1
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Ye J, Kan CH, Yang X, Ma C. Inhibition of bacterial RNA polymerase function and protein-protein interactions: a promising approach for next-generation antibacterial therapeutics. RSC Med Chem 2024; 15:1471-1487. [PMID: 38784472 PMCID: PMC11110800 DOI: 10.1039/d3md00690e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 03/25/2024] [Indexed: 05/25/2024] Open
Abstract
The increasing prevalence of multidrug-resistant pathogens necessitates the urgent development of new antimicrobial agents with innovative modes of action for the next generation of antimicrobial therapy. Bacterial transcription has been identified and widely studied as a viable target for antimicrobial development. The main focus of these studies has been the discovery of inhibitors that bind directly to the core enzyme of RNA polymerase (RNAP). Over the past two decades, substantial advancements have been made in understanding the properties of protein-protein interactions (PPIs) and gaining structural insights into bacterial RNAP and its associated factors. This has led to the crucial role of computational methods in aiding the identification of new PPI inhibitors to affect the RNAP function. In this context, bacterial transcriptional PPIs present promising, albeit challenging, targets for the creation of new antimicrobials. This review will succinctly outline the structural foundation of bacterial transcription networks and provide a summary of the known small molecules that target transcription PPIs.
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Affiliation(s)
- Jiqing Ye
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University Kowloon Hong Kong SAR China
- School of Pharmacy, Inflammation and Immune Mediated Diseases Laboratory of Anhui Province, Anhui Medical University Hefei 230032 China
| | - Cheuk Hei Kan
- Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital Shatin Hong Kong SAR China
| | - Xiao Yang
- Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital Shatin Hong Kong SAR China
| | - Cong Ma
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University Kowloon Hong Kong SAR China
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2
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Carvajal-Garcia J, Bracey H, Johnson AE, Hernandez Viera AJ, Egli M, Simsek EN, Jaremba EA, Kim K, Merrikh H. A small molecule that inhibits the evolution of antibiotic resistance. NAR MOLECULAR MEDICINE 2024; 1:ugae001. [PMID: 38911259 PMCID: PMC11188740 DOI: 10.1093/narmme/ugae001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/11/2023] [Accepted: 01/04/2024] [Indexed: 06/25/2024]
Abstract
Antibiotic resistance rapidly develops against almost all available therapeutics. Therefore, searching for new antibiotics to overcome the problem of antibiotic resistance alone is insufficient. Given that antibiotic resistance can be driven by mutagenesis, an avenue for preventing it is the inhibition of mutagenic processes. We previously showed that the DNA translocase Mfd is mutagenic and accelerates antibiotic resistance development. Here, we present our discovery of a small molecule that inhibits Mfd-dependent mutagenesis, ARM-1 (anti-resistance molecule 1). We found ARM-1 using a high-throughput, small molecule, in vivo screen. Using biochemical assays, we characterized the mechanism by which ARM-1 inhibits Mfd. Critically, we found that ARM-1 reduces mutagenesis and significantly delays antibiotic resistance development across highly divergent bacterial pathogens. These results demonstrate that the mutagenic proteins accelerating evolution can be directly inhibited. Furthermore, our findings suggest that Mfd inhibition, alongside antibiotics, is a potentially effective approach for prevention of antibiotic resistance development during treatment of infections.
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Affiliation(s)
| | - Harrison Bracey
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Anna E Johnson
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | | | - Martin Egli
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Esra N Simsek
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Emily A Jaremba
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Kwangho Kim
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Houra Merrikh
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
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3
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Paudel BP, Xu ZQ, Jergic S, Oakley AJ, Sharma N, Brown SHJ, Bouwer JC, Lewis PJ, Dixon NE, van Oijen AM, Ghodke H. Mechanism of transcription modulation by the transcription-repair coupling factor. Nucleic Acids Res 2022; 50:5688-5712. [PMID: 35641110 PMCID: PMC9177983 DOI: 10.1093/nar/gkac449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 05/06/2022] [Accepted: 05/13/2022] [Indexed: 11/27/2022] Open
Abstract
Elongation by RNA polymerase is dynamically modulated by accessory factors. The transcription-repair coupling factor (TRCF) recognizes paused/stalled RNAPs and either rescues transcription or initiates transcription termination. Precisely how TRCFs choose to execute either outcome remains unclear. With Escherichia coli as a model, we used single-molecule assays to study dynamic modulation of elongation by Mfd, the bacterial TRCF. We found that nucleotide-bound Mfd converts the elongation complex (EC) into a catalytically poised state, presenting the EC with an opportunity to restart transcription. After long-lived residence in this catalytically poised state, ATP hydrolysis by Mfd remodels the EC through an irreversible process leading to loss of the RNA transcript. Further, biophysical studies revealed that the motor domain of Mfd binds and partially melts DNA containing a template strand overhang. The results explain pathway choice determining the fate of the EC and provide a molecular mechanism for transcription modulation by TRCF.
