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František Potužník J, Nešuta O, Škríba A, Voleníková B, Mititelu MB, Mancini F, Serianni V, Fernandez H, Spustová K, Trylčová J, Vopalensky P, Cahová H. Diadenosine Tetraphosphate (Ap 4 A) Serves as a 5' RNA Cap in Mammalian Cells. Angew Chem Int Ed Engl 2024; 63:e202314951. [PMID: 37934413 DOI: 10.1002/anie.202314951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/02/2023] [Accepted: 11/07/2023] [Indexed: 11/08/2023]
Abstract
The recent expansion of the field of RNA chemical modifications has changed our understanding of post-transcriptional gene regulation. Apart from internal nucleobase modifications, 7-methylguanosine was long thought to be the only eukaryotic RNA cap. However, the discovery of non-canonical RNA caps in eukaryotes revealed a new niche of previously undetected RNA chemical modifications. We are the first to report the existence of a new non-canonical RNA cap, diadenosine tetraphosphate (Ap4 A), in human and rat cell lines. Ap4 A is the most abundant dinucleoside polyphosphate in eukaryotic cells and can be incorporated into RNA by RNA polymerases as a non-canonical initiating nucleotide (NCIN). Using liquid chromatography-mass spectrometry (LC-MS), we show that the amount of capped Ap4 A-RNA is independent of the cellular concentration of Ap4 A. A decapping enzyme screen identifies two enzymes cleaving Ap4 A-RNA,NUDT2 and DXO, both of which also cleave other substrate RNAs in vitro. We further assess the translatability and immunogenicity of Ap4 A-RNA and show that although it is not translated, Ap4 A-RNA is recognized as self by the cell and does not elicit an immune response, making it a natural component of the transcriptome. Our findings open a previously unexplored area of eukaryotic RNA regulation.
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Affiliation(s)
- Jiří František Potužník
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, Prague, 2, Czechia
| | - Ondřej Nešuta
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Anton Škríba
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Barbora Voleníková
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Maria-Bianca Mititelu
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, Prague, 2, Czechia
| | - Flaminia Mancini
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, Prague, 2, Czechia
| | - Valentina Serianni
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
- Department of Cell Biology, Faculty of Science, Charles University, Viničná 7, Prague, 2, Czechia
| | - Henri Fernandez
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Kristína Spustová
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Jana Trylčová
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Pavel Vopalensky
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
| | - Hana Cahová
- Chemical Biology of Nucleic, Acids, Institute of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí 2, Prague, 6, Czechia
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2
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Ben Toumia I, Bachetti T, Chekir-Ghedira L, Profumo A, Ponassi M, Di Domizio A, Izzotti A, Sciacca S, Puglisi C, Forte S, Giuffrida R, Colarossi C, Milardi D, Grasso G, Lanza V, Fiordoro S, Drago G, Tkachenko K, Cardinali B, Romano P, Iervasi E, Vargas GC, Barboro P, Kohnke FH, Rosano C. Fraisinib: a calixpyrrole derivative reducing A549 cell-derived NSCLC tumor in vivo acts as a ligand of the glycine-tRNA synthase, a new molecular target in oncology. Front Pharmacol 2024; 14:1258108. [PMID: 38235113 PMCID: PMC10791888 DOI: 10.3389/fphar.2023.1258108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 11/17/2023] [Indexed: 01/19/2024] Open
Abstract
Background and purpose: Lung cancer is the leading cause of death in both men and women, constituting a major public health problem worldwide. Non-small-cell lung cancer accounts for 85%-90% of all lung cancers. We propose a compound that successfully fights tumor growth in vivo by targeting the enzyme GARS1. Experimental approach: We present an in-depth investigation of the mechanism through which Fraisinib [meso-(p-acetamidophenyl)-calix(4)pyrrole] affects the human lung adenocarcinoma A549 cell line. In a xenografted model of non-small-cell lung cancer, Fraisinib was found to reduce tumor mass volume without affecting the vital parameters or body weight of mice. Through a computational approach, we uncovered that glycyl-tRNA synthetase is its molecular target. Differential proteomics analysis further confirmed that pathways regulated by Fraisinib are consistent with glycyl-tRNA synthetase inhibition. Key results: Fraisinib displays a strong anti-tumoral potential coupled with limited toxicity in mice. Glycyl-tRNA synthetase has been identified and validated as a protein target of this compound. By inhibiting GARS1, Fraisinib modulates different key biological processes involved in tumoral growth, aggressiveness, and invasiveness. Conclusion and implications: The overall results indicate that Fraisinib is a powerful inhibitor of non-small-cell lung cancer growth by exerting its action on the enzyme GARS1 while displaying marginal toxicity in animal models. Together with the proven ability of this compound to cross the blood-brain barrier, we can assess that Fraisinib can kill two birds with one stone: targeting the primary tumor and its metastases "in one shot." Taken together, we suggest that inhibiting GARS1 expression and/or GARS1 enzymatic activity may be innovative molecular targets for cancer treatment.
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Affiliation(s)
| | | | - Leila Chekir-Ghedira
- Unit of Bioactive Natural Substances and Biotechnology, Faculty of Dental Medicine of Monastir, University of Monastir, Monastir, Tunisia
| | - Aldo Profumo
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Marco Ponassi
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | | | - Alberto Izzotti
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
- Department of Experimental Medicine, University of Genova, Genova, Italy
| | | | | | - Stefano Forte
- Istituto Oncologico del Mediterraneo, Viagrande, Italy
| | | | | | - Danilo Milardi
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Giuseppe Grasso
- Department of Chemical Sciences, University of Catania, Catania, Italy
| | - Valeria Lanza
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Stefano Fiordoro
- Department of Experimental Medicine, University of Genova, Genova, Italy
| | - Giacomo Drago
- Department of Experimental Medicine, University of Genova, Genova, Italy
| | | | | | - Paolo Romano
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Erika Iervasi
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | | | - Paola Barboro
- IRCCS Ospedale Policlinico San Martino, Genova, Italy
| | - Franz Heinrich Kohnke
- Dipartimento di Scienze Chimiche, Farmaceutiche ed Ambientali (CHIBIOFARAM), University of Messina, Messina, Italy
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3
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Gupta S, Jani J, Vijayasurya, Mochi J, Tabasum S, Sabarwal A, Pappachan A. Aminoacyl-tRNA synthetase - a molecular multitasker. FASEB J 2023; 37:e23219. [PMID: 37776328 DOI: 10.1096/fj.202202024rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 08/31/2023] [Accepted: 09/12/2023] [Indexed: 10/02/2023]
Abstract
Aminoacyl-tRNA synthetases (AaRSs) are valuable "housekeeping" enzymes that ensure the accurate transmission of genetic information in living cells, where they aminoacylated tRNA molecules with their cognate amino acid and provide substrates for protein biosynthesis. In addition to their translational or canonical function, they contribute to nontranslational/moonlighting functions, which are mediated by the presence of other domains on the proteins. This was supported by several reports which claim that AaRS has a significant role in gene transcription, apoptosis, translation, and RNA splicing regulation. Noncanonical/ nontranslational functions of AaRSs also include their roles in regulating angiogenesis, inflammation, cancer, and other major physio-pathological processes. Multiple AaRSs are also associated with a broad range of physiological and pathological processes; a few even serve as cytokines. Therefore, the multifunctional nature of AaRSs suggests their potential as viable therapeutic targets as well. Here, our discussion will encompass a range of noncanonical functions attributed to Aminoacyl-tRNA Synthetases (AaRSs), highlighting their links with a diverse array of human diseases.
