1
|
Wortmann SB, Timal S, Venselaar H, Wintjes LT, Kopajtich R, Feichtinger RG, Onnekink C, Mühlmeister M, Brandt U, Smeitink JA, Veltman JA, Sperl W, Lefeber D, Pruijn G, Stojanovic V, Freisinger P, V Spronsen F, Derks TG, Veenstra-Knol HE, Mayr JA, Rötig A, Tarnopolsky M, Prokisch H, Rodenburg RJ. Biallelic variants in WARS2 encoding mitochondrial tryptophanyl-tRNA synthase in six individuals with mitochondrial encephalopathy. Hum Mutat 2017; 38:1786-1795. [PMID: 28905505 DOI: 10.1002/humu.23340] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 09/07/2017] [Accepted: 09/10/2017] [Indexed: 12/12/2022]
Abstract
Mitochondrial protein synthesis involves an intricate interplay between mitochondrial DNA encoded RNAs and nuclear DNA encoded proteins, such as ribosomal proteins and aminoacyl-tRNA synthases. Eukaryotic cells contain 17 mitochondria-specific aminoacyl-tRNA synthases. WARS2 encodes mitochondrial tryptophanyl-tRNA synthase (mtTrpRS), a homodimeric class Ic enzyme (mitochondrial tryptophan-tRNA ligase; EC 6.1.1.2). Here, we report six individuals from five families presenting with either severe neonatal onset lactic acidosis, encephalomyopathy and early death or a later onset, more attenuated course of disease with predominating intellectual disability. Respiratory chain enzymes were usually normal in muscle and fibroblasts, while a severe combined respiratory chain deficiency was found in the liver of a severely affected individual. Exome sequencing revealed rare biallelic variants in WARS2 in all affected individuals. An increase of uncharged mitochondrial tRNATrp and a decrease of mtTrpRS protein content were found in fibroblasts of affected individuals. We hereby define the clinical, neuroradiological, and metabolic phenotype of WARS2 defects. This confidently implicates that mutations in WARS2 cause mitochondrial disease with a broad spectrum of clinical presentation.
Collapse
Affiliation(s)
- Saskia B Wortmann
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria.,Institute of Human Genetics, Helmholtz Zentrum Munich, Neuherberg, Germany.,Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Sharita Timal
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.,Department of Neurology, Donders Center for Brain, Cognition, and Behavior, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hanka Venselaar
- Center for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Liesbeth T Wintjes
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Robert Kopajtich
- Institute of Human Genetics, Helmholtz Zentrum Munich, Neuherberg, Germany
| | - René G Feichtinger
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - Carla Onnekink
- Department of Biomolecular Chemistry, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.,Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Mareike Mühlmeister
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ulrich Brandt
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jan A Smeitink
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joris A Veltman
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.,Institute of Genetic Medicine, International Centre for Life, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Wolfgang Sperl
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - Dirk Lefeber
- Department of Neurology, Donders Center for Brain, Cognition, and Behavior, Translational Metabolic Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ger Pruijn
- Department of Biomolecular Chemistry, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.,Department of Biomolecular Chemistry, Institute for Molecules and Materials, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Vesna Stojanovic
- School of Medicine, University of Novi Sad, Novi Sad, Serbia.,Institute for Child and Youth Health Care of Vojvodina, Intensive Care Unit, Novi Sad, Serbia
| | - Peter Freisinger
- Children's Hospital, Klinikum am Steinenberg, Reutlingen, Germany