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Affiliation(s)
- Bishnu P Paudel
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Zhi-Qiang Xu
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Slobodan Jergic
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Aaron J Oakley
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Nischal Sharma
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
| | - Simon H J Brown
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - James C Bouwer
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Peter J Lewis
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Nicholas E Dixon
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia.,ARC Industrial Transformation Training Centre for Cryo-electron Microscopy of Membrane Proteins, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Harshad Ghodke
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW 2522, Australia.,Illawarra Health and Medical Research Institute, Wollongong, NSW 2522, Australia
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4
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Single-molecule studies of helicases and translocases in prokaryotic genome-maintenance pathways. DNA Repair (Amst) 2021; 108:103229. [PMID: 34601381 DOI: 10.1016/j.dnarep.2021.103229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 11/22/2022]
Abstract
Helicases involved in genomic maintenance are a class of nucleic-acid dependent ATPases that convert the energy of ATP hydrolysis into physical work to execute irreversible steps in DNA replication, repair, and recombination. Prokaryotic helicases provide simple models to understand broadly conserved molecular mechanisms involved in manipulating nucleic acids during genome maintenance. Our understanding of the catalytic properties, mechanisms of regulation, and roles of prokaryotic helicases in DNA metabolism has been assembled through a combination of genetic, biochemical, and structural methods, further refined by single-molecule approaches. Together, these investigations have constructed a framework for understanding the mechanisms that maintain genomic integrity in cells. This review discusses recent single-molecule insights into molecular mechanisms of prokaryotic helicases and translocases.
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5
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Deaconescu AM. Mfd - at the crossroads of bacterial DNA repair, transcriptional regulation and molecular evolvability. Transcription 2021; 12:156-170. [PMID: 34674614 PMCID: PMC8632110 DOI: 10.1080/21541264.2021.1982628] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/06/2021] [Accepted: 09/14/2021] [Indexed: 12/21/2022] Open
Abstract
For survival, bacteria need to continuously evolve and adapt to complex environments, including those that may impact the integrity of the DNA, the repository of genetic information to be passed on to future generations. The multiple factors of DNA repair share the substrate on which they operate with other key cellular machineries, principally those of replication and transcription, implying a high degree of coordination of DNA-based activities. In this review, I focus on progress made in the understanding of the protein factors operating at the crossroads of these three fundamental processes, with emphasis on the mutation frequency decline protein (Mfd, aka TRCF). Although Mfd research has a rich history that goes back in time for more than half a century, recent reports hint that much remains to be uncovered. I argue that besides being a transcription-repair coupling factor (TRCF), Mfd is also a global regulator of transcription and a pro-mutagenic factor, and that the way it interfaces with transcription, replication and nucleotide excision repair makes it an attractive candidate for the development of strategies to curb molecular evolution, hence, antibiotic resistance.
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Affiliation(s)
- Alexandra M. Deaconescu
- CONTACT Alexandra M. Deaconescu Molecular Biology, Cell Biology and Biochemistry, Laboratories of Molecular Medicine, Brown University, 70 Ship St. G-E4, Providence, RI02903, USA
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6
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Shi J, Wen A, Zhao M, Jin S, You L, Shi Y, Dong S, Hua X, Zhang Y, Feng Y. Structural basis of Mfd-dependent transcription termination. Nucleic Acids Res 2021; 48:11762-11772. [PMID: 33068413 PMCID: PMC7672476 DOI: 10.1093/nar/gkaa904] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/26/2020] [Accepted: 10/01/2020] [Indexed: 11/16/2022] Open
Abstract
Mfd-dependent transcription termination plays an important role in transcription-coupled DNA repair, transcription-replication conflict resolution, and antimicrobial resistance development. Despite extensive studies, the molecular mechanism of Mfd-dependent transcription termination in bacteria remains unclear, with several long-standing puzzles. How Mfd is activated by stalled RNA polymerase (RNAP) and how activated Mfd translocates along the DNA are unknown. Here, we report the single-particle cryo-electron microscopy structures of T. thermophilus Mfd-RNAP complex with and without ATPγS. The structures reveal that Mfd undergoes profound conformational changes upon activation, contacts the RNAP β1 domain and its clamp, and pries open the RNAP clamp. These structures provide a foundation for future studies aimed at dissecting the precise mechanism of Mfd-dependent transcription termination and pave the way for rational drug design targeting Mfd for the purpose of tackling the antimicrobial resistance crisis.
