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Dulic M, Godinic-Mikulcic V, Kekez M, Evic V, Rokov-Plavec J. Protein-Protein Interactions of Seryl-tRNA Synthetases with Emphasis on Human Counterparts and Their Connection to Health and Disease. Life (Basel) 2024; 14:124. [PMID: 38255739 PMCID: PMC10817482 DOI: 10.3390/life14010124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
Seryl-tRNA synthetases (SerRSs), members of the aminoacyl-tRNA synthetase family, interact with diverse proteins, enabling SerRSs to enhance their role in the translation of the genetic message or to perform alternative functions in cellular processes beyond translation. Atypical archaeal SerRS interacts with arginyl-tRNA synthetase and proteins of the ribosomal P-stalk to optimize translation through tRNA channeling. The complex between yeast SerRS and peroxin Pex21p provides a connection between translation and peroxisome function. The partnership between Arabidopsis SerRS and BEN1 indicates a link between translation and brassinosteroid metabolism and may be relevant in plant stress response mechanisms. In Drosophila, the unusual heterodimeric mitochondrial SerRS coordinates mitochondrial translation and replication via interaction with LON protease. Evolutionarily conserved interactions of yeast and human SerRSs with m3C32 tRNA methyltransferases indicate coordination between tRNA modification and aminoacylation in the cytosol and mitochondria. Human cytosolic SerRS is a cellular hub protein connecting translation to vascular development, angiogenesis, lipogenesis, and telomere maintenance. When translocated to the nucleus, SerRS acts as a master negative regulator of VEGFA gene expression. SerRS alone or in complex with YY1 and SIRT2 competes with activating transcription factors NFκB1 and c-Myc, resulting in balanced VEGFA expression important for proper vascular development and angiogenesis. In hypoxia, SerRS phosphorylation diminishes its binding to the VEGFA promoter, while the lack of nutrients triggers SerRS glycosylation, reducing its nuclear localization. Additionally, SerRS binds telomeric DNA and cooperates with the shelterin protein POT1 to regulate telomere length and cellular senescence. As an antitumor and antiangiogenic factor, human cytosolic SerRS appears to be a promising drug target and therapeutic agent for treating cancer, cardiovascular diseases, and possibly obesity and aging.
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Affiliation(s)
| | | | | | | | - Jasmina Rokov-Plavec
- Division of Biochemistry, Department of Chemistry, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (M.D.); (V.G.-M.); (M.K.); (V.E.)
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2
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Controlled processivity in glycosyltransferases: A way to expand the enzymatic toolbox. Biotechnol Adv 2023; 63:108081. [PMID: 36529206 DOI: 10.1016/j.biotechadv.2022.108081] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/20/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022]
Abstract
Glycosyltransferases (GT) catalyse the biosynthesis of complex carbohydrates which are the most abundant group of molecules in nature. They are involved in several key mechanisms such as cell signalling, biofilm formation, host immune system invasion or cell structure and this in both prokaryotic and eukaryotic cells. As a result, research towards complete enzyme mechanisms is valuable to understand and elucidate specific structure-function relationships in this group of molecules. In a next step this knowledge could be used in GT protein engineering, not only for rational drug design but also for multiple biotechnological production processes, such as the biosynthesis of hyaluronan, cellooligosaccharides or chitooligosaccharides. Generation of these poly- and/or oligosaccharides is possible due to a common feature of several of these GTs: processivity. Enzymatic processivity has the ability to hold on to the growing polymer chain and some of these GTs can even control the number of glycosyl transfers. In a first part, recent advances in understanding the mechanism of various processive enzymes are discussed. To this end, an overview is given of possible engineering strategies for the purpose of new industrial and fundamental applications. In the second part of this review, we focused on specific chain length-controlling mechanisms, i.e., key residues or conserved regions, and this for both eukaryotic and prokaryotic enzymes.