| | - Francjan V Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center of Groningen, Groningen, the Netherlands
| | - Terry Gj Derks
- Division of Metabolic Diseases, Beatrix Children's Hospital, University of Groningen, University Medical Center of Groningen, Groningen, the Netherlands
| | - Hermine E Veenstra-Knol
- Department of Genetics, University of Groningen, University Medical Center of Groningen, Groningen, the Netherlands
| | - Johannes A Mayr
- Department of Pediatrics, Salzburger Landeskliniken (SALK) and Paracelsus Medical University (PMU), Salzburg, Austria
| | - Agnes Rötig
- INSERM U1163, Université Paris Descartes - Sorbonne Paris Cité, Institut Imagine, Paris, France
| | - Mark Tarnopolsky
- Department of Pediatrics, Division of Neuromuscular and Neurometabolic Diseases, McMaster University Medical Center, Hamilton, Ontario, Canada
| | - Holger Prokisch
- Institute of Human Genetics, Helmholtz Zentrum Munich, Neuherberg, Germany.,Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Richard J Rodenburg
- Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| |
Collapse
|
2
|
Moutiez M, Schmitt E, Seguin J, Thai R, Favry E, Belin P, Mechulam Y, Gondry M. Unravelling the mechanism of non-ribosomal peptide synthesis by cyclodipeptide synthases. Nat Commun 2014; 5:5141. [DOI: 10.1038/ncomms6141] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 09/02/2014] [Indexed: 11/09/2022] Open
|
3
|
Moutiez M, Seguin J, Fonvielle M, Belin P, Jacques IB, Favry E, Arthur M, Gondry M. Specificity determinants for the two tRNA substrates of the cyclodipeptide synthase AlbC from Streptomyces noursei. Nucleic Acids Res 2014; 42:7247-58. [PMID: 24782519 PMCID: PMC4066775 DOI: 10.1093/nar/gku348] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Cyclodipeptide synthases (CDPSs) use two aminoacyl-tRNA substrates in a sequential ping-pong mechanism to form a cyclodipeptide. The crystal structures of three CDPSs have been determined and all show a Rossmann-fold domain similar to the catalytic domain of class-I aminoacyl-tRNA synthetases (aaRSs). Structural features and mutational analyses however suggest that CDPSs and aaRSs interact differently with their tRNA substrates. We used AlbC from Streptomyces noursei that mainly produces cyclo(l-Phe-l-Leu) to investigate the interaction of a CDPS with its substrates. We demonstrate that Phe-tRNAPhe is the first substrate accommodated by AlbC. Its binding to AlbC is dependent on basic residues located in the helix α4 that form a basic patch at the surface of the protein. AlbC does not use all of the Leu-tRNALeu isoacceptors as a second substrate. We show that the G1-C72 pair of the acceptor stem is essential for the recognition of the second substrate. Substitution of D163 located in the loop α6–α7 or D205 located in the loop β6–α8 affected Leu-tRNALeu isoacceptors specificity, suggesting the involvement of these residues in the binding of the second substrate. This is the first demonstration that the two substrates of CDPSs are accommodated in different binding sites.
Collapse
MESH Headings
- Bacterial Proteins/chemistry
- Bacterial Proteins/metabolism
- Binding Sites
- Peptide Synthases/chemistry
- Peptide Synthases/metabolism
- RNA, Transfer, Amino Acyl/chemistry
- RNA, Transfer, Amino Acyl/metabolism
- RNA, Transfer, Leu/chemistry
- RNA, Transfer, Leu/metabolism
- RNA, Transfer, Phe/chemistry
- RNA, Transfer, Phe/metabolism
- Streptomyces/enzymology
- Substrate Specificity
Collapse
Affiliation(s)
- Mireille Moutiez
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| | - Jérôme Seguin
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| | - Matthieu Fonvielle
- INSERM, U1138, LRMA, Equipe 12 du Centre de Recherche des Cordeliers, Paris 75006, France Université Pierre et Marie Curie, UMR S 1138, Paris, France Université Paris Descartes, Sorbonne Paris Cité, UMR S 1138, Paris, France
| | - Pascal Belin
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| | - Isabelle Béatrice Jacques