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Affiliation(s)
- Jing Shi
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China.,Department of Pathology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.,Zhejiang Provincial Key Laboratory of Immunity and Inflammatory diseases, Hangzhou 310058, China
| | - Aijia Wen
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Minxing Zhao
- Department of Emergency Medicine of the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Sha Jin
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Linlin You
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yue Shi
- Department of Pathology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Shuling Dong
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Xiaoting Hua
- Department of Infectious Disease, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.,Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou 310058, China
| | - Yu Zhang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai 200032, China
| | - Yu Feng
- Department of Biophysics, Zhejiang University School of Medicine, Hangzhou 310058, China.,Department of Pathology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.,Zhejiang Provincial Key Laboratory of Immunity and Inflammatory diseases, Hangzhou 310058, China
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7
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Han S, Gong Z, Liang T, Chen Y, Xie J. The role of Mfd in Mycobacterium tuberculosis physiology and underlying regulatory network. Microbiol Res 2021; 246:126718. [PMID: 33588338 DOI: 10.1016/j.micres.2021.126718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 12/23/2022]
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis with millions of deaths annually, remains one of the most formidable pathogen to global public health. As the most successful intracellular pathogens, Mtb can spatiotemporally coordinate the transcription and translation timely to reconcile the inevitable transcription-replication conflicts. Mutation frequency decline (Mfd) is a bacterial ATP-dependent DNA translocase that couples DNA repair to transcription via hydrolyzing ATP as energy, which preferentially acts on the damaged DNA transcribed strand to rescue stalled RNAP or dissociate RNAP to terminate the transcription depending on impediment severity, mitigating the damage to bacteria. In addition to the traditional damage repair effect, Mfd may also promote bacteria mutagenesis under stresses and boost the drug resistance. Mfd is widespread among bacteria and intensively studied, but there are very few studies in Mycobacteria, especially Mtb. In this review, the structure, function and mechanism characteristics of Mfd in Mtb (MtbMfd, Rv1020) are explored, with emphasis on the regulatory network of MtbMfd and its potential as a prime target for antibiotic drugs against tuberculosis.
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Affiliation(s)
- Shuang Han
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, Ministry of Education, Chongqing Municipal Key Laboratory of Karst Environment, School of Life Sciences, Southwest University, Beibei, Chongqing, 400715, China
| | - Zhen Gong
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, Ministry of Education, Chongqing Municipal Key Laboratory of Karst Environment, School of Life Sciences, Southwest University, Beibei, Chongqing, 400715, China
| | - Tian Liang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, Ministry of Education, Chongqing Municipal Key Laboratory of Karst Environment, School of Life Sciences, Southwest University, Beibei, Chongqing, 400715, China
| | - Yu Chen
- Department of Tuberculosis, Shenyang Tenth People's Hospital and Shenyang Chest Hospital, Shenyang, Liaoning Province, 110044, China.
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, Ministry of Education, Chongqing Municipal Key Laboratory of Karst Environment, School of Life Sciences, Southwest University, Beibei, Chongqing, 400715, China.
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8
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Kang JY, Llewellyn E, Chen J, Olinares PDB, Brewer J, Chait BT, Campbell EA, Darst SA. Structural basis for transcription complex disruption by the Mfd translocase. eLife 2021; 10:62117. [PMID: 33480355 PMCID: PMC7864632 DOI: 10.7554/elife.62117] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 01/21/2021] [Indexed: 12/30/2022] Open
Abstract
Transcription-coupled repair (TCR) is a sub-pathway of nucleotide excision repair (NER) that preferentially removes lesions from the template-strand (t-strand) that stall RNA polymerase (RNAP) elongation complexes (ECs). Mfd mediates TCR in bacteria by removing the stalled RNAP concealing the lesion and recruiting Uvr(A)BC. We used cryo-electron microscopy to visualize Mfd engaging with a stalled EC and attempting to dislodge the RNAP. We visualized seven distinct Mfd-EC complexes in both ATP and ADP-bound states. The structures explain how Mfd is remodeled from its repressed conformation, how the UvrA-interacting surface of Mfd is hidden during most of the remodeling process to prevent premature engagement with the NER pathway, how Mfd alters the RNAP conformation to facilitate disassembly, and how Mfd forms a processive translocation complex after dislodging the RNAP. Our results reveal an elaborate mechanism for how Mfd kinetically discriminates paused from stalled ECs and disassembles stalled ECs to initiate TCR.