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Comparative QM/MM study on the inhibition mechanism of β-Hydroxynorvaline to Threonyl-tRNA synthetase. J Mol Graph Model 2022; 115:108224. [DOI: 10.1016/j.jmgm.2022.108224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/26/2022] [Accepted: 05/13/2022] [Indexed: 11/18/2022]
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Wang ZS, Zhou HC, Wei CY, Wang ZH, Hao X, Zhang LH, Li JZ, Wang ZL, Wang H. Global survey of miRNAs and tRNA-derived small RNAs from the human parasitic protist Trichomonas vaginalis. Parasit Vectors 2021; 14:87. [PMID: 33514387 PMCID: PMC7844918 DOI: 10.1186/s13071-020-04570-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/28/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Small non-coding RNAs play critical regulatory roles in post-transcription. However, their characteristics in Trichomonas vaginalis, the causative agent of human sexually transmitted trichomoniasis, still remain to be determined. METHODS Small RNA transcriptomes from Trichomonas trophozoites were deep sequenced using the Illumina NextSeq 500 system and comprehensively analyzed to identify Trichomonas microRNAs (miRNAs) and transfer RNA (tRNA)-derived small RNAs (tsRNAs). The tsRNA candidates were confirmed by stem-loop quantitative reverse transcription-PCR, and motifs to guide the cleavage of tsRNAs were predicted using the GLAM2 algorithm. RESULTS The miRNAs were found to be present in T. vaginalis but at an extremely low abundance (0.0046%). Three categories of endogenous Trichomonas tsRNAs were identified, namely 5'tritsRNAs, mid-tritsRNAs and 3'tritsRNAs, with the 5'tritsRNAs constituting the dominant category (67.63%) of tsRNAs. Interestingly, the cleavage site analysis verified both conventional classes of tRNA-derived fragments (tRFs) and tRNA-halves in tritsRNAs, indicating the expression of tRNA-halves in the non-stress condition. A total of 25 tritsRNAs were experimentally confirmed, accounting for 78.1% of all tested candidates. Three motifs were predicted to guide the production of tritsRNAs. The results prove the expression of tRFs and tRNA-halves in the T. vaginalis transcriptome. CONCLUSIONS This is the first report of genome-wide investigation of small RNAs, particularly tsRNAs and miRNAs, from Trichomonas parasites. Our findings demonstrate the expression profile of tsRNAs in T. vaginalis, while miRNA was barely detected. These results may promote further research aimed at gaining a better understanding of the evolution of small non-coding RNA in T. vaginalis and their functions in the pathogenesis of trichomoniasis.
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Affiliation(s)
- Zhen-Sheng Wang
- Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, #5 Dong Dan San Tiao, Beijing, 100005, People's Republic of China.,NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
| | - Hong-Chang Zhou
- School of Medicine, Huzhou University and Huzhou Central Hospital, Huzhou, 313000, Zhejiang province, China
| | - Chun-Yan Wei
- Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, #5 Dong Dan San Tiao, Beijing, 100005, People's Republic of China
| | - Zhi-Hua Wang
- Department of Immunology, Guilin Medical University, Guilin, 541000, Guangxi province, China
| | - Xiao Hao
- Blood Chamber, Blood Station of Jinan, Jinan, 250000, Shandong province, China
| | - Lian-Hui Zhang
- Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, #5 Dong Dan San Tiao, Beijing, 100005, People's Republic of China
| | - Jing-Zhong Li
- NHC Key Laboratory of Echinococcosis Prevention and Control, #21 linkuo North Road, Chengguan District, Lhasa, 850000, Tibet Autonomous Region, People's Republic of China
| | - Zeng-Lei Wang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
| | - Heng Wang
- Department of Microbiology and Parasitology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, #5 Dong Dan San Tiao, Beijing, 100005, People's Republic of China.
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5
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Khan K, Baleanu-Gogonea C, Willard B, Gogonea V, Fox PL. 3-Dimensional architecture of the human multi-tRNA synthetase complex. Nucleic Acids Res 2020; 48:8740-8754. [PMID: 32644155 PMCID: PMC7470956 DOI: 10.1093/nar/gkaa569] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 06/08/2020] [Accepted: 07/06/2020] [Indexed: 11/24/2022] Open
Abstract
In mammalian cells, eight cytoplasmic aminoacyl-tRNA synthetases (AARS), and three non-synthetase proteins, reside in a large multi-tRNA synthetase complex (MSC). AARSs have critical roles in interpretation of the genetic code during protein synthesis, and in non-canonical functions unrelated to translation. Nonetheless, the structure and function of the MSC remain unclear. Partial or complete crystal structures of all MSC constituents have been reported; however, the structure of the holo-MSC has not been resolved. We have taken advantage of cross-linking mass spectrometry (XL-MS) and molecular docking to interrogate the three-dimensional architecture of the MSC in human HEK293T cells. The XL-MS approach uniquely provides structural information on flexibly appended domains, characteristic of nearly all MSC constituents. Using the MS-cleavable cross-linker, disuccinimidyl sulfoxide, inter-protein cross-links spanning all MSC constituents were observed, including cross-links between eight protein pairs not previously known to interact. Intra-protein cross-links defined new structural relationships between domains in several constituents. Unexpectedly, an asymmetric AARS distribution was observed featuring a clustering of tRNA anti-codon binding domains on one MSC face. Possibly, the non-uniform localization improves efficiency of delivery of charged tRNA’s to an interacting ribosome during translation. In summary, we show a highly compact, 3D structural model of the human holo-MSC.
