1
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Shuman S. RNA Repair: Hiding in Plain Sight. Annu Rev Genet 2023; 57:461-489. [PMID: 37722686 DOI: 10.1146/annurev-genet-071719-021856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
Enzymes that phosphorylate, dephosphorylate, and ligate RNA 5' and 3' ends were discovered more than half a century ago and were eventually shown to repair purposeful site-specific endonucleolytic breaks in the RNA phosphodiester backbone. The pace of discovery and characterization of new candidate RNA repair activities in taxa from all phylogenetic domains greatly exceeds our understanding of the biological pathways in which they act. The key questions anent RNA break repair in vivo are (a) identifying the triggers, agents, and targets of RNA cleavage and (b) determining whether RNA repair results in restoration of the original RNA, modification of the RNA (by loss or gain at the ends), or rearrangements of the broken RNA segments (i.e., RNA recombination). This review provides a perspective on the discovery, mechanisms, and physiology of purposeful RNA break repair, highlighting exemplary repair pathways (e.g., tRNA restriction-repair and tRNA splicing) for which genetics has figured prominently in their elucidation.
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Affiliation(s)
- Stewart Shuman
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA;
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2
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Moncan M, Rakhsh-Khorshid H, Eriksson LA, Samali A, Gorman AM. Insights into the structure and function of the RNA ligase RtcB. Cell Mol Life Sci 2023; 80:352. [PMID: 37935993 PMCID: PMC10630183 DOI: 10.1007/s00018-023-05001-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/19/2023] [Accepted: 10/11/2023] [Indexed: 11/09/2023]
Abstract
To be functional, some RNAs require a processing step involving splicing events. Each splicing event necessitates an RNA ligation step. RNA ligation is a process that can be achieved with various intermediaries such as self-catalysing RNAs, 5'-3' and 3'-5' RNA ligases. While several types of RNA ligation mechanisms occur in human, RtcB is the only 3'-5' RNA ligase identified in human cells to date. RtcB RNA ligation activity is well known to be essential for the splicing of XBP1, an essential transcription factor of the unfolded protein response; as well as for the maturation of specific intron-containing tRNAs. As such, RtcB is a core factor in protein synthesis and homeostasis. Taking advantage of the high homology between RtcB orthologues in archaea, bacteria and eukaryotes, this review will provide an introduction to the structure of RtcB and the mechanism of 3'-5' RNA ligation. This analysis is followed by a description of the mechanisms regulating RtcB activity and localisation, its known partners and its various functions from bacteria to human with a specific focus on human cancer.
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Affiliation(s)
- Matthieu Moncan
- Apoptosis Research Centre, University of Galway, Galway, Ireland
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Hassan Rakhsh-Khorshid
- Apoptosis Research Centre, University of Galway, Galway, Ireland
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Leif A Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden
| | - Afshin Samali
- Apoptosis Research Centre, University of Galway, Galway, Ireland
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
- CÚRAM SFI Research Centre for Medical Devices, University of Galway, Galway, Ireland
| | - Adrienne M Gorman
- Apoptosis Research Centre, University of Galway, Galway, Ireland.
- School of Biological and Chemical Sciences, University of Galway, Galway, Ireland.
- CÚRAM SFI Research Centre for Medical Devices, University of Galway, Galway, Ireland.
- Biomedical Sciences, Upper Newcastle, University of Galway, Galway, H91 W2TY, Ireland.
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3
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Jacewicz A, Dantuluri S, Shuman S. Structures of RNA ligase RtcB in complexes with divalent cations and GTP. RNA (NEW YORK, N.Y.) 2022; 28:1509-1518. [PMID: 36130078 PMCID: PMC9745838 DOI: 10.1261/rna.079327.122] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/02/2022] [Indexed: 06/15/2023]
Abstract
Pyrococcus horikoshii (Pho) RtcB exemplifies a family of binuclear transition metal- and GTP-dependent RNA ligases that join 3'-phosphate and 5'-OH ends via RtcB-(histidinyl-N)-GMP and RNA3'pp5'G intermediates. We find that guanylylation of PhoRtcB is optimal with manganese and less effective with cobalt and nickel. Zinc and copper are inactive and potently inhibit manganese-dependent guanylylation. We report crystal structures of PhoRtcB in complexes with GTP and permissive (Mn, Co, Ni) or inhibitory (Zn, Cu) metals. Zinc and copper occupy the M1 and M2 sites adjacent to the GTP phosphates, as do manganese, cobalt, and nickel. The identity/positions of enzymic ligands for M1 (His234, His329, Cys98) and M2 (Cys98, Asp95, His203) are the same for permissive and inhibitory metals. The differences pertain to: (i) the coordination geometries and phosphate contacts of the metals; and (ii) the orientation of the His404 nucleophile with respect to the GTP α-phosphate and pyrophosphate leaving group. M2 metal coordination geometry correlates with metal cofactor activity, whereby inhibitory Zn2 and Cu2 assume a tetrahedral configuration and contact only the GTP γ-phosphate, whereas Mn2, Co2, and Ni2 coordination complexes are pentahedral and contact the β- and γ-phosphates. The His404-Nε-Pα-O(α-β) angle is closer to apical in Mn (179°), Co (171°), and Ni (169°) structures than in Zn (160°) and Cu (155°) structures. The octahedral Mn1 geometry in our RtcB•GTP•Mn2+ structure, in which Mn1 contacts α-, β-, and γ-phosphates, transitions to a tetrahedral configuration after formation of RtcB•(His404)-GMP•Mn2+ and departure of pyrophosphate.