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Affiliation(s)
- Jin Young Kang
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
| | - Eliza Llewellyn
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
| | - James Chen
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
| | - Paul Dominic B Olinares
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
| | - Joshua Brewer
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
| | - Elizabeth A Campbell
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
| | - Seth A Darst
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, United States
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9
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Brugger C, Zhang C, Suhanovsky MM, Kim DD, Sinclair AN, Lyumkis D, Deaconescu AM. Molecular determinants for dsDNA translocation by the transcription-repair coupling and evolvability factor Mfd. Nat Commun 2020; 11:3740. [PMID: 32719356 PMCID: PMC7385628 DOI: 10.1038/s41467-020-17457-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 07/01/2020] [Indexed: 11/15/2022] Open
Abstract
Mfd couples transcription to nucleotide excision repair, and acts on RNA polymerases when elongation is impeded. Depending on impediment severity, this action results in either transcription termination or elongation rescue, which rely on ATP-dependent Mfd translocation on DNA. Due to its role in antibiotic resistance, Mfd is also emerging as a prime target for developing anti-evolution drugs. Here we report the structure of DNA-bound Mfd, which reveals large DNA-induced structural changes that are linked to the active site via ATPase motif VI. These changes relieve autoinhibitory contacts between the N- and C-termini and unmask UvrA recognition determinants. We also demonstrate that translocation relies on a threonine in motif Ic, widely conserved in translocases, and a family-specific histidine near motif IVa, reminiscent of the “arginine clamp” of RNA helicases. Thus, Mfd employs a mode of DNA recognition that at its core is common to ss/ds translocases that act on DNA or RNA. Transcription-repair coupling factors (TRCFs) are large ATPases that mediate the preferential repair of the transcribed DNA strand. Here the authors reveal the cryo-EM structure of DNA-bound Mfd, the bacterial TRCF, and provide molecular insights into its mode of action.
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Affiliation(s)
- Christiane Brugger
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02903, USA
| | - Cheng Zhang
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92093, USA
| | - Margaret M Suhanovsky
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02903, USA
| | - David D Kim
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02903, USA
| | - Amy N Sinclair
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02903, USA
| | - Dmitry Lyumkis
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, 92093, USA.,Department of Computational and Structural Biology, The Scripps Research Institute, La Jolla, CA, 92093, USA
| | - Alexandra M Deaconescu
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02903, USA.
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10
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Ho HN, van Oijen AM, Ghodke H. Single-molecule imaging reveals molecular coupling between transcription and DNA repair machinery in live cells. Nat Commun 2020; 11:1478. [PMID: 32198374 PMCID: PMC7083905 DOI: 10.1038/s41467-020-15182-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 02/23/2020] [Indexed: 01/20/2023] Open
Abstract
The Escherichia coli transcription-repair coupling factor Mfd displaces stalled RNA polymerase and delivers the stall site to the nucleotide excision repair factors UvrAB for damage detection. Whether this handoff from RNA polymerase to UvrA occurs via the Mfd-UvrA2-UvrB complex or alternate reaction intermediates in cells remains unclear. Here, we visualise Mfd in actively growing cells and determine the catalytic requirements for faithful recruitment of nucleotide excision repair proteins. We find that ATP hydrolysis by UvrA governs formation and disassembly of the Mfd-UvrA2 complex. Further, Mfd-UvrA2-UvrB complexes formed by UvrB mutants deficient in DNA loading and damage recognition are impaired in successful handoff. Our single-molecule dissection of interactions of Mfd with its partner proteins inside live cells shows that the dissociation of Mfd is tightly coupled to successful loading of UvrB, providing a mechanism via which loading of UvrB occurs in a strand-specific manner.
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Affiliation(s)
- Han Ngoc Ho
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia
| | - Harshad Ghodke
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia.
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia.