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| | - Emmanuel Favry
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| | - Michel Arthur
- INSERM, U1138, LRMA, Equipe 12 du Centre de Recherche des Cordeliers, Paris 75006, France Université Pierre et Marie Curie, UMR S 1138, Paris, France Université Paris Descartes, Sorbonne Paris Cité, UMR S 1138, Paris, France
| | - Muriel Gondry
- Service d'Ingénierie Moléculaire des Protéines, iBiTec-S, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), 91191 Gif-sur-Yvette Cedex, France
| |
Collapse
|
4
|
Physicochemical analysis of rotavirus segment 11 supports a 'modified panhandle' structure and not the predicted alternative tRNA-like structure (TRLS). Arch Virol 2013; 159:235-48. [PMID: 23942952 PMCID: PMC3906528 DOI: 10.1007/s00705-013-1802-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/19/2013] [Indexed: 11/05/2022]
Abstract
Rotaviruses are a major cause of acute gastroenteritis, which is often fatal in infants. The viral genome consists of 11 double-stranded RNA segments, but little is known about their cis-acting sequences and structural elements. Covariation studies and phylogenetic analysis exploring the potential structure of RNA11 of rotaviruses suggested that, besides the previously predicted “modified panhandle” structure, the 5’ and 3’ termini of one of the isoforms of the bovine rotavirus UKtc strain may interact to form a tRNA-like structure (TRLS). Such TRLSs have been identified in RNAs of plant viruses, where they are important for enhancing replication and packaging. However, using tRNA mimicry assays (in vitro aminoacylation and 3’- adenylation), we found no biochemical evidence for tRNA-like functions of RNA11. Capping, synthetic 3’ adenylation and manipulation of divalent cation concentrations did not change this finding. NMR studies on a 5’- and 3’-deletion construct of RNA11 containing the putative intra-strand complementary sequences supported a predominant panhandle structure and did not conform to a cloverleaf fold despite the strong evidence for a predicted structure in this conserved region of the viral RNA. Additional viral or cellular factors may be needed to stabilise it into a form with tRNA-like properties.
Collapse
|
5
|
Importance of single molecular determinants in the fidelity of expanded genetic codes. Proc Natl Acad Sci U S A 2011; 108:1320-5. [PMID: 21224416 DOI: 10.1073/pnas.1012276108] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The site-selective encoding of noncanonical amino acids (NAAs) is a powerful technique for the installation of novel chemical functional groups in proteins. This is often achieved by recoding a stop codon and requires two additional components: an evolved aminoacyl tRNA synthetase (AARS) and a cognate tRNA. Analysis of the most successful AARSs reveals common characteristics. The highest fidelity NAA systems derived from the Methanocaldococcus jannaschii tyrosyl AARS feature specific mutations to two residues reported to interact with the hydroxyl group of the substrate tyrosine. We demonstrate that the restoration of just one of these determinants for amino acid specificity results in the loss of fidelity as the evolved AARSs become noticeably promiscuous. These results offer a partial explanation of a recently retracted strategy for the synthesis of glycoproteins. Similarly, we reinvestigated a tryptophanyl AARS reported to allow the site-selective incorporation of 5-hydroxy tryptophan within mammalian cells. In multiple experiments, the enzyme displayed elements of promiscuity despite its previous characterization as a high fidelity enzyme. Given the many similarities of the TyrRSs and TrpRSs reevaluated here, our findings can be largely combined, and in doing so they reinforce the long-established central dogma regarding the molecular basis by which these enzymes contribute to the fidelity of translation. Thus, our view is that the central claims of fidelity reported in several NAA systems remain unproven and unprecedented.
