wild type factors. However, they exhibit substantially lower readthrough and cleavage activities toward extensively backtracked and arrested TECs and display decreased efficiency of photocross-linking to the RNA 3'-terminus. Unlike wild type factors, basic patch-less Gre mutants are unable to complement the thermosensitive phenotype of GreA(-):GreB(-) E. coli strain. The large basic patch is required but not sufficient for the induction of GreB-type cleavage reaction and for the cleavage of arrested TECs. Our results demonstrate that the basic patch residues are not directly involved in the induction of transcript cleavage reaction and suggest that the primary role of basic patch is to anchor the nascent RNA in TEC. These interactions are essential for the readthrough and antiarrest activities of Gre factors and, apparently, for their in vivo functions.
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Affiliation(s)
- D Kulish
- Department of Microbiology and Immunology, State University of New York, Health Science Center at Brooklyn, New York 11203, USA
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41
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Polyakov A, Richter C, Malhotra A, Koulich D, Borukhov S, Darst SA. Visualization of the binding site for the transcript cleavage factor GreB on Escherichia coli RNA polymerase. J Mol Biol 1998; 281:465-73. [PMID: 9698562 DOI: 10.1006/jmbi.1998.1958] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The structure of Escherichia coli core RNA polymerase (RNAP) complexed with the transcript cleavage factor GreB was determined from electron micrographs of negatively stained, flattened helical crystals. A binding assay was developed to establish that GreB was incorporated into the RNA polymerase crystals with high occupancy through interactions between the globular C-terminal domain and the RNA polymerase. Comparison of the core RNAP:GreB structure with the previously determined structure of core RNAP located the GreB binding site on one face of the RNA polymerase, next to but not in the 25 A-diameter channel of RNA polymerase.
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Affiliation(s)
- A Polyakov
- Laboratory of Molecular Biophysics, The Rockefeller University, 1230 York Avenue, New York, NY, 10021, USA
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42
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Abstract
The prokaryotic transcription factors GreA and GreB are involved in the regulation of transcript elongation by RNA polymerase (RNAP). Their known activities include suppression of transcription arrest, enhancement of transcription fidelity, and facilitation of the transition from abortive initiation to productive elongation. Presumably, Gre proteins exert their functions by altering the conformation of the enzyme in ternary elongation complexes (TEC) and inducing the cleavage of nascent RNA. GreA and GreB have a similar structural organization and consist of two domains: a C-terminal globular and an extended N-terminal coiled-coil domain. To investigate the functional roles of Gre domains, we expressed separately the N and C-terminal domains of GreA (NTD and CTD, respectively) and characterized their activities with in vitro assays. We demonstrate that the NTD possesses the residual transcript cleavage activity of the wild-type GreA. The CTD does not display any nucleolytic activity; however, it substantially increases the cleavage activity of the NTD. In contrast to NTD, the CTD competes with GreA and GreB for binding to RNAP and inhibits their transcript cleavage and antiarrest activities. Both domains individually and together inhibit transcription elongation. From these results we conclude that the NTD is responsible for the GreA induction of nucleolytic activity while the CTD determines the binding of GreA to RNAP. Both domains are required for full functional activity of GreA.
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Affiliation(s)
- D Koulich
- Department of Microbiology and Immunology, State University of New York Health Science Center at Brooklyn 11203, USA
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43
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Koulich D, Orlova M, Malhotra A, Sali A, Darst SA, Borukhov S. Domain organization of Escherichia coli transcript cleavage factors GreA and GreB. J Biol Chem 1997; 272:7201-10. [PMID: 9054416 DOI: 10.1074/jbc.272.11.7201] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The GreA and GreB proteins of Escherichia coli induce cleavage of the nascent transcript in ternary elongation complexes of RNA polymerase. Gre factors are presumed to have two biologically important and evolutionarily conserved functions: the suppression of elongation arrest and the enhancement of transcription fidelity. A three-dimensional structure of GreB was generated by homology modeling on the basis of the known crystal structure of GreA. Both factors display similar overall architecture and surface charge distribution, with characteristic C-terminal globular and N-terminal coiled-coil domains. One major difference between the two factors is the "basic patch" on the surface of the coiled-coil domain, which is much larger in GreB than in GreA. In both proteins, a site near the basic patch cross-links to the 3' terminus of RNA in the ternary transcription complex. GreA/GreB hybrid molecules were constructed by genetic engineering in which the N-terminal domain of one protein was fused to the C-terminal domain of the other. In the hybrid molecules, both the coiled-coil and the globular domains contribute to specific binding of Gre factors to RNA polymerase, whereas the antiarrest activity and the GreA or GreB specificity of transcript cleavage is determined by the N-terminal domain. These results implicate the basic patch of the N-terminal coiled-coil domain as an important functional element responsible for the interactions with nascent transcript and determining the size of the RNA fragment to be excised during the course of the cleavage reaction.
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Affiliation(s)
- D Koulich
- Department of Microbiology and Immunology, State University of New York, Health Science Center at Brooklyn, Brooklyn, New York 11203, USA
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Kashlev M, Nudler E, Severinov K, Borukhov S, Komissarova N, Goldfarb A. Histidine-tagged RNA polymerase of Escherichia coli and transcription in solid phase. Methods Enzymol 1996; 274:326-34. [PMID: 8902816 DOI: 10.1016/s0076-6879(96)74028-4] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- M Kashlev
- Public Health Research Institute, New York, New York 10016, USA
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Affiliation(s)
- S Borukhov
- Department of Microbiology and Immunology, State University of New York, Health Science Center at Brooklyn 11203, USA
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Abstract
The GreA and GreB transcript cleavage factors of Escherichia coli suppress elongation arrest and may have a proofreading role in transcription. With the use of E. coli greA-greB- mutant, RNA polymerase is demonstrated to possess substantial intrinsic transcript cleavage activity. Mildly alkaline pH mimics the effect of the Gre proteins by inducing transcript cleavage in ternary complexes and antagonizing elongation arrest through a cleavage-and-restart reaction. Thus, transcript cleavage constitutes the second enzymological activity of RNA polymerase along with polymerization/pyrophosphorolysis of RNA, whereas the Gre proteins merely enhance this intrinsic property.