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11
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Roberts JW. Mechanisms of Bacterial Transcription Termination. J Mol Biol 2019; 431:4030-4039. [PMID: 30978344 DOI: 10.1016/j.jmb.2019.04.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 03/28/2019] [Accepted: 04/02/2019] [Indexed: 01/28/2023]
Abstract
Bacterial transcription termination, described mostly for Escherichia coli, occurs in three recognized ways: intrinsic termination, an activity only of the core RNAP enzyme and transcript sequences that encode an RNA hairpin and terminal uridine-rich segment; termination by the enzyme Rho, an ATP-dependent RNA translocase that releases RNA by forcing uncharacterized structural changes in the elongating complex; and Mfd-dependent termination, the activity of an ATP-dependent DNA translocase that is thought to dissociate the elongation complex by exerting torque on a stalled RNAP. Intrinsic termination can be described in terms of the nucleic acid movements in the process, whereas the enzymatic mechanisms have been illuminated importantly by definitive structural and biochemical analysis of their activity.
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Affiliation(s)
- Jeffrey W Roberts
- Department of Molecular Biology and Genetics, Biotechnology Building, Cornell University, Ithaca, NY 14853, USA.
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12
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Rho-dependent transcription termination in bacteria recycles RNA polymerases stalled at DNA lesions. Nat Commun 2019; 10:1207. [PMID: 30872584 PMCID: PMC6418286 DOI: 10.1038/s41467-019-09146-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 02/14/2019] [Indexed: 01/25/2023] Open
Abstract
In bacteria, transcription-coupled repair of DNA lesions initiates after the Mfd protein removes RNA polymerases (RNAPs) stalled at the lesions. The bacterial RNA helicase, Rho, is a transcription termination protein that dislodges the elongation complexes. Here, we show that Rho dislodges the stalled RNAPs at DNA lesions. Strains defective in both Rho and Mfd are susceptible to DNA-damaging agents and are inefficient in repairing or propagating UV-damaged DNA. In vitro transcription assays show that Rho dissociates the stalled elongation complexes at the DNA lesions. We conclude that Rho-dependent termination recycles stalled RNAPs, which might facilitate DNA repair and other DNA-dependent processes essential for bacterial cell survival. We surmise that Rho might compete with, or augment, the Mfd function. In bacteria, the Rho protein dislodges elongation complexes to terminate transcription, and the Mfd protein removes RNA polymerases (RNAPs) stalled at DNA lesions. Here, Jain et al. show that Rho also dissociates stalled RNAPs at DNA lesions, which may facilitate DNA repair and other DNA-dependent processes.
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13
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Le TT, Yang Y, Tan C, Suhanovsky MM, Fulbright RM, Inman JT, Li M, Lee J, Perelman S, Roberts JW, Deaconescu AM, Wang MD. Mfd Dynamically Regulates Transcription via a Release and Catch-Up Mechanism. Cell 2017; 172:344-357.e15. [PMID: 29224782 DOI: 10.1016/j.cell.2017.11.017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/21/2017] [Accepted: 11/09/2017] [Indexed: 11/25/2022]
Abstract
The bacterial Mfd ATPase is increasingly recognized as a general transcription factor that participates in the resolution of transcription conflicts with other processes/roadblocks. This function stems from Mfd's ability to preferentially act on stalled RNA polymerases (RNAPs). However, the mechanism underlying this preference and the subsequent coordination between Mfd and RNAP have remained elusive. Here, using a novel real-time translocase assay, we unexpectedly discovered that Mfd translocates autonomously on DNA. The speed and processivity of Mfd dictate a "release and catch-up" mechanism to efficiently patrol DNA for frequently stalled RNAPs. Furthermore, we showed that Mfd prevents RNAP backtracking or rescues a severely backtracked RNAP, allowing RNAP to overcome stronger obstacles. However, if an obstacle's resistance is excessive, Mfd dissociates the RNAP, clearing the DNA for other processes. These findings demonstrate a remarkably delicate coordination between Mfd and RNAP, allowing efficient targeting and recycling of Mfd and expedient conflict resolution.
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Affiliation(s)
- Tung T Le
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Yi Yang
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Chuang Tan
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Margaret M Suhanovsky
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02903, USA
| | | | - James T Inman
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Ming Li
- Department of Chemistry, Cornell University, Ithaca, NY 14853, USA
| | - Jaeyoon Lee
- Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA
| | - Sarah Perelman
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02903, USA
| | - Jeffrey W Roberts
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Alexandra M Deaconescu
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02903, USA
| | - Michelle D Wang
- Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA; Physics Department & LASSP, Cornell University, Ithaca, NY 14853, USA.