Collapse
|
6
|
Guo LT, Chen XL, Zhao BT, Shi Y, Li W, Xue H, Jin YX. Human tryptophanyl-tRNA synthetase is switched to a tRNA-dependent mode for tryptophan activation by mutations at V85 and I311. Nucleic Acids Res 2007; 35:5934-43. [PMID: 17726052 PMCID: PMC2034488 DOI: 10.1093/nar/gkm633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
For most aminoacyl-tRNA synthetases (aaRS), their cognate tRNA is not obligatory to catalyze amino acid activation, with the exception of four class I (aaRS): arginyl-tRNA synthetase, glutamyl-tRNA synthetase, glutaminyl-tRNA synthetase and class I lysyl-tRNA synthetase. Furthermore, for arginyl-, glutamyl- and glutaminyl-tRNA synthetase, the integrated 3' end of the tRNA is necessary to activate the ATP-PPi exchange reaction. Tryptophanyl-tRNA synthetase is a class I aaRS that catalyzes tryptophan activation in the absence of its cognate tRNA. Here we describe mutations located at the appended β1–β2 hairpin and the AIDQ sequence of human tryptophanyl-tRNA synthetase that switch this enzyme to a tRNA-dependent mode in the tryptophan activation step. For some mutant enzymes, ATP-PPi exchange activity was completely lacking in the absence of tRNATrp, which could be partially rescued by adding tRNATrp, even if it had been oxidized by sodium periodate. Therefore, these mutant enzymes have strong similarity to arginyl-tRNA synthetase, glutaminyl-tRNA synthetase and glutamyl-tRNA synthetase in their mode of amino acid activation. The results suggest that an aaRS that does not normally require tRNA for amino acid activation can be switched to a tRNA-dependent mode.
Collapse
Affiliation(s)
- Li-Tao Guo
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - Xiang-Long Chen
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - Bo-Tao Zhao
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - Yi Shi
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - Wei Li
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - Hong Xue
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
| | - You-Xin Jin
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031 and Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kwoloon, Hong Kong, China
- *To whom correspondence should be addressed. 0086 21 549212220086 21 5492 1011
| |
Collapse
|
7
|
Yang XL, Otero FJ, Ewalt KL, Liu J, Swairjo MA, Köhrer C, RajBhandary UL, Skene RJ, McRee DE, Schimmel P. Two conformations of a crystalline human tRNA synthetase-tRNA complex: implications for protein synthesis. EMBO J 2006; 25:2919-29. [PMID: 16724112 PMCID: PMC1500858 DOI: 10.1038/sj.emboj.7601154] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Accepted: 04/27/2006] [Indexed: 11/09/2022] Open
Abstract
Aminoacylation of tRNA is the first step of protein synthesis. Here, we report the co-crystal structure of human tryptophanyl-tRNA synthetase and tRNATrp. This enzyme is reported to interact directly with elongation factor 1alpha, which carries charged tRNA to the ribosome. Crystals were generated from a 50/50% mixture of charged and uncharged tRNATrp. These crystals captured two conformations of the complex, which are nearly identical with respect to the protein and a bound tryptophan. They are distinguished by the way tRNA is bound. In one, uncharged tRNA is bound across the dimer, with anticodon and acceptor stem interacting with separate subunits. In this cross-dimer tRNA complex, the class I enzyme has a class II-like tRNA binding mode. This structure accounts for biochemical investigations of human TrpRS, including species-specific charging. In the other conformation, presumptive aminoacylated tRNA is bound only by the anticodon, the acceptor stem being free and having space to interact precisely with EF-1alpha, suggesting that the product of aminoacylation can be directly handed off to EF-1alpha for the next step of protein synthesis.
Collapse
Affiliation(s)
- Xiang-Lei Yang
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Buddha MR, Crane BR. Structures of tryptophanyl-tRNA synthetase II from Deinococcus radiodurans bound to ATP and tryptophan. Insight into subunit cooperativity and domain motions linked to catalysis. J Biol Chem 2005; 280:31965-73. [PMID: 15998643 DOI: 10.1074/jbc.m501568200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
An auxiliary tryptophanyl tRNA synthetase (drTrpRS II) that interacts with nitric-oxide synthase in the radiation-resistant bacterium Deinococcus radiodurans charges tRNA with tryptophan and 4-nitrotryptophan, a specific nitration product of nitric-oxide synthase. Crystal structures of drTrpRS II, empty of ligands or bound to either Trp or ATP, reveal that drTrpRS II has an overall structure similar to standard bacterial TrpRSs but undergoes smaller amplitude motions of the helical tRNA anti-codon binding (TAB) domain on binding substrates. TAB domain loop conformations that more closely resemble those of human TrpRS than those of Bacillus stearothermophilus TrpRS (bsTrpRS) indicate different modes of tRNA recognition by subclasses of bacterial TrpRSs. A compact state of drTrpRS II binds ATP, from which only minimal TAB domain movement is necessary to bring nucleotide in contact with Trp. However, the signature KMSKS loop of class I synthetases does not completely engage the ATP phosphates, and the adenine ring is not well ordered in the absence of Trp. Thus, progression of the KMSKS loop to a high energy conformation that stages acyl-adenylation requires binding of both substrates. In an asymmetric drTrpRS II dimer, the closed subunit binds ATP, whereas the open subunit binds Trp. A crystallographically symmetric dimer binds no ligands. Half-site reactivity for Trp binding is confirmed by thermodynamic measurements and explained by an asymmetric shift of the dimer interface toward the occupied active site. Upon Trp binding, Asp68 propagates structural changes between subunits by switching its hydrogen bonding partner from dimer interface residue Tyr139 to active site residue Arg30. Since TrpRS IIs are resistant to inhibitors of standard TrpRSs, and pathogens contain drTrpRS II homologs, the structure of drTrpRS II provides a framework for the design of potentially useful antibiotics.