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Affiliation(s)
- M Orlova
- Public Health Research Institute, New York, NY 10016, USA
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Stebbins CE, Borukhov S, Orlova M, Polyakov A, Goldfarb A, Darst SA. Crystal structure of the GreA transcript cleavage factor from Escherichia coli. Nature 1995; 373:636-40. [PMID: 7854424 DOI: 10.1038/373636a0] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Transcription elongation factors stimulate the activity of DNA-dependent RNA polymerases by increasing the overall elongation rate and the completion of RNA chains. One group of such factors, which includes Escherichia coli GreA, GreB and eukaryotic SII (TFIIS), acts by inducing hydrolytic cleavage of the transcript within the RNA polymerase, followed by release of the 3'-terminal fragment. Here we report the crystal structure of GreA at 2.2 A resolution. The structure contains an amino-terminal domain consisting of an antiparallel alpha-helical coiled-coil dimer which extends into solution, reminiscent of the coiled coil in seryl-tRNA synthetases. A site near the tip of the coiled-coil 'finger' plays a direct role in the transcript cleavage reaction by contacting the 3'-end of the transcript. The structure exhibits an unusual asymmetric charge distribution which indicates the manner in which GreA interacts with the RNA polymerase elongation complex.
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Affiliation(s)
- C E Stebbins
- Rockefeller University, New York, New York 10021
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Darst SA, Stebbins CE, Borukhov S, Orlova M, Feng G, Landick R, Goldfarb A. Crystallization of GreA, a transcript cleavage factor from Escherichia coli. J Mol Biol 1994; 242:582-5. [PMID: 7932713 DOI: 10.1006/jmbi.1994.1603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
GreA is a 17.6 kDa protein from Escherichia coli that induces cleavage of the nascent transcript in the elongating complex of RNA polymerase, followed by release of the 3'-terminal fragment. Crystals of GreA have been obtained from polyethylene glycol 4000, 2-propanol and sodium citrate, pH 5.6 and have been propagated by a novel seeding procedure. The crystals diffract beyond 2 A resolution and belong to the orthorhombic space group P2(1)2(1)2(1), with cell dimensions a = 101.7 A, b = 42.22 A, c = 40.05 A and with one molecule in the asymmetric unit.
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Affiliation(s)
- S A Darst
- Rockefeller University, New York, NY 10021
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Borukhov S, Goldfarb A. Recombinant Escherichia coli RNA polymerase: purification of individually overexpressed subunits and in vitro assembly. Protein Expr Purif 1993; 4:503-11. [PMID: 8286946 DOI: 10.1006/prep.1993.1066] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
New improved methods were developed for the purification to apparent homogeneity of alpha, beta, beta', and sigma subunits of Escherichia coli RNA polymerase (RNAP) from corresponding overproducing strains. The purified subunits were assembled into enzymatically active RNAP holoenzyme (alpha 2 beta beta' sigma) using the optimal subunit molar ratio (alpha:beta:beta':sigma = 2:8:4:1) at a total protein concentration of 0.5 mg/ml. The presence of sigma subunit and 10 microM ZnCl2 in the reconstitution mixture increased the yield of RNAP approximately 4 times. The assembled RNA polymerase was purified by two successive chromatographic steps using size-exclusion Superose 6 and anion exchange Mono Q FPLC columns, which resulted in the electrophoretically homogeneous holoenzyme with overall yield of 56%. The specific activity of the recombinant RNAP estimated by the standard T4 transcription assay was 6.5 nmol of [3H]UTP incorporated into acid-insoluble RNA product per microgram of RNAP per 1 h.
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Affiliation(s)
- S Borukhov
- Public Health Research Institute, New York, New York 10016
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Borukhov S, Sagitov V, Josaitis CA, Gourse RL, Goldfarb A. Two modes of transcription initiation in vitro at the rrnB P1 promoter of Escherichia coli. J Biol Chem 1993; 268:23477-82. [PMID: 8226874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The rrnB P1 promoter of Escherichia coli (starting sequence C-4-A-3-C-2-C-1-A+1-C+2-U+3-G+4) forms a binary complex with RNA polymerase that is highly unstable and requires the presence of transcription substrates ATP and CTP for stabilizing the enzyme-DNA association (Gourse, R. L. (1988) Nucleic Acids Res. 16, 9789-9809). We show that in the absence of UTP and GTP the stabilization is accomplished by short RNA oligomers synthesized in an unusual "-3-->" mode whereby the primer initiated at the +1 site presumably slips back by three nucleotides into the -3 site and is then extended yielding stable ternary complexes. By contrast, short oligomers initiated in the conventional "+1-->" mode without slippage do not exert the stabilization effect and are readily aborted from the promoter complex. The stable -3-->ternary complexes carry sigma factor but otherwise resemble elongation complexes in their high salt stability and in the fact that they are formed with a mutant RNA polymerase deficient in promoter binding. A model is proposed explaining the stability of the -3-->ternary complexes by RNA slipping into a putative "tight RNA binding site" in RNA polymerase which is normally occupied by RNA during elongation.
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Affiliation(s)
- S Borukhov
- Public Health Research Institute, New York, New York 10016
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