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Affiliation(s)
- Agata Jacewicz
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Swathi Dantuluri
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Stewart Shuman
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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4
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Sequential rescue and repair of stalled and damaged ribosome by bacterial PrfH and RtcB. Proc Natl Acad Sci U S A 2022; 119:e2202464119. [PMID: 35858322 PMCID: PMC9304027 DOI: 10.1073/pnas.2202464119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
RtcB is involved in transfer RNA (tRNA) splicing in archaeal and eukaryotic organisms. However, most RtcBs are found in bacteria, whose tRNAs have no introns. Because tRNAs are the substrates of archaeal and eukaryotic RtcB, it is assumed that bacterial RtcBs are for repair of damaged tRNAs. Here, we show that a subset of bacterial RtcB, denoted RtcB2 herein, specifically repair ribosomal damage in the decoding center. To access the damage site for repair, however, the damaged 70S ribosome needs to be dismantled first, and this is accomplished by bacterial PrfH. Peptide-release assays revealed that PrfH is only active with the damaged 70S ribosome but not with the intact one. A 2.55-Å cryo-electron microscopy structure of PrfH in complex with the damaged 70S ribosome provides molecular insight into PrfH discriminating between the damaged and the intact ribosomes via specific recognition of the cleaved 3'-terminal nucleotide. RNA repair assays demonstrated that RtcB2 efficiently repairs the damaged 30S ribosomal subunit but not the damaged tRNAs. Cell-based assays showed that the RtcB2-PrfH pair reverse the damage inflicted by ribosome-specific ribotoxins in vivo. Thus, our combined biochemical, structural, and cell-based studies have uncovered a bacterial defense system specifically evolved to reverse the lethal ribosomal damage in the decoding center for cell survival.
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5
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Gerber JL, Köhler S, Peschek J. Eukaryotic tRNA splicing - one goal, two strategies, many players. Biol Chem 2022; 403:765-778. [PMID: 35621519 DOI: 10.1515/hsz-2021-0402] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 05/10/2022] [Indexed: 12/28/2022]
Abstract
Transfer RNAs (tRNAs) are transcribed as precursor molecules that undergo several maturation steps before becoming functional for protein synthesis. One such processing mechanism is the enzyme-catalysed splicing of intron-containing pre-tRNAs. Eukaryotic tRNA splicing is an essential process since intron-containing tRNAs cannot fulfil their canonical function at the ribosome. Splicing of pre-tRNAs occurs in two steps: The introns are first excised by a tRNA-splicing endonuclease and the exons are subsequently sealed by an RNA ligase. An intriguing complexity has emerged from newly identified tRNA splicing factors and their interplay with other RNA processing pathways during the past few years. This review summarises our current understanding of eukaryotic tRNA splicing and the underlying enzyme machinery. We highlight recent structural advances and how they have shaped our mechanistic understanding of tRNA splicing in eukaryotic cells. A special focus lies on biochemically distinct strategies for exon-exon ligation in fungi versus metazoans.