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Affiliation(s)
- Krishnendu Khan
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | | | - Belinda Willard
- Lerner Research Institute Proteomics and Metabolomics Core, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
| | - Valentin Gogonea
- Department of Chemistry, Cleveland State University, Cleveland, OH 44115, USA
| | - Paul L Fox
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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Abstract
Extracellular polysaccharides and glycoproteins of pathogenic bacteria assist in adherence, autoaggregation, biofilm formation, and host immune system evasion. As a result, considerable research in the field of glycobiology is dedicated to study the composition and function of glycans associated with virulence, as well as the enzymes involved in their biosynthesis with the aim to identify novel antibiotic targets. Especially, insights into the enzyme mechanism, substrate binding, and transition-state structures are valuable as a starting point for rational inhibitor design. An intriguing aspect of enzymes that generate or process polysaccharides and glycoproteins is the level of processivity. The existence of enzymatic processivity reflects the need for regulation of the final glycan/glycoprotein length and structure, depending on the role they perform. In this Review, we describe the currently reported examples of various processive enzymes involved in polymerization and transfer of sugar moieties, predominantly in bacterial pathogens, with a focus on the biochemical methods, to showcase the importance of studying processivity for understanding the mechanism.
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Affiliation(s)
- Liubov Yakovlieva
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Marthe T. C. Walvoort
- Stratingh Institute for Chemistry, University of Groningen, 9747 AG Groningen, The Netherlands
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7
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Metazoan tsRNAs: Biogenesis, Evolution and Regulatory Functions. Noncoding RNA 2019; 5:ncrna5010018. [PMID: 30781726 PMCID: PMC6468576 DOI: 10.3390/ncrna5010018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 01/30/2019] [Accepted: 02/12/2019] [Indexed: 12/15/2022] Open
Abstract
Transfer RNA-derived small RNAs (tsRNAs) are an emerging class of regulatory non-coding RNAs that play important roles in post-transcriptional regulation across a variety of biological processes. Here, we review the recent advances in tsRNA biogenesis and regulatory functions from the perspectives of functional and evolutionary genomics, with a focus on the tsRNA biology of Drosophila. We first summarize our current understanding of the biogenesis mechanisms of different categories of tsRNAs that are generated under physiological or stressed conditions. Next, we review the conservation patterns of tsRNAs in all domains of life, with an emphasis on the conservation of tsRNAs between two Drosophila species. Then, we elaborate the currently known regulatory functions of tsRNAs in mRNA translation that are independent of, or dependent on, Argonaute (AGO) proteins. We also highlight some issues related to the fundamental biology of tsRNAs that deserve further study.
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8
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Crnković A, Čavužić M, Godinić-Mikulčić V, Anderluh G, Weygand-Đurašević I, Gruić-Sovulj I. An archaeal aminoacyl-tRNA synthetase complex for improved substrate quality control. Biochimie 2017; 147:36-45. [PMID: 29273296 DOI: 10.1016/j.biochi.2017.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 12/17/2017] [Indexed: 10/18/2022]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) decode genetic information by coupling tRNAs with cognate amino acids. In the archaeon Methanothermobacter thermautotrophicus arginyl- and seryl-tRNA synthetase (ArgRS and SerRS, respectively) form a complex which enhances serylation and facilitates tRNASer recycling through its association with the ribosome. Yet, the way by which complex formation participates in Arg-tRNAArg synthesis is still unresolved. Here we utilized pull down and surface plasmon resonance experiments with truncated ArgRS variants to demonstrate that ArgRS uses its N-terminal domain to establish analogous interactions with both SerRS and cognate tRNAArg, providing a rationale for the lack of detectable SerRS•[ArgRS•tRNAArg] complex. In contrast, stable ternary ArgRS•[SerRS•tRNASer] complex was easily detected supporting the model wherein ArgRS operates in serylation by modulating SerRS affinity toward tRNASer. We also found that the interaction with SerRS suppresses arginylation of unmodified tRNAArg by ArgRS, which, by itself, does not discriminate against tRNAArg substrates lacking posttranscriptional modifications. Hence, there is a fundamentally different participation of the protein partners in Arg-tRNA and Ser-tRNA synthesis. Propensity of the ArgRS•SerRS complex to exclude unmodified tRNAs from translation leads to an attractive hypothesis that SerRS•ArgRS complex might act in vivo as a safeguarding switch that improves translation accuracy.
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Affiliation(s)
- Ana Crnković
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia.
| | - Mirela Čavužić
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia
| | - Vlatka Godinić-Mikulčić
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia
| | - Gregor Anderluh
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia; Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
| | - Ivana Weygand-Đurašević
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia
| | - Ita Gruić-Sovulj
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia.