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Affiliation(s)
- Swadha Gupta
- School of Life Sciences, Central University of Gujarat, Gandhinagar, India
| | - Jaykumar Jani
- School of Life Sciences, Central University of Gujarat, Gandhinagar, India
| | - Vijayasurya
- School of Life Sciences, Central University of Gujarat, Gandhinagar, India
| | - Jigneshkumar Mochi
- School of Life Sciences, Central University of Gujarat, Gandhinagar, India
| | - Saba Tabasum
- Dana Farber Cancer Institute, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Akash Sabarwal
- Harvard Medical School, Boston, Massachusetts, USA
- Boston Children's Hospital, Boston, Massachusetts, USA
| | - Anju Pappachan
- School of Life Sciences, Central University of Gujarat, Gandhinagar, India
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4
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Albrecht CJ, Stumpf FM, Krüger L, Niedermeier ML, Stengel F, Marx A. Chemical proteomics reveals interactors of the alarmone diadenosine triphosphate in the cancer cell line H1299. J Pept Sci 2023; 29:e3458. [PMID: 36264037 DOI: 10.1002/psc.3458] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 10/16/2022] [Indexed: 11/11/2022]
Abstract
Intracellular dinucleoside polyphosphates (Npn Ns) have been known for decades but the functional role remains enigmatic. Diadenosine triphosphate (Ap3 A) is one of the most prominent examples, and its intercellular concentration was shown to increase upon cellular stress. By employment of previously reported Ap3 A-based photoaffinity-labeling probes (PALPs) in chemical proteomics, we investigated the Ap3 A interactome in the human lung carcinoma cell line H1299. The cell line is deficient of the fragile histidine triade (Fhit) protein, a hydrolase of Ap3 A and tumor suppressor. Overall, the number of identified potential interaction partners was significantly lower than in the previously investigated HEK293T cell line. Gene ontology term analysis revealed that the identified proteins participate in similar pathways as for HEK293T, but the percentage of proteins involved in RNA-related processes is higher for H1299. The obtained results highlight similarities and differences of the Ap3 A interaction network in different cell lines and give further indications regarding the importance of the presence of Fhit.
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Affiliation(s)
- Christoph J Albrecht
- Department of Chemistry, University of Konstanz, Konstanz, Germany.,Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Florian M Stumpf
- Department of Chemistry, University of Konstanz, Konstanz, Germany.,Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Lena Krüger
- Department of Chemistry, University of Konstanz, Konstanz, Germany.,Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Marie L Niedermeier
- Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Florian Stengel
- Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany.,Department of Biology, University of Konstanz, Konstanz, Germany
| | - Andreas Marx
- Department of Chemistry, University of Konstanz, Konstanz, Germany.,Konstanz Research School-Chemical Biology, University of Konstanz, Konstanz, Germany
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5
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Andreev DE, Niepmann M, Shatsky IN. Elusive Trans-Acting Factors Which Operate with Type I (Poliovirus-like) IRES Elements. Int J Mol Sci 2022; 23:ijms232415497. [PMID: 36555135 PMCID: PMC9778869 DOI: 10.3390/ijms232415497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
The phenomenon of internal initiation of translation was discovered in 1988 on poliovirus mRNA. The prototypic cis-acting element in the 5' untranslated region (5'UTR) of poliovirus mRNA, which is able to direct initiation at an internal start codon without the involvement of a cap structure, has been called an IRES (Internal Ribosome Entry Site or Segment). Despite its early discovery, poliovirus and other related IRES elements of type I are poorly characterized, and it is not yet clear which host proteins (a.k.a. IRES trans-acting factors, ITAFs) are required for their full activity in vivo. Here we discuss recent and old results devoted to type I IRESes and provide evidence that Poly(rC) binding protein 2 (PCBP2), Glycyl-tRNA synthetase (GARS), and Cold Shock Domain Containing E1 (CSDE1, also known as UNR) are major regulators of type I IRES activity.
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Affiliation(s)
- Dmitry E. Andreev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, 117997 Moscow, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Michael Niepmann
- Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, 35392 Giessen, Germany
| | - Ivan N. Shatsky
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
- Correspondence:
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6
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Ferguson F, McLennan AG, Urbaniak MD, Jones NJ, Copeland NA. Re-evaluation of Diadenosine Tetraphosphate (Ap 4A) From a Stress Metabolite to Bona Fide Secondary Messenger. Front Mol Biosci 2020; 7:606807. [PMID: 33282915 PMCID: PMC7705103 DOI: 10.3389/fmolb.2020.606807] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/19/2020] [Indexed: 01/14/2023] Open
Abstract
Cellular homeostasis requires adaption to environmental stress. In response to various environmental and genotoxic stresses, all cells produce dinucleoside polyphosphates (NpnNs), the best studied of which is diadenosine tetraphosphate (Ap4A). Despite intensive investigation, the precise biological roles of these molecules have remained elusive. However, recent studies have elucidated distinct and specific signaling mechanisms for these nucleotides in prokaryotes and eukaryotes. This review summarizes these key discoveries and describes the mechanisms of Ap4A and Ap4N synthesis, the mediators of the cellular responses to increased intracellular levels of these molecules and the hydrolytic mechanisms required to maintain low levels in the absence of stress. The intracellular responses to dinucleotide accumulation are evaluated in the context of the "friend" and "foe" scenarios. The "friend (or alarmone) hypothesis" suggests that ApnN act as bona fide secondary messengers mediating responses to stress. In contrast, the "foe" hypothesis proposes that ApnN and other NpnN are produced by non-canonical enzymatic synthesis as a result of physiological and environmental stress in critically damaged cells but do not actively regulate mitigating signaling pathways. In addition, we will discuss potential target proteins, and critically assess new evidence supporting roles for ApnN in the regulation of gene expression, immune responses, DNA replication and DNA repair. The recent advances in the field have generated great interest as they have for the first time revealed some of the molecular mechanisms that mediate cellular responses to ApnN. Finally, areas for future research are discussed with possible but unproven roles for intracellular ApnN to encourage further research into the signaling networks that are regulated by these nucleotides.