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Affiliation(s)
- Janina L Gerber
- Biochemistry Center (BZH), Heidelberg University, D-69120 Heidelberg, Germany
| | - Sandra Köhler
- Biochemistry Center (BZH), Heidelberg University, D-69120 Heidelberg, Germany
| | - Jirka Peschek
- Biochemistry Center (BZH), Heidelberg University, D-69120 Heidelberg, Germany
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6
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Kroupova A, Ackle F, Asanović I, Weitzer S, Boneberg FM, Faini M, Leitner A, Chui A, Aebersold R, Martinez J, Jinek M. Molecular architecture of the human tRNA ligase complex. eLife 2021; 10:e71656. [PMID: 34854379 PMCID: PMC8668186 DOI: 10.7554/elife.71656] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 12/01/2021] [Indexed: 01/23/2023] Open
Abstract
RtcB enzymes are RNA ligases that play essential roles in tRNA splicing, unfolded protein response, and RNA repair. In metazoa, RtcB functions as part of a five-subunit tRNA ligase complex (tRNA-LC) along with Ddx1, Cgi-99, Fam98B, and Ashwin. The human tRNA-LC or its individual subunits have been implicated in additional cellular processes including microRNA maturation, viral replication, DNA double-strand break repair, and mRNA transport. Here, we present a biochemical analysis of the inter-subunit interactions within the human tRNA-LC along with crystal structures of the catalytic subunit RTCB and the N-terminal domain of CGI-99. We show that the core of the human tRNA-LC is assembled from RTCB and the C-terminal alpha-helical regions of DDX1, CGI-99, and FAM98B, all of which are required for complex integrity. The N-terminal domain of CGI-99 displays structural homology to calponin-homology domains, and CGI-99 and FAM98B associate via their N-terminal domains to form a stable subcomplex. The crystal structure of GMP-bound RTCB reveals divalent metal coordination geometry in the active site, providing insights into its catalytic mechanism. Collectively, these findings shed light on the molecular architecture and mechanism of the human tRNA ligase complex and provide a structural framework for understanding its functions in cellular RNA metabolism.
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Affiliation(s)
- Alena Kroupova
- Department of Biochemistry, University of ZurichZurichSwitzerland
| | - Fabian Ackle
- Department of Biochemistry, University of ZurichZurichSwitzerland
| | - Igor Asanović
- Max Perutz Labs, Vienna BioCenter (VBC)ViennaAustria
| | | | | | - Marco Faini
- Department of Biology, Institute of Molecular Systems Biology, ETH ZurichZurichSwitzerland
| | - Alexander Leitner
- Department of Biology, Institute of Molecular Systems Biology, ETH ZurichZurichSwitzerland
| | - Alessia Chui
- Department of Biochemistry, University of ZurichZurichSwitzerland
| | - Ruedi Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH ZurichZurichSwitzerland
| | | | - Martin Jinek
- Department of Biochemistry, University of ZurichZurichSwitzerland
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7
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Banerjee A, Goldgur Y, Shuman S. Structure of 3'-PO 4/5'-OH RNA ligase RtcB in complex with a 5'-OH oligonucleotide. RNA (NEW YORK, N.Y.) 2021; 27:rna.078692.121. [PMID: 33619169 PMCID: PMC8051266 DOI: 10.1261/rna.078692.121] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 02/21/2021] [Indexed: 06/12/2023]
Abstract
RtcB enzymes comprise a widely distributed family of manganese- and GTP-dependent RNA repair enzymes that join 2',3'-cyclic phosphate ends to 5'-OH ends via RtcB-(histidinyl-N)-GMP, RNA 3'-phosphate, and RNA3'pp5'G intermediates. RtcB can ligate either 5'-OH RNA or 5'-OH DNA strands in vitro. The nucleic acid contacts of RtcB are uncharted. Here we report a 2.7 Å crystal structure of Pyrococcus horikoshii RtcB in complex with a 6-mer 5'-OH DNA oligonucleotide HOA1pT2pG3pT4pC5pC6, which reveals enzymic contacts of Asn202 to the terminal 5'-OH nucleophile; Arg238 to the A1pT2 and T2pG3 phosphates; Arg190 and Gln194 to the T2pG3 phosphate; and an Arg190 π-cation interaction with the G3 nucleobase. The structural insights affirm functional studies of E. coli RtcB that implicated the conserved counterpart of Arg238 in engagement of the 5'-OH strand for ligation. The essential active site Cys98 that coordinates two manganese ions is oxidized to cysteine sulfonic acid in our structure, raising the prospect that RtcB activity might be sensitive to modulation during oxidative stress.