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14
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Toliusis P, Zaremba M, Silanskas A, Szczelkun MD, Siksnys V. CgII cleaves DNA using a mechanism distinct from other ATP-dependent restriction endonucleases. Nucleic Acids Res 2017; 45:8435-8447. [PMID: 28854738 PMCID: PMC5737866 DOI: 10.1093/nar/gkx580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/28/2017] [Indexed: 01/10/2023] Open
Abstract
The restriction endonuclease CglI from Corynebacterium glutamicum recognizes an asymmetric 5′-GCCGC-3′ site and cleaves the DNA 7 and 6/7 nucleotides downstream on the top and bottom DNA strands, respectively, in an NTP-hydrolysis dependent reaction. CglI is composed of two different proteins: an endonuclease (R.CglI) and a DEAD-family helicase-like ATPase (H.CglI). These subunits form a heterotetrameric complex with R2H2 stoichiometry. However, the R2H2·CglI complex has only one nuclease active site sufficient to cut one DNA strand suggesting that two complexes are required to introduce a double strand break. Here, we report studies to evaluate the DNA cleavage mechanism of CglI. Using one- and two-site circular DNA substrates we show that CglI does not require two sites on the same DNA for optimal catalytic activity. However, one-site linear DNA is a poor substrate, supporting a mechanism where CglI complexes must communicate along the one-dimensional DNA contour before cleavage is activated. Based on experimental data, we propose that adenosine triphosphate (ATP) hydrolysis by CglI produces translocation on DNA preferentially in a downstream direction from the target, although upstream translocation is also possible. Our results are consistent with a mechanism of CglI action that is distinct from that of other ATP-dependent restriction-modification enzymes.
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Affiliation(s)
- Paulius Toliusis
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Mindaugas Zaremba
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Arunas Silanskas
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
| | - Mark D Szczelkun
- DNA-Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK
| | - Virginijus Siksnys
- Department of Protein-DNA Interactions, Institute of Biotechnology, Vilnius University, Sauletekio al. 7, LT-10257, Vilnius, Lithuania
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15
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Sanders K, Lin CL, Smith AJ, Cronin N, Fisher G, Eftychidis V, McGlynn P, Savery NJ, Wigley DB, Dillingham MS. The structure and function of an RNA polymerase interaction domain in the PcrA/UvrD helicase. Nucleic Acids Res 2017; 45:3875-3887. [PMID: 28160601 PMCID: PMC5397179 DOI: 10.1093/nar/gkx074] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 01/25/2017] [Indexed: 11/14/2022] Open
Abstract
The PcrA/UvrD helicase functions in multiple pathways that promote bacterial genome stability including the suppression of conflicts between replication and transcription and facilitating the repair of transcribed DNA. The reported ability of PcrA/UvrD to bind and backtrack RNA polymerase (1,2) might be relevant to these functions, but the structural basis for this activity is poorly understood. In this work, we define a minimal RNA polymerase interaction domain in PcrA, and report its crystal structure at 1.5 Å resolution. The domain adopts a Tudor-like fold that is similar to other RNA polymerase interaction domains, including that of the prototype transcription-repair coupling factor Mfd. Removal or mutation of the interaction domain reduces the ability of PcrA/UvrD to interact with and to remodel RNA polymerase complexes in vitro. The implications of this work for our understanding of the role of PcrA/UvrD at the interface of DNA replication, transcription and repair are discussed.
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Affiliation(s)
- Kelly Sanders
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Chia-Liang Lin
- Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK and Section of Structural Biology, Department of Medicine, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Abigail J Smith
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Nora Cronin
- Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK and Section of Structural Biology, Department of Medicine, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Gemma Fisher
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | | | - Peter McGlynn
- Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK
| | - Nigel J Savery
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Dale B Wigley
- Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK and Section of Structural Biology, Department of Medicine, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Mark S Dillingham
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
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16
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Mustaev A, Roberts J, Gottesman M. Transcription elongation. Transcription 2017; 8:150-161. [PMID: 28301288 PMCID: PMC5501382 DOI: 10.1080/21541264.2017.1289294] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/25/2017] [Accepted: 01/26/2017] [Indexed: 12/23/2022] Open
Abstract
This review is focused on recent progress in understanding how Escherichia coli RNAP polymerase translocates along the DNA template and the factors that affect this movement. We discuss the fundamental aspects of RNAP translocation, template signals that influence forward or backward movement, and host or phage factors that modulate translocation.