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Affiliation(s)
- Freya Ferguson
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom.,Materials Science Institute, Lancaster University, Lancaster, United Kingdom
| | - Alexander G McLennan
- Department of Molecular Physiology and Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Michael D Urbaniak
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom
| | - Nigel J Jones
- Department of Molecular Physiology and Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Nikki A Copeland
- Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, United Kingdom.,Materials Science Institute, Lancaster University, Lancaster, United Kingdom
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7
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Bazany-Rodríguez IJ, Salomón-Flores MK, Bautista-Renedo JM, González-Rivas N, Dorazco-González A. Chemosensing of Guanosine Triphosphate Based on a Fluorescent Dinuclear Zn(II)-Dipicolylamine Complex in Water. Inorg Chem 2020; 59:7739-7751. [PMID: 32391691 DOI: 10.1021/acs.inorgchem.0c00777] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Guanosine triphosphate (GTP) is a key biomarker of multiple cellular processes and human diseases. The new fluorescent dinuclear complex [Zn2(L)(S)][OTf]4, 1 (asymmetric ligand, L = 5,8-Bis{[bis(2-pyridylmethyl)amino] methyl}quinoline, S = solvent, and OTf = triflate anion) was synthesized and studied in-depth as a chemosensor for nucleoside polyphosphates and inorganic anions in pure water. Additions at neutral pH of nucleoside triphosphates, guanosine diphosphate, guanosine monophosphate, and pyrophosphate (PPi) to 1 quench its blue emission (λem = 410 nm) with a pronounced selectivity toward GTP over other anions, including adenosine triphosphate (ATP), uridine triphosphate (UTP), and cytidine triphosphate (CTP). The efficient quenching response by the addition of GTP was observed in the presence of coexisting species in blood plasma and urine with a detection limit of 9.2 μmol L-1. GTP also shows much tighter binding to the receptor 1 on a submicromolar level. On the basis of multiple spectroscopic tools (1H, 31P NMR, UV-vis, and fluorescence) and DFT calculations, the binding mode is proposed through three-point recognition involving the simultaneous coordination of the N7 atom of the guanosine motif and two phosphate groups to the two Zn(II) atoms. Spectroscopic studies, MS-ESI, and DFT suggested that GTP bound to 1 in 1:1 and 2:2 models with high overall binding constants of log β1 (1:1) = 6.05 ± 0.01 and log β2 = 10.91 ± 0.03, respectively. The optical change and selectivity are attributed to the efficient binding of GTP to 1 by the combination of a strong electrostatic contribution and synergic effects of coordination bonds. Such GTP selectivity of an asymmetric metal-based receptor in water is still rare.
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Affiliation(s)
- Iván J Bazany-Rodríguez
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria México, 04510, Distrito Federal de México, México
| | - María K Salomón-Flores
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria México, 04510, Distrito Federal de México, México
| | - Joanatan M Bautista-Renedo
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM, km 14.5 Carrera Toluca-Atlacomulco, Campus UAEMex "El Rosedal" San Cayetano-Toluca, 50200 Toluca de Lerdo, Estado de México, México
| | - Nelly González-Rivas
- Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM, km 14.5 Carrera Toluca-Atlacomulco, Campus UAEMex "El Rosedal" San Cayetano-Toluca, 50200 Toluca de Lerdo, Estado de México, México
| | - Alejandro Dorazco-González
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria México, 04510, Distrito Federal de México, México
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8
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Formation of the Alarmones Diadenosine Triphosphate and Tetraphosphate by Ubiquitin- and Ubiquitin-like-Activating Enzymes. Cell Chem Biol 2019; 26:1535-1543.e5. [PMID: 31492597 DOI: 10.1016/j.chembiol.2019.08.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/19/2019] [Accepted: 08/08/2019] [Indexed: 01/14/2023]
Abstract
Diadenosine polyphosphates (ApnAs) such as diadenosine tri- and tetraphosphates are formed in prokaryotic as well as eukaryotic cells. Since upon stress intracellular ApnA concentrations increase, it was postulated that ApnAs are alarmones triggering stress-adaptive processes. The major synthesis pathway of ApnAs is assumed to be a side reaction of amino acid activation. How this process is linked to stress adaptation remains enigmatic. The first step of one of the most prominent eukaryotic post-translational modification systems-the conjugation of ubiquitin (Ub) and ubiquitin-like proteins (Ubl) to target proteins-involves the formation of an adenylate as intermediate. Like ApnA formation, Ub and Ubl conjugation is significantly enhanced during stress conditions. Here, we demonstrate that diadenosine tri- and tetraphosphates are indeed synthesized during activation of Ub and Ubls. This links one of the most prevalent eukaryotic protein-modification systems to ApnA formation for the first time.
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9
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Structure-function studies of the asparaginyl-tRNA synthetase from Fasciola gigantica: understanding the role of catalytic and non-catalytic domains. Biochem J 2018; 475:3377-3391. [DOI: 10.1042/bcj20180700] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 09/29/2018] [Accepted: 10/04/2018] [Indexed: 01/14/2023]
Abstract
The asparaginyl-tRNA synthetase (NRS) catalyzes the attachment of asparagine to its cognate tRNA during translation. NRS first catalyzes the binding of Asn and ATP to form the NRS-asparaginyl adenylate complex, followed by the esterification of Asn to its tRNA. We investigated the role of constituent domains in regulating the structure and activity of Fasciola gigantica NRS (FgNRS). We cloned the full-length FgNRS, along with its various truncated forms, expressed, and purified the corresponding proteins. Size exclusion chromatography indicated a role of the anticodon-binding domain (ABD) of FgNRS in protein dimerization. The N-terminal domain (NTD) was not essential for cognate tRNA binding, and the hinge region between the ABD and the C-terminal domain (CTD) was crucial for regulating the enzymatic activity. Molecular docking and fluorescence quenching experiments elucidated the binding affinities of the substrates to various domains. The molecular dynamics simulation of the modeled protein showed the presence of an unstructured region between the NTD and ABD that exhibited a large number of conformations over time, and further analysis indicated this region to be intrinsically disordered. The present study provides information on the structural and functional regulation, protein-substrate(s) interactions and dynamics, and the role of non-catalytic domains in regulating the activity of FgNRS.
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10
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Eberlein C, Nielly-Thibault L, Maaroufi H, Dubé AK, Leducq JB, Charron G, Landry CR. The Rapid Evolution of an Ohnolog Contributes to the Ecological Specialization of Incipient Yeast Species. Mol Biol Evol 2017; 34:2173-2186. [PMID: 28482005 DOI: 10.1093/molbev/msx153] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Identifying the molecular changes that lead to ecological specialization during speciation is one of the major goals of molecular evolution. One question that remains to be thoroughly investigated is whether ecological specialization derives strictly from adaptive changes and their associated trade-offs, or from conditionally neutral mutations that accumulate under relaxed selection. We used whole-genome sequencing, genome annotation and computational analyses to identify genes that have rapidly diverged between two incipient species of Saccharomyces paradoxus that occupy different climatic regions along a south-west to north-east gradient. As candidate loci for ecological specialization, we identified genes that show signatures of adaptation and accelerated rates of amino acid substitutions, causing asymmetric evolution between lineages. This set of genes includes a glycyl-tRNA-synthetase, GRS2, which is known to be transcriptionally induced under heat stress in the model and sister species S. cerevisiae. Molecular modelling, expression analysis and fitness assays suggest that the accelerated evolution of this gene in the Northern lineage may be caused by relaxed selection. GRS2 arose during the whole-genome duplication (WGD) that occurred 100 million years ago in the yeast lineage. While its ohnolog GRS1 has been preserved in all post-WGD species, GRS2 has frequently been lost and is evolving rapidly, suggesting that the fate of this ohnolog is still to be resolved. Our results suggest that the asymmetric evolution of GRS2 between the two incipient S. paradoxus species contributes to their restricted climatic distributions and thus that ecological specialization derives at least partly from relaxed selection rather than a molecular trade-off resulting from adaptive evolution.