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8
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Berk C, Wang Y, Laski A, Tsagkris S, Hall J. Ligation of 2', 3'-cyclic phosphate RNAs for the identification of microRNA binding sites. FEBS Lett 2020; 595:230-240. [PMID: 33113149 PMCID: PMC7894349 DOI: 10.1002/1873-3468.13976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/27/2020] [Accepted: 10/08/2020] [Indexed: 11/21/2022]
Abstract
Identifying the targetome of a microRNA is key for understanding its functions. Cross‐linking and immunoprecipitation (CLIP) methods capture native miRNA‐mRNA interactions in cells. Some of these methods yield small amounts of chimeric miRNA‐mRNA sequences via ligation of 5′‐phosphorylated RNAs produced during the protocol. Here, we introduce chemically synthesized microRNAs (miRNAs) bearing 2′‐, 3′‐cyclic phosphate groups, as part of a new CLIP method that does not require 5′‐phosphorylation for ligation. We show in a system that models miRNAs bound to their targets, that addition of recombinant bacterial ligase RtcB increases ligation efficiency, and that the transformation proceeds via a 3′‐phosphate intermediate. By optimizing the chemistry underlying ligation, we provide the basis for an improved method to identify miRNA targetomes.
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Affiliation(s)
- Christian Berk
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
| | - Yuluan Wang
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
| | - Artur Laski
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
| | - Stylianos Tsagkris
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
| | - Jonathan Hall
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Switzerland
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9
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Banerjee A, Goldgur Y, Schwer B, Shuman S. Atomic structures of the RNA end-healing 5'-OH kinase and 2',3'-cyclic phosphodiesterase domains of fungal tRNA ligase: conformational switches in the kinase upon binding of the GTP phosphate donor. Nucleic Acids Res 2020; 47:11826-11838. [PMID: 31722405 PMCID: PMC7145591 DOI: 10.1093/nar/gkz1049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/16/2019] [Accepted: 11/07/2019] [Indexed: 01/17/2023] Open
Abstract
Fungal tRNA ligase (Trl1) rectifies RNA breaks with 2′,3′-cyclic-PO4 and 5′-OH termini. Trl1 consists of three catalytic modules: an N-terminal ligase (LIG) domain; a central polynucleotide kinase (KIN) domain; and a C-terminal cyclic phosphodiesterase (CPD) domain. Trl1 enzymes found in all human fungal pathogens are untapped targets for antifungal drug discovery. Here we report a 1.9 Å crystal structure of Trl1 KIN-CPD from the pathogenic fungus Candida albicans, which adopts an extended conformation in which separate KIN and CPD domains are connected by an unstructured linker. CPD belongs to the 2H phosphotransferase superfamily by dint of its conserved central concave β sheet and interactions of its dual HxT motif histidines and threonines with phosphate in the active site. Additional active site motifs conserved among the fungal CPD clade of 2H enzymes are identified. We present structures of the Candida Trl1 KIN domain at 1.5 to 2.0 Å resolution—as apoenzyme and in complexes with GTP•Mg2+, IDP•PO4, and dGDP•PO4—that highlight conformational switches in the G-loop (which recognizes the guanine base) and lid-loop (poised over the nucleotide phosphates) that accompany nucleotide binding.
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Affiliation(s)
- Ankan Banerjee
- Molecular Biology Program, Sloan-Kettering Institute, New York, NY 10065, USA
| | - Yehuda Goldgur
- Structural Biology Program, Sloan-Kettering Institute, New York, NY 10065, USA
| | - Beate Schwer
- Microbiology and Immunology Department, Weill Cornell Medical College, New York, NY 10065, USA
| | - Stewart Shuman
- Molecular Biology Program, Sloan-Kettering Institute, New York, NY 10065, USA
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10
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Manwar MR, Shao C, Shi X, Wang J, Lin Q, Tong Y, Kang Y, Yu J. The bacterial RNA ligase RtcB accelerates the repair process of fragmented rRNA upon releasing the antibiotic stress. SCIENCE CHINA. LIFE SCIENCES 2020; 63:251-258. [PMID: 31250189 DOI: 10.1007/s11427-018-9405-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 10/10/2018] [Indexed: 12/23/2022]
Abstract
RtcB, a highly conserved RNA ligase, is found in all three domains of life, and demonstrated to be an essential tRNA splicing component in archaea and metazoans. However, the biological functions of RtcB in bacteria, where there is no splicing, remains to be clarified. We first performed bioinformatics analysis which revealed highly conserved structures and presumably conserved functions of RtcB in bacteria. However, its orthologs only occur in ∼ 0.5% of bacterial species across diverse phyla with significant signals of frequent horizontal transfer, highlighting its non-essential role in bacteria. Next, by constructing an rtcB-knockout strain, we find that the removal of antibiotic stress induces a significant impact on rtcB expression in wild-type strain, and furthermore the depletion of RtcB (ARtcB strain) delays the recovery process. Our transcriptomic analysis, comprising the 3'-end labeling of RNAs, highlights a significant increase in unmapped reads and cleaved rRNAs in the Δ RtcB strain, particularly during recovery. Our observations suggest that the conserved RNA ligase RtcB, repairs damaged rRNAs following stress, which potentially saves energy and accelerates recovery of its host. We propose that acquisition of RtcB by diverse bacterial taxa provides a competitive advantage under stressful conditions.