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9
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Keam SP, Sobala A, Ten Have S, Hutvagner G. tRNA-Derived RNA Fragments Associate with Human Multisynthetase Complex (MSC) and Modulate Ribosomal Protein Translation. J Proteome Res 2016; 16:413-420. [PMID: 27936807 DOI: 10.1021/acs.jproteome.6b00267] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The functionality of small RNAs from abundant species of "housekeeping" noncoding RNAs (e.g., rRNA, tRNA, snRNA, snoRNA, etc.) remains a highly studied topic. The current state of research on short RNAs derived from transfer RNA (tRNA), called tRNA-derived fragments (tRFs), has been restricted largely to expression studies and limited functional studies. 5' tRFs are known translational inhibitors in mammalian cells, yet little is known about their functionality. Here we report on the first experimental evidence of the tRF protein interactome, identifying the mammalian multisynthetase complex as the primary interactor of the 5' tRF Gln19. We also present proteome-wide SILAC evidence that 5' tRFs increase ribosomal and poly(A)-binding protein translation.
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Affiliation(s)
- Simon P Keam
- Centre for Health Technologies, Faculty of Engineering and Information Technology, University of Technology Sydney , Ultimo 2007, Australia
| | - Andrew Sobala
- Wellcome Trust Centre for Gene Regulation and Expression, University of Dundee , Dundee DD1 4HN, United Kingdom
| | - Sara Ten Have
- Wellcome Trust Centre for Gene Regulation and Expression, University of Dundee , Dundee DD1 4HN, United Kingdom
| | - Gyorgy Hutvagner
- Centre for Health Technologies, Faculty of Engineering and Information Technology, University of Technology Sydney , Ultimo 2007, Australia
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10
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Arif A, Jia J, Halawani D, Fox PL. Experimental approaches for investigation of aminoacyl tRNA synthetase phosphorylation. Methods 2016; 113:72-82. [PMID: 27729295 DOI: 10.1016/j.ymeth.2016.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 02/04/2023] Open
Abstract
Phosphorylation of many aminoacyl tRNA synthetases (AARSs) has been recognized for decades, but the contribution of post-translational modification to their primary role in tRNA charging and decryption of genetic code remains unclear. In contrast, phosphorylation is essential for performance of diverse noncanonical functions of AARSs unrelated to protein synthesis. Phosphorylation of glutamyl-prolyl tRNA synthetase (EPRS) has been investigated extensively in our laboratory for more than a decade, and has served as an archetype for studies of other AARSs. EPRS is a constituent of the IFN-γ-activated inhibitor of translation (GAIT) complex that directs transcript-selective translational control in myeloid cells. Stimulus-dependent phosphorylation of EPRS is essential for its release from the parental multi-aminoacyl tRNA synthetase complex (MSC), for binding to other GAIT complex proteins, and for regulating the binding to target mRNAs. Importantly, phosphorylation is the common driving force for the context- and stimulus-dependent release, and non-canonical activity, of other AARSs residing in the MSC, for example, lysyl tRNA synthetase (KARS). Here, we describe the concepts and experimental methodologies we have used to investigate the influence of phosphorylation on the structure and function of EPRS. We suggest that application of these approaches will help to identify new functional phosphorylation event(s) in other AARSs and elucidate their possible roles in noncanonical activities.
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Affiliation(s)
- Abul Arif
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Jie Jia
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Dalia Halawani
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Paul L Fox
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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Mitra S, Samadder A, Das P, Das S, Dasgupta M, Chakrabarti J. Decrypting ENCODEd epigenetic marks of human tRN-A-RS genes in normal, stem and cancer cell lines. J Biomol Struct Dyn 2016; 35:2759-2771. [PMID: 27659686 DOI: 10.1080/07391102.2016.1240107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Screening large-scale ENCODE data of 625 cytoplasmic transfer RNA (tRNAs) and 37 aminoacyl tRNA synthetase (AARSs) human genes, we deconstruct the array of relations between 10 histone marks affecting 15 chromatin states; their tissue specificity and variations and interchange amongst normal, cancerous and stem cells. The histone marks of RNA Pol II transcribed AARS genes share, but also contrast with that on RNA Pol III transcribed tRNA genes. tRNAs with identical/similar sequences may be in significantly varying states even within the same cell line; the chromatin scaffold, where the tRNA gene resides, is the key determinant. Hepatocellular carcinoma cell line has dominant H3K27me3, and singular clustering of other marks. Leukaemic cell line has hyperactive genes. The quiescence of the stem cells is encoded in the markers. Leaving aside the important exceptions in stem cells and elsewhere, tRNAs with cove scores above 50 have active markers and precise sets of transcription factors, and are usually well conserved compared to the low-scoring ones. Pseudo tRNAs are in heterochromatin/repressed state with anomalous exceptions in cancer cells. We motivate that Epigenetic-Phishing hacks the translation apparatus through the chromatin states governed by the histone marks of tRNA and AARS genes, and speculate on their therapeutic implications in cancer and on stem cells.