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Affiliation(s)
- Chris Eberlein
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.,PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Québec, QC, Canada
| | - Lou Nielly-Thibault
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.,PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Québec, QC, Canada.,Big Data Research Center (CRDM), Université Laval, Québec, QC, Canada
| | - Halim Maaroufi
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Alexandre K Dubé
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.,PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Québec, QC, Canada
| | - Jean-Baptiste Leducq
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Guillaume Charron
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.,PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Québec, QC, Canada
| | - Christian R Landry
- Département de Biologie, Université Laval, Québec, QC, Canada.,Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada.,PROTEO, The Quebec Network for Research on Protein Function, Engineering and Applications, Québec, QC, Canada.,Big Data Research Center (CRDM), Université Laval, Québec, QC, Canada
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11
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Götz KH, Hacker SM, Mayer D, Dürig JN, Stenger S, Marx A. Inhibitors of the Diadenosine Tetraphosphate Phosphorylase Rv2613c of Mycobacterium tuberculosis. ACS Chem Biol 2017; 12:2682-2689. [PMID: 28892605 DOI: 10.1021/acschembio.7b00653] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intracellular concentration of diadenosine tetraphospate (Ap4A) increases upon exposure to stress conditions. Despite being discovered over 50 years ago, the cellular functions of Ap4A are still enigmatic. If and how the varied Ap4A is a signal and involved in the signaling pathways leading to an appropriate cellular response remain to be discovered. Because the turnover of Ap4A by Ap4A cleaving enzymes is rapid, small molecule inhibitors for these enzymes would provide tools for the more detailed study of the role of Ap4A. Here, we describe the development of a high-throughput screening assay based on a fluorogenic Ap4A substrate for the identification and optimization of small molecule inhibitors for Ap4A cleaving enzymes. As proof-of-concept we screened a library of over 42 000 compounds toward their inhibitory activity against the Ap4A phosphorylase (Rv2613c) of Mycobacterium tuberculosis (Mtb). A sulfanylacrylonitril derivative with an IC50 of 260 ± 50 nM in vitro was identified. Multiple derivatives were synthesized to further optimize their properties with respect to their in vitro IC50 values and their cytotoxicity against human cells (HeLa). In addition, we selected two hits to study their antimycobacterial activity against virulent Mtb to show that they might be candidates for further development of antimycobacterial agents against multidrug-resistant Mtb.
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Affiliation(s)
- Kathrin H. Götz
- Department
of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Stephan M. Hacker
- Department
of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Daniel Mayer
- Institute
for Medical Microbiology and Hygiene, University Hospital of Ulm, Albert-Einstein-Allee
11, D-89081 Ulm, Germany
| | - Jan-Niklas Dürig
- Department
of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Steffen Stenger
- Institute
for Medical Microbiology and Hygiene, University Hospital of Ulm, Albert-Einstein-Allee
11, D-89081 Ulm, Germany
| | - Andreas Marx
- Department
of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
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12
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Despotović D, Brandis A, Savidor A, Levin Y, Fumagalli L, Tawfik DS. Diadenosine tetraphosphate (Ap4A) - an E. coli alarmone or a damage metabolite? FEBS J 2017; 284:2194-2215. [PMID: 28516732 DOI: 10.1111/febs.14113] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 05/15/2017] [Indexed: 12/21/2022]
Abstract
Under stress, metabolism is changing: specific up- or down-regulation of proteins and metabolites occurs as well as side effects. Distinguishing specific stress-signaling metabolites (alarmones) from side products (damage metabolites) is not trivial. One example is diadenosine tetraphosphate (Ap4A) - a side product of aminoacyl-tRNA synthetases found in all domains of life. The earliest observations suggested that Ap4A serves as an alarmone for heat stress in Escherichia coli. However, despite 50 years of research, the signaling mechanisms associated with Ap4A remain unknown. We defined a set of criteria for distinguishing alarmones from damage metabolites to systematically classify Ap4A. In a nutshell, no indications for a signaling cascade that is triggered by Ap4A were found; rather, we found that Ap4A is efficiently removed in a constitutive, nonregulated manner. Several fold perturbations in Ap4A concentrations have no effect, yet accumulation at very high levels is toxic due to disturbance of zinc homeostasis, and also because Ap4A's structural overlap with ATP can result in spurious binding and inactivation of ATP-binding proteins. Overall, Ap4A met all criteria for a damage metabolite. While we do not exclude any role in signaling, our results indicate that the damage metabolite option should be considered as the null hypothesis when examining Ap4A and other metabolites whose levels change upon stress.
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Affiliation(s)
- Dragana Despotović
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Alexander Brandis
- Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Alon Savidor
- Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Yishai Levin
- Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Laura Fumagalli
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, Italy
| | - Dan S Tawfik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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13
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Oka M, Takegawa K, Kimura Y. Lysyl-tRNA synthetase from Myxococcus xanthus catalyzes the formation of diadenosine penta- and hexaphosphates from adenosine tetraphosphate. Arch Biochem Biophys 2016; 604:152-8. [PMID: 27392456 DOI: 10.1016/j.abb.2016.07.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/23/2016] [Accepted: 07/02/2016] [Indexed: 11/18/2022]
Abstract
Myxococcus xanthus lysyl-tRNA synthetase (LysS) produces diadenosine tetraphosphate (Ap4A) from ATP in the presence of Mn(2+); in the present study, it also generated Ap4 from ATP and triphosphate. When ATP and Ap4 were incubated with LysS and pyrophosphatase, first Ap4A, Ap5A, and ADP, and then Ap5, Ap6A, and Ap3A were generated. The results suggest that in the first step, LysS can form lysyl-AMP and lysyl-ADP intermediates from Ap4 and release triphosphate and diphosphate, respectively, whereas in the second step, it can produce Ap5 from lysyl-ADP with triphosphate, and Ap6A from lysyl-ADP with Ap4. In addition, in the presence of Ap4 and pyrophosphatase, but absence of ATP, LysS also generates diadenosine oligophosphates (ApnAs: n = 3-6). These results indicate that LysS has the ability to catalyze the formation of various ApnAs from Ap4 in the presence of pyrophosphatase. Furthermore, the formation of Ap4A by LysS was inhibited by tRNA(Lys) in the presence of 1 mM ATP. To the best of our knowledge, this is the first report of Ap5A and Ap6A synthesis by lysyl-tRNA synthetase.
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Affiliation(s)
- Manami Oka
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa, Japan
| | - Kaoru Takegawa
- Department of Bioscience and Biotechnology, Kyusyu University, Hakozaki, Higashi-ku, Fukuoka, Japan
| | - Yoshio Kimura
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa, Japan.