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Affiliation(s)
- Muhammad Ramzan Manwar
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Changjun Shao
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xing Shi
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Jian Wang
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qiang Lin
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yigang Tong
- Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China
| | - Yu Kang
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Jun Yu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100190, China.
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11
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Duan S, Chen Z, Li Z, Ji R, Gan J, Li J. Purification and enzymatic characterization of the RNA ligase RTCB from Thermus thermophilus. Biotechnol Lett 2019; 41:1051-1057. [PMID: 31280403 DOI: 10.1007/s10529-019-02707-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/04/2019] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To identify the key residues of Thermus thermophilus (T. thermophilus) RTCB in RNA ligation and DNA activation. RESULTS The biochemical activities of RTCB from T. thermophilus were purified, characterized, and compared. Structure and sequence alignment between T. thermophilus RTCB and Pyrococcus horikoshii (P. horikoshii) RTCB identified six conserved residues (D64, D95, N203, H204, E207, H399) that were essential for RNA ligation. Mutation analysis showed that the expression levels of mutants D95A, N203A, H204A, E207A and H399A were relatively low. Compared to wide-type RTCB, variant D64A protein had no RNA ligation and DNA activation activity. In addition, T. thermophilus RTCB showed acceptable catalytic activity of 3'-phosphate DNA activation at 37 °C. CONCLUSION D64 was proved to be essential for RTCB-catalyzed RNA ligation and DNA activation (from 37 to 70 °C) in T. thermophilus.
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Affiliation(s)
- Shuyan Duan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China
| | - Zijun Chen
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China
| | - Zhengyang Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China
| | - Rui Ji
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China
| | - Jianhua Gan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China
| | - Jixi Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Collaborative Innovation Center of Genetics and Development, Fudan University, 200438, Shanghai, China.
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12
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Temmel H, Müller C, Sauert M, Vesper O, Reiss A, Popow J, Martinez J, Moll I. The RNA ligase RtcB reverses MazF-induced ribosome heterogeneity in Escherichia coli. Nucleic Acids Res 2017; 45:4708-4721. [PMID: 27789694 PMCID: PMC5416887 DOI: 10.1093/nar/gkw1018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 10/18/2016] [Indexed: 12/22/2022] Open
Abstract
When Escherichia coli encounters stress, the endoribonuclease MazF initiates a post-transcriptional response that results in the reprogramming of protein synthesis. By removing the 3΄-terminus of the 16S rRNA, MazF generates specialized ribosomes that selectively translate mRNAs likewise processed by MazF. Given the energy required for de novo ribosome biosynthesis, we considered the existence of a repair mechanism operating upon stress relief to recycle the modified ribosomes. Here, we show that the stress-ribosomes and the 3΄-terminal 16S rRNA fragment are stable during adverse conditions. Moreover, employing in vitro and in vivo approaches we demonstrate that the RNA ligase RtcB catalyzes the re-ligation of the truncated 16S rRNA present in specialized ribosomes Thereby their ability to translate canonical mRNAs is fully restored. Together, our findings not only provide a physiological function for the RNA ligase RtcB in bacteria but highlight the reversibility of ribosome heterogeneity, a crucial but hitherto undescribed concept for translational regulation.
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Affiliation(s)
- Hannes Temmel
- Max F. Perutz Laboratories, Center for Molecular Biology, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Christian Müller
- Max F. Perutz Laboratories, Center for Molecular Biology, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Martina Sauert
- Max F. Perutz Laboratories, Center for Molecular Biology, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Oliver Vesper
- Max F. Perutz Laboratories, Center for Molecular Biology, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Ariela Reiss
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), A-1030 Vienna, Austria and Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Johannes Popow
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), A-1030 Vienna, Austria and Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Javier Martinez
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna Biocenter (VBC), A-1030 Vienna, Austria and Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Isabella Moll
- Max F. Perutz Laboratories, Center for Molecular Biology, Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna Biocenter (VBC), Dr Bohr-Gasse 9/4, A-1030 Vienna, Austria
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