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Affiliation(s)
- Sanga Mitra
- a Computational Biology Group , Indian Association for the Cultivation of Science , Jadavpur , Kolkata 700032 , India
| | - Arpa Samadder
- b Computational & Systems Biology, Cancer Genomics, & Molecular Biophysics , University of Massachusetts , Boston , MA 02125 , USA
| | - Pijush Das
- c Structural Biology & Bioinformatics Division , Indian Institute of Chemical Biology , Kolkata 700032 , India
| | - Smarajit Das
- d Department of Genetics , University of Georgia , Athens , GA 30602 , USA
| | - Medhanjali Dasgupta
- e Department of Biochemistry , University of Nebraska-Lincoln , Lincoln , NE 68588 , USA
| | - Jayprokas Chakrabarti
- a Computational Biology Group , Indian Association for the Cultivation of Science , Jadavpur , Kolkata 700032 , India.,f Gyanxet , BF 286 Salt Lake, Kolkata 700064 , India
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12
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Plochowietz A, Farrell I, Smilansky Z, Cooperman BS, Kapanidis AN. In vivo single-RNA tracking shows that most tRNA diffuses freely in live bacteria. Nucleic Acids Res 2016; 45:926-937. [PMID: 27625389 PMCID: PMC5314786 DOI: 10.1093/nar/gkw787] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 07/29/2016] [Accepted: 08/20/2016] [Indexed: 11/21/2022] Open
Abstract
Transfer RNA (tRNA) links messenger RNA nucleotide sequence with amino acid sequence during protein synthesis. Despite the importance of tRNA for translation, its subcellular distribution and diffusion properties in live cells are poorly understood. Here, we provide the first direct report on tRNA diffusion localization in live bacteria. We internalized tRNA labeled with organic fluorophores into live bacteria, applied single-molecule fluorescence imaging with single-particle tracking and localized and tracked single tRNA molecules over seconds. We observed two diffusive species: fast (with a diffusion coefficient of ∼8 μm2/s, consistent with free tRNA) and slow (consistent with tRNA bound to larger complexes). Our data indicate that a large fraction of internalized fluorescent tRNA (>70%) appears to diffuse freely in the bacterial cell. We also obtained the subcellular distribution of fast and slow diffusing tRNA molecules in multiple cells by normalizing for cell morphology. While fast diffusing tRNA is not excluded from the bacterial nucleoid, slow diffusing tRNA is localized to the cell periphery (showing a 30% enrichment versus a uniform distribution), similar to non-uniform localizations previously observed for mRNA and ribosomes.
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Affiliation(s)
- Anne Plochowietz
- Biological Physics Research Group, Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, OX1 3PU, Oxford, UK
| | - Ian Farrell
- Anima Inc, 75 Claremont Road, Suite 102, Bernardsville, NJ 07924-2270, USA.,Department of Chemistry, University of Pennsylvania, 231 S. 34 Street, Philadelphia, PA 19104-6323, USA
| | - Zeev Smilansky
- Anima Inc, 75 Claremont Road, Suite 102, Bernardsville, NJ 07924-2270, USA
| | - Barry S Cooperman
- Department of Chemistry, University of Pennsylvania, 231 S. 34 Street, Philadelphia, PA 19104-6323, USA
| | - Achillefs N Kapanidis
- Biological Physics Research Group, Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, OX1 3PU, Oxford, UK
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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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14
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Chang CY, Chang CP, Chakraborty S, Wang SW, Tseng YK, Wang CC. Modulating the Structure and Function of an Aminoacyl-tRNA Synthetase Cofactor by Biotinylation. J Biol Chem 2016; 291:17102-11. [PMID: 27330079 DOI: 10.1074/jbc.m116.734343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Indexed: 12/20/2022] Open
Abstract
Arc1p is a yeast-specific tRNA-binding protein that forms a ternary complex with glutamyl-tRNA synthetase (GluRSc) and methionyl-tRNA synthetase (MetRS) in the cytoplasm to regulate their catalytic activities and subcellular distributions. Despite Arc1p not being involved in any known biotin-dependent reaction, it is a natural target of biotin modification. Results presented herein show that biotin modification had no obvious effect on the growth-supporting activity, subcellular distribution, tRNA binding, or interactions of Arc1p with GluRSc and MetRS. Nevertheless, biotinylation of Arc1p was temperature dependent; raising the growth temperature from 30 to 37 °C drastically reduced its biotinylation level. As a result, Arc1p purified from a yeast culture that had been grown overnight at 37 °C was essentially biotin free. Non-biotinylated Arc1p was more heat stable, more flexible in structure, and more effective than its biotinylated counterpart in promoting glutamylation activity of the otherwise inactive GluRSc at 37 °C in vitro Our study suggests that the structure and function of Arc1p can be modulated via biotinylation in response to temperature changes.