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14
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Storkebaum E. Peripheral neuropathy via mutant tRNA synthetases: Inhibition of protein translation provides a possible explanation. Bioessays 2016; 38:818-29. [PMID: 27352040 PMCID: PMC5094542 DOI: 10.1002/bies.201600052] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recent evidence indicates that inhibition of protein translation may be a common pathogenic mechanism for peripheral neuropathy associated with mutant tRNA synthetases (aaRSs). aaRSs are enzymes that ligate amino acids to their cognate tRNA, thus catalyzing the first step of translation. Dominant mutations in five distinct aaRSs cause Charcot‐Marie‐Tooth (CMT) peripheral neuropathy, characterized by length‐dependent degeneration of peripheral motor and sensory axons. Surprisingly, loss of aminoacylation activity is not required for mutant aaRSs to cause CMT. Rather, at least for some mutations, a toxic‐gain‐of‐function mechanism underlies CMT‐aaRS. Interestingly, several mutations in two distinct aaRSs were recently shown to inhibit global protein translation in Drosophila models of CMT‐aaRS, by a mechanism independent of aminoacylation, suggesting inhibition of translation as a common pathogenic mechanism. Future research aimed at elucidating the molecular mechanisms underlying the translation defect induced by CMT‐mutant aaRSs should provide novel insight into the molecular pathogenesis of these incurable diseases.
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Affiliation(s)
- Erik Storkebaum
- Molecular Neurogenetics Laboratory, Max Planck Institute for Molecular Biomedicine, Münster, Germany.,Faculty of Medicine, University of Münster, Münster, Germany
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15
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Neddylation requires glycyl-tRNA synthetase to protect activated E2. Nat Struct Mol Biol 2016; 23:730-7. [PMID: 27348078 PMCID: PMC4972647 DOI: 10.1038/nsmb.3250] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/01/2016] [Indexed: 12/31/2022]
Abstract
Neddylation is a post-translational modification that controls cell cycle and proliferation by conjugating the ubiquitin-like protein NEDD8 to specific targets. Here we report that glycyl-tRNA synthetase (GlyRS), an essential enzyme for protein synthesis, also plays a critical role in neddylation. In human cells, knockdown of GlyRS, but not a different tRNA synthetase, decreases the global level of neddylation and causes cell cycle abnormality. This function of GlyRS is achieved through direct interactions with multiple components of the neddylation pathway, including NEDD8, E1, and E2 (Ubc12). Using various structural and functional approaches, we show that GlyRS binds to the APPBP1 subunit of E1 to capture and protect the activated E2 (NEDD8-conjugated Ubc12) before it reaches a downstream target. Therefore, GlyRS functions as a chaperone to critically support neddylation. This function is likely to be conserved in all eukaryotic GlyRS, and may contribute to the strong association of GlyRS with cancer progression.
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16
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Deng X, Qin X, Chen L, Jia Q, Zhang Y, Zhang Z, Lei D, Ren G, Zhou Z, Wang Z, Li Q, Xie W. Large Conformational Changes of Insertion 3 in Human Glycyl-tRNA Synthetase (hGlyRS) during Catalysis. J Biol Chem 2016; 291:5740-5752. [PMID: 26797133 PMCID: PMC4786711 DOI: 10.1074/jbc.m115.679126] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 01/04/2016] [Indexed: 12/14/2022] Open
Abstract
Glycyl-tRNA synthetase (GlyRS) is the enzyme that covalently links glycine to cognate tRNA for translation. It is of great research interest because of its nonconserved quaternary structures, unique species-specific aminoacylation properties, and noncanonical functions in neurological diseases, but none of these is fully understood. We report two crystal structures of human GlyRS variants, in the free form and in complex with tRNA(Gly) respectively, and reveal new aspects of the glycylation mechanism. We discover that insertion 3 differs considerably in conformation in catalysis and that it acts like a "switch" and fully opens to allow tRNA to bind in a cross-subunit fashion. The flexibility of the protein is supported by molecular dynamics simulation, as well as enzymatic activity assays. The biophysical and biochemical studies suggest that human GlyRS may utilize its flexibility for both the traditional function (regulate tRNA binding) and alternative functions (roles in diseases).
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Affiliation(s)
- Xiangyu Deng
- From the State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,; the Center for Cellular and Structural Biology and
| | - Xiangjing Qin
- the South China Sea Institute, Chinese Academy of Sciences, Guangzhou, Guangdong 510301, China
| | - Lei Chen
- From the State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,; the Center for Cellular and Structural Biology and
| | - Qian Jia
- From the State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,; the Center for Cellular and Structural Biology and
| | - Yonghui Zhang
- the Hefei National Laboratory for Physical Science at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China, and
| | - Zhiyong Zhang
- the Hefei National Laboratory for Physical Science at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230026, China, and
| | - Dongsheng Lei
- the Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Gang Ren
- the Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Zhihong Zhou
- From the State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,; the Center for Cellular and Structural Biology and
| | - Zhong Wang
- the Center for Cellular and Structural Biology and; the School of Pharmaceutical Sciences, Sun Yat-Sen University, University City, Guangzhou, Guangdong 510006, China
| | - Qing Li
- the Center for Cellular and Structural Biology and; the School of Pharmaceutical Sciences, Sun Yat-Sen University, University City, Guangzhou, Guangdong 510006, China
| | - Wei Xie
- From the State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China,; the Center for Cellular and Structural Biology and.
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17
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Fang P, Guo M. Evolutionary Limitation and Opportunities for Developing tRNA Synthetase Inhibitors with 5-Binding-Mode Classification. Life (Basel) 2015; 5:1703-25. [PMID: 26670257 PMCID: PMC4695845 DOI: 10.3390/life5041703] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 12/30/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are enzymes that catalyze the transfer of amino acids to their cognate tRNAs as building blocks for translation. Each of the aaRS families plays a pivotal role in protein biosynthesis and is indispensable for cell growth and survival. In addition, aaRSs in higher species have evolved important non-translational functions. These translational and non-translational functions of aaRS are attractive for developing antibacterial, antifungal, and antiparasitic agents and for treating other human diseases. The interplay between amino acids, tRNA, ATP, EF-Tu and non-canonical binding partners, had shaped each family with distinct pattern of key sites for regulation, with characters varying among species across the path of evolution. These sporadic variations in the aaRSs offer great opportunity to target these essential enzymes for therapy. Up to this day, growing numbers of aaRS inhibitors have been discovered and developed. Here, we summarize the latest developments and structural studies of aaRS inhibitors, and classify them with distinct binding modes into five categories.
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Affiliation(s)
- Pengfei Fang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
- Department of Cancer Biology, The Scripps Research Institute, Scripps Florida, 130 Scripps Way, Jupiter, FL 33458, USA.
| | - Min Guo
- Department of Cancer Biology, The Scripps Research Institute, Scripps Florida, 130 Scripps Way, Jupiter, FL 33458, USA.
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18
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Marriott AS, Copeland NA, Cunningham R, Wilkinson MC, McLennan AG, Jones NJ. Diadenosine 5', 5'''-P(1),P(4)-tetraphosphate (Ap4A) is synthesized in response to DNA damage and inhibits the initiation of DNA replication. DNA Repair (Amst) 2015. [PMID: 26204256 DOI: 10.1016/j.dnarep.2015.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The level of intracellular diadenosine 5', 5'''-P(1),P(4)-tetraphosphate (Ap4A) increases several fold in mammalian cells treated with non-cytotoxic doses of interstrand DNA-crosslinking agents such as mitomycin C. It is also increased in cells lacking DNA repair proteins including XRCC1, PARP1, APTX and FANCG, while >50-fold increases (up to around 25 μM) are achieved in repair mutants exposed to mitomycin C. Part of this induced Ap4A is converted into novel derivatives, identified as mono- and di-ADP-ribosylated Ap4A. Gene knockout experiments suggest that DNA ligase III is primarily responsible for the synthesis of damage-induced Ap4A and that PARP1 and PARP2 can both catalyze its ADP-ribosylation. Degradative proteins such as aprataxin may also contribute to the increase. Using a cell-free replication system, Ap4A was found to cause a marked inhibition of the initiation of DNA replicons, while elongation was unaffected. Maximum inhibition of 70-80% was achieved with 20 μM Ap4A. Ap3A, Ap5A, Gp4G and ADP-ribosylated Ap4A were without effect. It is proposed that Ap4A acts as an important inducible ligand in the DNA damage response to prevent the replication of damaged DNA.