Collapse
Affiliation(s)
- Madhavan R Buddha
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, USA
| | | |
Collapse
|
9
|
Jia J, Chen XL, Guo LT, Yu YD, Ding JP, Jin YX. Residues Lys-149 and Glu-153 Switch the Aminoacylation of tRNATrp in Bacillus subtilis. J Biol Chem 2004; 279:41960-5. [PMID: 15280378 DOI: 10.1074/jbc.m401937200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Tryptophanyl-tRNA synthetase (TrpRS) consists of two identical subunits that induce the cross-subunit binding mode of tRNA(Trp). It has been shown that eubacterial and eukaryotic TrpRSs cannot efficiently cross-aminoacylate the corresponding tRNA(Trp). Although the identity elements in tRNA(Trp) that confer the species-specific recognition have been identified, the corresponding elements in TrpRS have not yet been reported. In this study two residues, Lys-149 and Glu-153, were identified as being crucial for the accurate recognition of tRNA(Trp). These residues reside adjacent to the binding pocket for Trp-AMP and show phylogenic diversities in the charge on their side chains between eubacteria and eukaryotes. Single mutagenesis at Lys-149 or Glu-153 reduced the activity of TrpRS in the activation of Trp. The reduction was less than that caused by the double mutant WBHA (K149D/E153R). It is unusual that E153G had no detectable activity in the activation of Trp unless tRNA(Trp) was added to the reaction. In addition, we successfully switched the species specificity of Bacillus subtilis TrpRS recognition of tRNA(Trp). The affinity of WBHA, K149E and E153K to human tRNA(Trp) was 31-, 13.5-, and 12.9-fold greater than that of wild type B. subtilis TrpRS, respectively. Indeed WBHA and E153K were found to prefer genuine human tRNA(Trp) to their cognate eubacteria tRNA(Trp).
Collapse
Affiliation(s)
- Jie Jia
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai 200031, China
| | | | | | | | | | | |
Collapse
|
10
|
Kise Y, Lee SW, Park SG, Fukai S, Sengoku T, Ishii R, Yokoyama S, Kim S, Nureki O. A short peptide insertion crucial for angiostatic activity of human tryptophanyl-tRNA synthetase. Nat Struct Mol Biol 2004; 11:149-56. [PMID: 14730354 DOI: 10.1038/nsmb722] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2003] [Accepted: 12/15/2003] [Indexed: 11/08/2022]
Abstract
Human tryptophanyl-tRNA synthetase (TrpRS) is secreted into the extracellular region of vascular endothelial cells. The splice variant form (mini TrpRS) functions in vascular endothelial cell apoptosis as an angiostatic cytokine. In contrast, the closely related human tyrosyl-tRNA synthetase (TyrRS) functions as an angiogenic cytokine in its truncated form (mini TyrRS). Here, we determined the crystal structure of human mini TrpRS at a resolution of 2.3 A and compared the structure with those of prokaryotic TrpRS and human mini TyrRS. Deletion of the tRNA anticodon-binding (TAB) domain insertion, consisting of eight residues in the human TrpRS, abolished the enzyme's apoptotic activity for endothelial cells, whereas its translational catalysis and cell-binding activities remained unchanged. Thus, we have identified the inserted peptide motif that activates the angiostatic signaling.