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Affiliation(s)
| | | | - Shruti Chakraborty
- the Department of Biotechnology, University of Calcutta, Kolkata 700019, India, and
| | - Shao-Win Wang
- the Division of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan Town, Miaoli 35053, Taiwan
| | - Yi-Kuan Tseng
- the Graduate Institute of Statistics, National Central University, Jungli District, Taoyuan 32001, Taiwan
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15
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Santamaría-Gómez J, Ochoa de Alda JAG, Olmedo-Verd E, Bru-Martínez R, Luque I. Sub-Cellular Localization and Complex Formation by Aminoacyl-tRNA Synthetases in Cyanobacteria: Evidence for Interaction of Membrane-Anchored ValRS with ATP Synthase. Front Microbiol 2016; 7:857. [PMID: 27375579 PMCID: PMC4893482 DOI: 10.3389/fmicb.2016.00857] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/23/2016] [Indexed: 01/09/2023] Open
Abstract
tRNAs are charged with cognate amino acids by aminoacyl-tRNA synthetases (aaRSs) and subsequently delivered to the ribosome to be used as substrates for gene translation. Whether aminoacyl-tRNAs are channeled to the ribosome by transit within translational complexes that avoid their diffusion in the cytoplasm is a matter of intense investigation in organisms of the three domains of life. In the cyanobacterium Anabaena sp. PCC 7120, the valyl-tRNA synthetase (ValRS) is anchored to thylakoid membranes by means of the CAAD domain. We have investigated whether in this organism ValRS could act as a hub for the nucleation of a translational complex by attracting other aaRSs to the membranes. Out of the 20 aaRSs, only ValRS was found to localize in thylakoid membranes whereas the other enzymes occupied the soluble portion of the cytoplasm. To investigate the basis for this asymmetric distribution of aaRSs, a global search for proteins interacting with the 20 aaRSs was conducted. The interaction between ValRS and the FoF1 ATP synthase complex here reported is of utmost interest and suggests a functional link between elements of the gene translation and energy production machineries.
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Affiliation(s)
- Javier Santamaría-Gómez
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas and Universidad de SevillaSeville, Spain
| | | | - Elvira Olmedo-Verd
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas and Universidad de SevillaSeville, Spain
| | - Roque Bru-Martínez
- Department of Agrochemistry and Biochemistry, Faculty of Science, University of AlicanteAlicante, Spain
| | - Ignacio Luque
- Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas and Universidad de SevillaSeville, Spain
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16
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Skorupa M, Gołębiewski M, Domagalski K, Kurnik K, Abu Nahia K, Złoch M, Tretyn A, Tyburski J. Transcriptomic profiling of the salt stress response in excised leaves of the halophyte Beta vulgaris ssp. maritima. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2016; 243:56-70. [PMID: 26795151 DOI: 10.1016/j.plantsci.2015.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 11/20/2015] [Accepted: 11/21/2015] [Indexed: 05/21/2023]
Abstract
Beta vulgaris ssp. maritima is a halophytic relative of cultivated beets. In the present work a transcriptome response to acute salt stress imposed to excised leaves of sea beet was investigated. Salt treatments consisted of adding NaCl directly to the transpiration stream by immersing the petioles of excised leaves into the salt solutions. Sequencing libraries were generated from leaves subjected to either moderate or strong salt stress. Control libraries were constructed from untreated leaves. Sequencing was performed using the Illumina MiSeq platform. We obtained 32970 unigenes by assembling the pooled reads from all the libraries with Trinity software. Screening the nr database returned 18,362 sequences with functional annotation. Using the reference transcriptome we identified 1,246 genes that were differentially expressed after 48 h of NaCl stress. Genes related to several cellular functions such as membrane transport, osmoprotection, molecular chaperoning, redox metabolism or protein synthesis were differentially expressed in response to salt stress. The response of sea beet leaves to salt treatments was marked out by transcriptomic up-regulation of genes related to photosynthetic carbon fixation, ribosome biogenesis, cell wall-building and cell wall expansion. Furthermore, several novel and undescribed transcripts were responsive to salinity in leaves of sea beet.
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Affiliation(s)
- Monika Skorupa
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland
| | - Marcin Gołębiewski
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Toruń, Poland
| | - Krzysztof Domagalski
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Toruń, Poland
| | - Katarzyna Kurnik
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland
| | - Karim Abu Nahia
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland
| | - Michał Złoch
- Department of Microbiology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland
| | - Andrzej Tretyn
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Toruń, Poland
| | - Jarosław Tyburski
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Lwowska 1, 87-100 Toruń, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, Wileńska 4, 87-100 Toruń, Poland.