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Affiliation(s)
- Arkady Mustaev
- PHRI Center, NJMS, Rutgers, The State University of New Jersey, Newark, NJ, USA
| | - Jeffrey Roberts
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Max Gottesman
- Department of Microbiology & Immunology, Columbia University Medical Center, New York, NY, USA
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17
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Selby CP. Mfd Protein and Transcription-Repair Coupling in Escherichia coli. Photochem Photobiol 2017; 93:280-295. [PMID: 27864884 DOI: 10.1111/php.12675] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/18/2016] [Indexed: 01/30/2023]
Abstract
In 1989, transcription-repair coupling (TRC) was first described in Escherichia coli, as the transcription-dependent, preferential nucleotide excision repair (NER) of UV photoproducts located in the template DNA strand. This finding led to pioneering biochemical studies of TRC in the laboratory of Professor Aziz Sancar, where, at the time, major contributions were being made toward understanding the roles of the UvrA, UvrB and UvrC proteins in NER. When the repair studies were extended to TRC, template but not coding strand lesions were found to block RNA polymerase (RNAP) in vitro, and unexpectedly, the blocked RNAP inhibited NER. A transcription-repair coupling factor, also called Mfd protein, was found to remove the blocked RNAP, deliver the repair enzyme to the lesion and thereby mediate more rapid repair of the transcription-blocking lesion compared with lesions elsewhere. Structural and functional analyses of Mfd protein revealed helicase motifs responsible for ATP hydrolysis and DNA binding, and regions that interact with RNAP and UvrA. These and additional studies provided a basis upon which other investigators, in following decades, have characterized fascinating and unexpected structural and mechanistic features of Mfd, revealed the possible existence of additional pathways of TRC and discovered additional roles of Mfd in the cell.
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Affiliation(s)
- Christopher P Selby
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, NC
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18
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Abstract
The known diversity of metabolic strategies and physiological adaptations of archaeal species to extreme environments is extraordinary. Accurate and responsive mechanisms to ensure that gene expression patterns match the needs of the cell necessitate regulatory strategies that control the activities and output of the archaeal transcription apparatus. Archaea are reliant on a single RNA polymerase for all transcription, and many of the known regulatory mechanisms employed for archaeal transcription mimic strategies also employed for eukaryotic and bacterial species. Novel mechanisms of transcription regulation have become apparent by increasingly sophisticated in vivo and in vitro investigations of archaeal species. This review emphasizes recent progress in understanding archaeal transcription regulatory mechanisms and highlights insights gained from studies of the influence of archaeal chromatin on transcription.
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19
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Abstract
Bacteria lack subcellular compartments and harbor a single RNA polymerase that synthesizes both structural and protein-coding RNAs, which are cotranscriptionally processed by distinct pathways. Nascent rRNAs fold into elaborate secondary structures and associate with ribosomal proteins, whereas nascent mRNAs are translated by ribosomes. During elongation, nucleic acid signals and regulatory proteins modulate concurrent RNA-processing events, instruct RNA polymerase where to pause and terminate transcription, or act as roadblocks to the moving enzyme. Communications among complexes that carry out transcription, translation, repair, and other cellular processes ensure timely execution of the gene expression program and survival under conditions of stress. This network is maintained by auxiliary proteins that act as bridges between RNA polymerase, ribosome, and repair enzymes, blurring boundaries between separate information-processing steps and making assignments of unique regulatory functions meaningless. Understanding the regulation of transcript elongation thus requires genome-wide approaches, which confirm known and reveal new regulatory connections.
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Affiliation(s)
| | - Irina Artsimovitch
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210;
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20
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Chen SH, Byrne RT, Wood EA, Cox MM. Escherichia coli radD (yejH) gene: a novel function involved in radiation resistance and double-strand break repair. Mol Microbiol 2015; 95:754-68. [PMID: 25425430 DOI: 10.1111/mmi.12885] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2014] [Indexed: 11/28/2022]
Abstract
A transposon insertion screen implicated the yejH gene in the repair of ionizing radiation-induced damage. The yejH gene, which exhibits significant homology to the human transcription-coupled DNA repair gene XPB, is involved in the repair of double-strand DNA breaks. Deletion of yejH significantly sensitized cells to agents that cause double-strand breaks (ionizing radiation, UV radiation, ciprofloxacin). In addition, deletion of both yejH and radA hypersensitized the cells to ionizing radiation, UV and ciprofloxacin damage, indicating that these two genes have complementary repair functions. The ΔyejH ΔradA double deletion also showed a substantial decline in viability following an induced double-strand DNA break, of a magnitude comparable with the defect measured when the recA, recB, recG or priA genes are deleted. The ATPase activity and C-terminal zinc finger motif of yejH play an important role in its repair function, as targeted mutant alleles of yejH did not rescue sensitivity. We propose that yejH be renamed radD, reflecting its role in the DNA repair of radiation damage.