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Affiliation(s)
- Andrew S Marriott
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Nikki A Copeland
- Division of Biomedical and Life Sciences, University of Lancaster, Lancaster LA1 4YG, UK
| | - Ryan Cunningham
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Mark C Wilkinson
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Alexander G McLennan
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK.
| | - Nigel J Jones
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
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19
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Enzymatic characterization of a class II lysyl-tRNA synthetase, LysS, from Myxococcus xanthus. Arch Biochem Biophys 2015; 579:33-9. [PMID: 26048731 DOI: 10.1016/j.abb.2015.05.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 11/21/2022]
Abstract
Lysyl-tRNA synthetases efficiently produce diadenosine tetraphosphate (Ap4A) from lysyl-AMP with ATP in the absence of tRNA. We characterized recombinant class II lysyl-tRNA synthetase (LysS) from Myxococcus xanthus and found that it is monomeric and requires Mn(2+) for the synthesis of Ap4A. Surprisingly, Zn(2+) inhibited enzyme activity in the presence of Mn(2+). When incubated with ATP, Mn(2+), lysine, and inorganic pyrophosphatase, LysS first produced Ap4A and ADP, then converted Ap4A to diadenosine triphosphate (Ap3A), and finally converted Ap3A to ADP, the end product of the reaction. Recombinant LysS retained Ap4A synthase activity without lysine addition. Additionally, when incubated with Ap4A (minus pyrophosphatase), LysS converted Ap4A mainly ATP and AMP, or ADP in the presence or absence of lysine, respectively. These results demonstrate that M. xanthus LysS has different enzymatic properties from class II lysyl-tRNA synthetases previously reported.
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20
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Kaur G, Subramanian S. The insertion domain 1 of class IIA dimeric glycyl-tRNA synthetase is a rubredoxin-like zinc ribbon. J Struct Biol 2015; 190:38-46. [PMID: 25721219 DOI: 10.1016/j.jsb.2015.02.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 02/11/2015] [Accepted: 02/12/2015] [Indexed: 01/20/2023]
Abstract
The insertion domain 1 (ID1) of class IIA dimeric glycyl-tRNA synthetase (α2GRS) is an appended domain in the core catalytic region of the enzyme. ID1 has been shown to play a role in tRNA aminoacylation, mediating interaction with the acceptor arm of tRNA and diadenosine tetraphosphate (Ap4A) synthesis. Mutations in α2GRS, including those in the ID1 region, have been implicated in distal hereditary motor neuropathy-V (dHMN-V) and Charcot-Marie-Tooth (CMT) disease. Through sequence and structure based evolutionary analysis, we show that ID1 of α2GRS is a rubredoxin-like zinc ribbon domain. The zinc-chelating cysteines of ID1 are well conserved in all archaeal versions of the enzyme and also in several eukaryotes, which most likely have acquired them via horizontal gene transfer from bacteria; but in all other eukaryotes, the zinc-chelating residues are not preserved. ID1 from bacteria display a selective preservation of zinc-binding residues, ranging from complete conservation to complete loss. The ID1 from different organisms harbor variable-sized non-conserved insertions between the two zinc-binding half-sites of the zinc ribbon. Three of the previously identified CMT-associated mutations in α2GRS, viz., human D146N, mouse C157R and human S211F, are located in the zinc ribbon region of ID1. Interestingly, human Asp146 which is implicated in the synthesis of Ap4A, a molecule known to act during neuronal transmission, has also been reported to be mutated in dHMN-V, suggesting a possible link between hereditary motor neuropathy and Ap4A synthesis.
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Affiliation(s)
- Gurmeet Kaur
- CSIR-Institute of Microbial Technology, Sector 39A, Chandigarh, India
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21
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Qin X, Hao Z, Tian Q, Zhang Z, Zhou C, Xie W. Cocrystal structures of glycyl-tRNA synthetase in complex with tRNA suggest multiple conformational states in glycylation. J Biol Chem 2014; 289:20359-69. [PMID: 24898252 PMCID: PMC4106348 DOI: 10.1074/jbc.m114.557249] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 05/31/2014] [Indexed: 12/16/2022] Open
Abstract
Aminoacyl-tRNA synthetases are an ancient enzyme family that specifically charges tRNA molecules with cognate amino acids for protein synthesis. Glycyl-tRNA synthetase (GlyRS) is one of the most intriguing aminoacyl-tRNA synthetases due to its divergent quaternary structure and abnormal charging properties. In the past decade, mutations of human GlyRS (hGlyRS) were also found to be associated with Charcot-Marie-Tooth disease. However, the mechanisms of traditional and alternative functions of hGlyRS are poorly understood due to a lack of studies at the molecular basis. In this study we report crystal structures of wild type and mutant hGlyRS in complex with tRNA and with small substrates and describe the molecular details of enzymatic recognition of the key tRNA identity elements in the acceptor stem and the anticodon loop. The cocrystal structures suggest that insertions 1 and 3 work together with the active site in a cooperative manner to facilitate efficient substrate binding. Both the enzyme and tRNA molecules undergo significant conformational changes during glycylation. A working model of multiple conformations for hGlyRS catalysis is proposed based on the crystallographic and biochemical studies. This study provides insights into the catalytic pathway of hGlyRS and may also contribute to our understanding of Charcot-Marie-Tooth disease.
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Affiliation(s)
- Xiangjing Qin
- From the Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, School of Life Sciences, The Sun Yat-Sen University, Guangzhou 510275, China, Center for Cellular and Structural Biology, The Sun Yat-Sen University, 132 E. Circle, University City, Guangzhou 510006, China, and
| | - Zhitai Hao
- From the Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, School of Life Sciences, The Sun Yat-Sen University, Guangzhou 510275, China, Center for Cellular and Structural Biology, The Sun Yat-Sen University, 132 E. Circle, University City, Guangzhou 510006, China, and
| | - Qingnan Tian
- From the Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, School of Life Sciences, The Sun Yat-Sen University, Guangzhou 510275, China, Center for Cellular and Structural Biology, The Sun Yat-Sen University, 132 E. Circle, University City, Guangzhou 510006, China, and
| | - Zhemin Zhang
- From the Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, School of Life Sciences, The Sun Yat-Sen University, Guangzhou 510275, China, Center for Cellular and Structural Biology, The Sun Yat-Sen University, 132 E. Circle, University City, Guangzhou 510006, China, and
| | - Chun Zhou
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065
| | - Wei Xie
- From the Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, School of Life Sciences, The Sun Yat-Sen University, Guangzhou 510275, China, Center for Cellular and Structural Biology, The Sun Yat-Sen University, 132 E. Circle, University City, Guangzhou 510006, China, and
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22
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Yang XL. Structural disorder in expanding the functionome of aminoacyl-tRNA synthetases. ACTA ACUST UNITED AC 2014; 20:1093-9. [PMID: 24054183 DOI: 10.1016/j.chembiol.2013.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 11/28/2022]
Abstract
Over the past decade, aminoacyl-tRNA synthetases (AARSs) have emerged as a new class of regulatory proteins with widespread functions beyond their classic role in protein synthesis. The functional expansion concurs with the incorporation of new domains and motifs to AARSs and coincides with the emergence of the multi-synthetase complex (MSC) during the course of eukaryotic evolution. Notably, the new domains in AARSs are often found to be structurally disordered or to be linked to the enzyme cores via unstructured linkers. We performed bioinformatic analysis and classified the 20 human cytoplasmic AARSs into three groups based on their propensities for structural disorder. The analysis also suggests that, while the assembly of the MSC mainly involves ordered structural domains, structurally disordered regions play an important role in activating and expanding the regulatory functions of AARSs.