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17
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Ferguson A, Wang L, Altman RB, Terry DS, Juette MF, Burnett BJ, Alejo JL, Dass RA, Parks MM, Vincent CT, Blanchard SC. Functional Dynamics within the Human Ribosome Regulate the Rate of Active Protein Synthesis. Mol Cell 2015; 60:475-86. [PMID: 26593721 PMCID: PMC4660248 DOI: 10.1016/j.molcel.2015.09.013] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 07/24/2015] [Accepted: 09/16/2015] [Indexed: 01/09/2023]
Abstract
The regulation of protein synthesis contributes to gene expression in both normal physiology and disease, yet kinetic investigations of the human translation mechanism are currently lacking. Using single-molecule fluorescence imaging methods, we have quantified the nature and timing of structural processes in human ribosomes during single-turnover and processive translation reactions. These measurements reveal that functional complexes exhibit dynamic behaviors and thermodynamic stabilities distinct from those observed for bacterial systems. Structurally defined sub-states of pre- and post-translocation complexes were sensitive to specific inhibitors of the eukaryotic ribosome, demonstrating the utility of this platform to probe drug mechanism. The application of three-color single-molecule fluorescence resonance energy transfer (smFRET) methods further revealed a long-distance allosteric coupling between distal tRNA binding sites within ribosomes bearing three tRNAs, which contributed to the rate of processive translation.
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Affiliation(s)
- Angelica Ferguson
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA; Tri-Institutional Training Program in Chemical Biology, Weill Cornell Medical College, Rockefeller University, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Leyi Wang
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Roger B Altman
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Daniel S Terry
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Manuel F Juette
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Benjamin J Burnett
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Jose L Alejo
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Randall A Dass
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - Matthew M Parks
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA
| | - C Theresa Vincent
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA; Department of Pharmacology and Physiology, Karolinska Institute, 171 77 Stockholm, Sweden
| | - Scott C Blanchard
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA; Tri-Institutional Training Program in Chemical Biology, Weill Cornell Medical College, Rockefeller University, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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18
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Aminoacyl-tRNA synthetase complexes in evolution. Int J Mol Sci 2015; 16:6571-94. [PMID: 25807264 PMCID: PMC4394549 DOI: 10.3390/ijms16036571] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/17/2015] [Accepted: 03/11/2015] [Indexed: 11/23/2022] Open
Abstract
Aminoacyl-tRNA synthetases are essential enzymes for interpreting the genetic code. They are responsible for the proper pairing of codons on mRNA with amino acids. In addition to this canonical, translational function, they are also involved in the control of many cellular pathways essential for the maintenance of cellular homeostasis. Association of several of these enzymes within supramolecular assemblies is a key feature of organization of the translation apparatus in eukaryotes. It could be a means to control their oscillation between translational functions, when associated within a multi-aminoacyl-tRNA synthetase complex (MARS), and nontranslational functions, after dissociation from the MARS and association with other partners. In this review, we summarize the composition of the different MARS described from archaea to mammals, the mode of assembly of these complexes, and their roles in maintenance of cellular homeostasis.
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19
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Tarrant D, von der Haar T. Synonymous codons, ribosome speed, and eukaryotic gene expression regulation. Cell Mol Life Sci 2014; 71:4195-206. [PMID: 25038778 PMCID: PMC11113527 DOI: 10.1007/s00018-014-1684-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/26/2014] [Accepted: 07/14/2014] [Indexed: 12/27/2022]
Abstract
Quantitative control of gene expression occurs at multiple levels, including the level of translation. Within the overall process of translation, most identified regulatory processes impinge on the initiation phase. However, recent studies have revealed that the elongation phase can also regulate translation if elongation and initiation occur with specific, not mutually compatible rate parameters. Translation elongation then limits the overall amount of protein that can be made from an mRNA. Several recently discovered control mechanisms of biological pathways are based on such elongation control. Here, we review the molecular mechanisms that determine ribosome speed in eukaryotic organisms, and discuss under which conditions ribosome speed can become the controlling parameter of gene expression levels.