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Affiliation(s)
- Stefanie H Chen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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21
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Kamarthapu V, Nudler E. Rethinking transcription coupled DNA repair. Curr Opin Microbiol 2015; 24:15-20. [PMID: 25596348 DOI: 10.1016/j.mib.2014.12.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/22/2014] [Accepted: 12/30/2014] [Indexed: 11/26/2022]
Abstract
Nucleotide excision repair (NER) is an evolutionarily conserved, multistep process that can detect a wide variety of DNA lesions. Transcription coupled repair (TCR) is a subpathway of NER that repairs the transcribed DNA strand faster than the rest of the genome. RNA polymerase (RNAP) stalled at DNA lesions mediates the recruitment of NER enzymes to the damage site. In this review we focus on a newly identified bacterial TCR pathway in which the NER enzyme UvrD, in conjunction with NusA, plays a major role in initiating the repair process. We discuss the tradeoff between the new and conventional models of TCR, how and when each pathway operates to repair DNA damage, and the necessity of pervasive transcription in maintaining genome integrity.
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Affiliation(s)
- Venu Kamarthapu
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA; Howard Hughes Medical Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Evgeny Nudler
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA; Howard Hughes Medical Institute, New York University School of Medicine, New York, NY 10016, USA.
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22
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Deaconescu AM. RNA polymerase between lesion bypass and DNA repair. Cell Mol Life Sci 2013; 70:4495-509. [PMID: 23807206 PMCID: PMC11113250 DOI: 10.1007/s00018-013-1384-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 05/13/2013] [Accepted: 05/23/2013] [Indexed: 11/29/2022]
Abstract
DNA damage leads to heritable changes in the genome via DNA replication. However, as the DNA helix is the site of numerous other transactions, notably transcription, DNA damage can have diverse repercussions on cellular physiology. In particular, DNA lesions have distinct effects on the passage of transcribing RNA polymerases, from easy bypass to almost complete block of transcription elongation. The fate of the RNA polymerase positioned at a lesion is largely determined by whether the lesion is structurally subtle and can be accommodated and eventually bypassed, or bulky, structurally distorting and requiring remodeling/complete dissociation of the transcription elongation complex, excision, and repair. Here we review cellular responses to DNA damage that involve RNA polymerases with a focus on bacterial transcription-coupled nucleotide excision repair and lesion bypass via transcriptional mutagenesis. Emphasis is placed on the explosion of new structural information on RNA polymerases and relevant DNA repair factors and the mechanistic models derived from it.
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Affiliation(s)
- Alexandra M Deaconescu
- Rosenstiel Basic Medical Sciences Research Center, Brandeis University, 415 South St., MS029, Waltham, MA, 02454, USA,
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23
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Deaconescu AM, Artsimovitch I, Grigorieff N. Interplay of DNA repair with transcription: from structures to mechanisms. Trends Biochem Sci 2012; 37:543-52. [PMID: 23084398 DOI: 10.1016/j.tibs.2012.09.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 09/10/2012] [Accepted: 09/14/2012] [Indexed: 01/29/2023]
Abstract
Many DNA transactions are crucial for maintaining genomic integrity and faithful transfer of genetic information but remain poorly understood. An example is the interplay between nucleotide excision repair (NER) and transcription, also known as transcription-coupled DNA repair (TCR). Discovered decades ago, the mechanisms for TCR have remained elusive, not in small part due to the scarcity of structural studies of key players. Here we summarize recent structural information on NER/TCR factors, focusing on bacterial systems, and integrate it with existing genetic, biochemical, and biophysical data to delineate the mechanisms at play. We also review emerging, alternative modalities for recruitment of NER proteins to DNA lesions.
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Affiliation(s)
- Alexandra M Deaconescu
- Howard Hughes Medical Institute, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, 415 South St., MS 029, Waltham, MA 02454, USA.
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