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Affiliation(s)
- Xiang-Lei Yang
- Departments of Chemical Physiology and Cell and Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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23
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Dorazco-González A, Alamo MF, Godoy-Alcántar C, Höpfl H, Yatsimirsky AK. Fluorescent anion sensing by bisquinolinium pyridine-2,6-dicarboxamide receptors in water. RSC Adv 2014. [DOI: 10.1039/c3ra44363a] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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24
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Amino-acyl tRNA synthetases generate dinucleotide polyphosphates as second messengers: functional implications. Top Curr Chem (Cham) 2013; 344:189-206. [PMID: 23536246 DOI: 10.1007/128_2013_426] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In this chapter we describe aminoacyl-tRNA synthetase (aaRS) production of dinucleotide polyphosphate in response to stimuli, their interaction with various signaling pathways, and the role of diadenosine tetraphosphate and diadenosine triphosphate as second messengers. The primary role of aaRS is to mediate aminoacylation of cognate tRNAs, thereby providing a central role for the decoding of genetic code during protein translation. However, recent studies suggest that during evolution, "moonlighting" or non-canonical roles were acquired through incorporation of additional domains, leading to regulation by aaRSs of a spectrum of important biological processes, including cell cycle control, tissue differentiation, cellular chemotaxis, and inflammation. In addition to aminoacylation of tRNA, most aaRSs can also produce dinucleotide polyphosphates in a variety of physiological conditions. The dinucleotide polyphosphates produced by aaRS are biologically active both extra- and intra-cellularly, and seem to function as important signaling molecules. Recent findings established the role of dinucleotide polyphosphates as second messengers.
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Perona JJ, Hadd A. Structural diversity and protein engineering of the aminoacyl-tRNA synthetases. Biochemistry 2012; 51:8705-29. [PMID: 23075299 DOI: 10.1021/bi301180x] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRS) are the enzymes that ensure faithful transmission of genetic information in all living cells, and are central to the developing technologies for expanding the capacity of the translation apparatus to incorporate nonstandard amino acids into proteins in vivo. The 24 known aaRS families are divided into two classes that exhibit functional evolutionary convergence. Each class features an active site domain with a common fold that binds ATP, the amino acid, and the 3'-terminus of tRNA, embellished by idiosyncratic further domains that bind distal portions of the tRNA and enhance specificity. Fidelity in the expression of the genetic code requires that the aaRS be selective for both amino acids and tRNAs, a substantial challenge given the presence of structurally very similar noncognate substrates of both types. Here we comprehensively review central themes concerning the architectures of the protein structures and the remarkable dual-substrate selectivities, with a view toward discerning the most important issues that still substantially limit our capacity for rational protein engineering. A suggested general approach to rational design is presented, which should yield insight into the identities of the protein-RNA motifs at the heart of the genetic code, while also offering a basis for improving the catalytic properties of engineered tRNA synthetases emerging from genetic selections.
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Affiliation(s)
- John J Perona
- Department of Chemistry, Portland State University, Portland, Oregon 97207, United States.
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Tan K, Zhou M, Zhang R, Anderson WF, Joachimiak A. The crystal structures of the α-subunit of the α(2)β (2) tetrameric Glycyl-tRNA synthetase. ACTA ACUST UNITED AC 2012; 13:233-9. [PMID: 23054484 DOI: 10.1007/s10969-012-9142-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Accepted: 09/11/2012] [Indexed: 11/25/2022]
Abstract
Aminoacyl-tRNA synthetases (AARSs) are ligases (EC.6.1.1.-) that catalyze the acylation of amino acids to their cognate tRNAs in the process of translating genetic information from mRNA to protein. Their amino acid and tRNA specificity are crucial for correctly translating the genetic code. Glycine is the smallest amino acid and the glycyl-tRNA synthetase (GlyRS) belongs to Class II AARSs. The enzyme is unusual because it can assume different quaternary structures. In eukaryotes, archaebacteria and some bacteria, it forms an α(2) homodimer. In some bacteria, GlyRS is an α(2)β(2) heterotetramer and shows a distant similarity to α(2) GlyRSs. The human pathogen eubacterium Campylobacter jejuni GlyRS (CjGlyRS) is an α(2)β(2) heterotetramer and is similar to Escherichia coli GlyRS; both are members of Class IIc AARSs. The two-step aminoacylation reaction of tetrameric GlyRSs requires the involvement of both α- and β-subunits. At present, the structure of the GlyRS α(2)β(2) class and the details of the enzymatic mechanism of this enzyme remain unknown. Here we report the crystal structures of the catalytic α-subunit of CjGlyRS and its complexes with ATP, and ATP and glycine. These structures provide detailed information on substrate binding and show evidence for a proposed mechanism for amino acid activation and the formation of the glycyl-adenylate intermediate for Class II AARSs.
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Affiliation(s)
- Kemin Tan
- Center for Structural Genomics of Infectious Diseases, University of Chicago, Chicago, IL 60637, USA
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Huang JG, Gao XJ, Li QZ, Lu LM, Liu R, Luo CC, Wang JL, Bin Q, Jin X. Proteomic analysis of the nuclear phosphorylated proteins in dairy cow mammary epithelial cells treated with estrogen. In Vitro Cell Dev Biol Anim 2012; 48:449-57. [PMID: 22806971 DOI: 10.1007/s11626-012-9531-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 06/21/2012] [Indexed: 01/27/2023]
Abstract
Estrogen regulates a variety of physiological processes, including mammary gland growth, morphogenesis of the mammary gland, proliferation and differentiation, and elevating the expression of milk proteins. Many nuclear phosphorylated proteins such as pStat5 and mTOR regulate milk protein synthesis. But the detail of milk protein synthesis controlled at the transcript level and posttranslational level is not well-known. To contribute to the understanding of the molecular mechanism underlying estrogen action on the dairy cow mammary epithelial cells (DCMECs), nuclear phosphorylated proteins regulated by estrogen in DCMECs were identified. Two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization/time of flight mass spectrometry were used to identify the changes of nuclear phosphorylated proteins in DCMECs treated with estrogen. Seven proteins were identified differentially up-expressed in DCMECs after 24-h estrogen exposure: including glycyl-tRNA synthetase, previously reported in milk protein synthesis of DCMECs, belonging to the class-II aminoacyl-tRNA synthetase family; proteins involved in other cellular functions, such as translation initiation factors, GTP-binding nuclear proteins, heat-shock proteins, and proteins belonging to ubiquitin-proteasome system. This screening reveals that estrogen influences the levels of nuclear phosphorylated proteins of DCMECs which opens new avenue for the study of the molecular mechanism linking to milk synthesis.