Collapse
Affiliation(s)
- Yoshiaki Kise
- Department of Biophysics and Biochemistry, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Yu Y, Liu Y, Shen N, Xu X, Xu F, Jia J, Jin Y, Arnold E, Ding J. Crystal structure of human tryptophanyl-tRNA synthetase catalytic fragment: insights into substrate recognition, tRNA binding, and angiogenesis activity. J Biol Chem 2003; 279:8378-88. [PMID: 14660560 DOI: 10.1074/jbc.m311284200] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human tryptophanyl-tRNA synthetase (hTrpRS) produces a full-length and three N terminus-truncated forms through alternative splicing and proteolysis. The shortest fragment that contains the aminoacylation catalytic fragment (T2-hTrpRS) exhibits the most potent angiostatic activity. We report here the crystal structure of T2-hTrpRS at 2.5 A resolution, which was solved using the multi-wavelength anomalous diffraction method. T2-hTrpRS shares a very low sequence homology of 22% with Bacillus stearothermophilus TrpRS (bTrpRS); however, their overall structures are strikingly similar. Structural comparison of T2-hTrpRS with bTrpRS reveals substantial structural differences in the substrate-binding pocket and at the entrance to the pocket that play important roles in substrate binding and tRNA binding. T2-hTrpRS has a wide opening to the active site and adopts a compact conformation similar to the closed conformation of bTrpRS. These results suggest that mammalian and bacterial TrpRSs might use different mechanisms to recognize the substrate. Modeling studies indicate that tRNA binds with the dimeric enzyme and interacts primarily with the connective polypeptide 1 of hTrpRS via its acceptor arm and the alpha-helical domain of hTrpRS via its anticodon loop. Our results also suggest that the angiostatic activity is likely located at the alpha-helical domain, which resembles the short chain cytokines.
Collapse
Affiliation(s)
- Yadong Yu
- Key Laboratory of Proteomics and State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Zúñiga R, Salazar J, Canales M, Orellana O. A dispensable peptide from Acidithiobacillus ferrooxidans tryptophanyl-tRNA synthetase affects tRNA binding. FEBS Lett 2002; 532:387-90. [PMID: 12482597 DOI: 10.1016/s0014-5793(02)03720-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The activation domain of class I aminoacyl-tRNA synthetases, which contains the Rossmann fold and the signature sequences HIGH and KMSKS, is generally split into two halves by the connective peptides (CP1, CP2) whose amino acid sequences are idiosyncratic. CP1 has been shown to participate in the binding of tRNA as well as the editing of the reaction intermediate aminoacyl-AMP or the aminoacyl-tRNA. No function has been assigned to CP2. The amino acid sequence of Acidithiobacillus ferrooxidans TrpRS was predicted from the genome sequence. Protein sequence alignments revealed that A. ferrooxidans TrpRS contains a 70 amino acids long CP2 that is not found in any other bacterial TrpRS. However, a CP2 in the same relative position was found in the predicted sequence of several archaeal TrpRSs. A. ferrooxidans TrpRS is functional in vivo in Escherichia coli. A deletion mutant of A. ferrooxidans trpS lacking the coding region of CP2 was constructed. The in vivo activity of the mutant TrpRS in E. coli, as well as the kinetic parameters of the in vitro activation of tryptophan by ATP, were not altered by the deletion. However, the K(m) value for tRNA was seven-fold higher upon deletion, reducing the efficiency of aminoacylation. Structural modeling suggests that CP2 binds to the inner corner of the L shape of tRNA.
Collapse
Affiliation(s)
- Roberto Zúñiga
- Programa de Biología Celular y Molecular, ICBM, Facultad de Medicina, Universidad de Chile, Casilla 70086, 838-0453, Santiago, Chile
| | | | | | | |
Collapse
|