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Affiliation(s)
- Jian-Guo Huang
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University, Xiangfang District, Harbin, Heilongjiang Province, China
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Smirnova EV, Lakunina VA, Tarassov I, Krasheninnikov IA, Kamenski PA. Noncanonical functions of aminoacyl-tRNA synthetases. BIOCHEMISTRY (MOSCOW) 2012; 77:15-25. [PMID: 22339629 DOI: 10.1134/s0006297912010026] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Aminoacyl-tRNA synthetases, together with their main function of covalent binding of an amino acid to a corresponding tRNA, also perform many other functions. They take part in regulation of gene transcription, apoptosis, translation, and RNA splicing. Some of them function as cytokines or catalyze different reactions in living cells. Noncanonical functions can be mediated by additional domains of these proteins. On the other hand, some of the noncanonical functions are directly associated with the active center of the aminoacylation reaction. In this review we summarize recent data on the noncanonical functions of aminoacyl-tRNA synthetases and on the mechanisms of their action.
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Affiliation(s)
- E V Smirnova
- Department of Molecular Biology, Lomonosov Moscow State University, Moscow, Russia
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Wang J, Fang P, Schimmel P, Guo M. Side chain independent recognition of aminoacyl adenylates by the Hint1 transcription suppressor. J Phys Chem B 2012; 116:6798-805. [PMID: 22329685 PMCID: PMC3375047 DOI: 10.1021/jp212457w] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
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Human Hint1 suppresses specific gene transcription by
interacting with the transcription factor MITF in mast cells. Hint1
activity is connected to lysyl-tRNA synthetase (LysRS), a member of
the universal aminoacyl tRNA synthetase family that catalyzes specific
aminoacylation of their cognate tRNAs, through an aminoacyl adenylate
(aa-AMP) intermediate. During immune activation, LysRS produces a
side-product diadenosine tetraphosphate (Ap4A) from the
condensation of Lys-AMP with ATP. The pleiotropic signaling molecule
Ap4A then binds Hint1 to promote activation of MITF-target
gene transcription. Earlier work showed that Hint1 can also bind and
hydrolyze Lys-AMP, possibly to constrain Ap4A production.
Because Ap4A can result from condensation of other aa-AMP's
with ATP, the specificity of the Hint1 aa-AMP–hydrolysis activity
is of interest. Here we show that Hint1 has broad specificity for
adenylate hydrolysis, whose structural basis we revealed through high-resolution
structures of Hint1 in complex with three different aa-AMP analogues.
Hint1 recognizes only the common main chain of the aminoacyl moiety,
and has no contact with the aa side chain. The α-amino group
is anchored by a cation-pi interaction with Trp123 at the C-terminus
of Hint1. These results reveal the structural basis for the remarkable
adenylate surveillance activity of Hint1, to potentially control Ap4A levels in the cell.
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Affiliation(s)
- Jing Wang
- Department of Cancer Biology, The Scripps Research Institute, Scripps Florida, 130 Scripps Way, Jupiter, Florida 33458, USA
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Andreev DE, Hirnet J, Terenin IM, Dmitriev SE, Niepmann M, Shatsky IN. Glycyl-tRNA synthetase specifically binds to the poliovirus IRES to activate translation initiation. Nucleic Acids Res 2012; 40:5602-14. [PMID: 22373920 PMCID: PMC3384309 DOI: 10.1093/nar/gks182] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Adaptation to the host cell environment to efficiently take-over the host cell's machinery is crucial in particular for small RNA viruses like picornaviruses that come with only small RNA genomes and replicate exclusively in the cytosol. Their Internal Ribosome Entry Site (IRES) elements are specific RNA structures that facilitate the 5′ end-independent internal initiation of translation both under normal conditions and when the cap-dependent host protein synthesis is shut-down in infected cells. A longstanding issue is which host factors play a major role in this internal initiation. Here, we show that the functionally most important domain V of the poliovirus IRES uses tRNAGly anticodon stem–loop mimicry to recruit glycyl-tRNA synthetase (GARS) to the apical part of domain V, adjacent to the binding site of the key initiation factor eIF4G. The binding of GARS promotes the accommodation of the initiation region of the IRES in the mRNA binding site of the ribosome, thereby greatly enhancing the activity of the IRES at the step of the 48S initiation complex formation. Moonlighting functions of GARS that may be additionally needed for other events of the virus–host cell interaction are discussed.
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Affiliation(s)
- Dmitri E Andreev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Building 40, Moscow 119991, Russian Federation
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Fraga H, Fontes R. Enzymatic synthesis of mono and dinucleoside polyphosphates. Biochim Biophys Acta Gen Subj 2011; 1810:1195-204. [PMID: 21978831 DOI: 10.1016/j.bbagen.2011.09.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 09/09/2011] [Accepted: 09/19/2011] [Indexed: 01/08/2023]
Abstract
BACKGROUND Mono and dinucleoside polyphosphates (p(n)Ns and Np(n)Ns) exist in living organisms and induce diverse biological effects through interaction with intracellular and cytoplasmic membrane proteins. The source of these compounds is associated with secondary activities of a diverse group of enzymes. SCOPE OF REVIEW Here we discuss the mechanisms that can promote their synthesis at a molecular level. Although all the enzymes described in this review are able to catalyse the in vitro synthesis of Np(n)Ns (and/or p(n)N), it is not clear which ones are responsible for their in vivo accumulation. MAJOR CONCLUSIONS Despite the large amount of knowledge already available, important questions remain to be answered and a more complete understanding of p(n)Ns and Np(n)Ns synthesis mechanisms is required. With the possible exception of (GTP:GTP guanylyltransferase of Artemia), all enzymes able to catalyse the synthesis of p(n)Ns and Np(n)Ns are unspecific and the factors that can promote their synthesis relative to the canonical enzyme activities are unclear. GENERAL SIGNIFICANCE The fact that p(n)Ns and Np(n)Ns syntheses are promiscuous activities of housekeeping enzymes does not reduce its physiological or pathological importance. Here we resume the current knowledge regarding their enzymatic synthesis and point the open questions on the field.
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Affiliation(s)
- Hugo Fraga
- Department of Biochemistry, Universitat Autonoma de Barcelona, Spain
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Abstract
Many, if not most, enzymes can promiscuously catalyze reactions, or act on substrates, other than those for which they evolved. Here, we discuss the structural, mechanistic, and evolutionary implications of this manifestation of infidelity of molecular recognition. We define promiscuity and related phenomena and also address their generality and physiological implications. We discuss the mechanistic enzymology of promiscuity--how enzymes, which generally exert exquisite specificity, catalyze other, and sometimes barely related, reactions. Finally, we address the hypothesis that promiscuous enzymatic activities serve as evolutionary starting points and highlight the unique evolutionary features of promiscuous enzyme functions.
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Affiliation(s)
- Olga Khersonsky
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
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