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Affiliation(s)
- Daniel Tarrant
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, CT2 7NJ UK
| | - Tobias von der Haar
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, CT2 7NJ UK
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20
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Hadd A, Perona JJ. Coevolution of specificity determinants in eukaryotic glutamyl- and glutaminyl-tRNA synthetases. J Mol Biol 2014; 426:3619-33. [PMID: 25149203 DOI: 10.1016/j.jmb.2014.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/10/2014] [Accepted: 08/07/2014] [Indexed: 11/30/2022]
Abstract
The glutaminyl-tRNA synthetase (GlnRS) enzyme, which pairs glutamine with tRNA(Gln) for protein synthesis, evolved by gene duplication in early eukaryotes from a nondiscriminating glutamyl-tRNA synthetase (GluRS) that aminoacylates both tRNA(Gln) and tRNA(Glu) with glutamate. This ancient GluRS also separately differentiated to exclude tRNA(Gln) as a substrate, and the resulting discriminating GluRS and GlnRS further acquired additional protein domains assisting function in cis (the GlnRS N-terminal Yqey domain) or in trans (the Arc1p protein associating with GluRS). These added domains are absent in contemporary bacterial GlnRS and GluRS. Here, using Saccharomyces cerevisiae enzymes as models, we find that the eukaryote-specific protein domains substantially influence amino acid binding, tRNA binding and aminoacylation efficiency, but they play no role in either specific nucleotide readout or discrimination against noncognate tRNA. Eukaryotic tRNA(Gln) and tRNA(Glu) recognition determinants are found in equivalent positions and are mutually exclusive to a significant degree, with key nucleotides located adjacent to portions of the protein structure that differentiated during the evolution of archaeal nondiscriminating GluRS to GlnRS. These findings provide important corroboration for the evolutionary model and suggest that the added eukaryotic domains arose in response to distinctive selective pressures associated with the greater complexity of the eukaryotic translational apparatus. We also find that the affinity of GluRS for glutamate is significantly increased when Arc1p is not associated with the enzyme. This is consistent with the lower concentration of intracellular glutamate and the dissociation of the Arc1p:GluRS complex upon the diauxic shift to respiratory conditions.
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Affiliation(s)
- Andrew Hadd
- Department of Biochemistry and Molecular Biology, Oregon Health and Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA
| | - John J Perona
- Department of Biochemistry and Molecular Biology, Oregon Health and Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR 97239, USA; Department of Chemistry, Portland State University, PO Box 751, Portland, OR 97207, USA.
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21
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Godinic-Mikulcic V, Jaric J, Greber BJ, Franke V, Hodnik V, Anderluh G, Ban N, Weygand-Durasevic I. Archaeal aminoacyl-tRNA synthetases interact with the ribosome to recycle tRNAs. Nucleic Acids Res 2014; 42:5191-201. [PMID: 24569352 PMCID: PMC4005694 DOI: 10.1093/nar/gku164] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRS) are essential enzymes catalyzing the formation of aminoacyl-tRNAs, the immediate precursors for encoded peptides in ribosomal protein synthesis. Previous studies have suggested a link between tRNA aminoacylation and high-molecular-weight cellular complexes such as the cytoskeleton or ribosomes. However, the structural basis of these interactions and potential mechanistic implications are not well understood. To biochemically characterize these interactions we have used a system of two interacting archaeal aaRSs: an atypical methanogenic-type seryl-tRNA synthetase and an archaeal ArgRS. More specifically, we have shown by thermophoresis and surface plasmon resonance that these two aaRSs bind to the large ribosomal subunit with micromolar affinities. We have identified the L7/L12 stalk and the proteins located near the stalk base as the main sites for aaRS binding. Finally, we have performed a bioinformatics analysis of synonymous codons in the Methanothermobacter thermautotrophicus genome that supports a mechanism in which the deacylated tRNAs may be recharged by aaRSs bound to the ribosome and reused at the next occurrence of a codon encoding the same amino acid. These results suggest a mechanism of tRNA recycling in which aaRSs associate with the L7/L12 stalk region to recapture the tRNAs released from the preceding ribosome in polysomes.
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Affiliation(s)
- Vlatka Godinic-Mikulcic
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102A, HR-10000 Zagreb, Croatia, Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zurich, Switzerland, Department of Molecular Biology, Faculty of Science, University of Zagreb, Horvatovac 102A, HR-10000 Zagreb, Croatia, Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, 1000 Ljubljana, Slovenia and Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
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22
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Dias J, Renault L, Pérez J, Mirande M. Small-angle X-ray solution scattering study of the multi-aminoacyl-tRNA synthetase complex reveals an elongated and multi-armed particle. J Biol Chem 2013; 288:23979-89. [PMID: 23836901 PMCID: PMC3745343 DOI: 10.1074/jbc.m113.489922] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 07/01/2013] [Indexed: 02/01/2023] Open
Abstract
In animal cells, nine aminoacyl-tRNA synthetases are associated with the three auxiliary proteins p18, p38, and p43 to form a stable and conserved large multi-aminoacyl-tRNA synthetase complex (MARS), whose molecular mass has been proposed to be between 1.0 and 1.5 MDa. The complex acts as a molecular hub for coordinating protein synthesis and diverse regulatory signal pathways. Electron microscopy studies defined its low resolution molecular envelope as an overall rather compact, asymmetric triangular shape. Here, we have analyzed the composition and homogeneity of the native mammalian MARS isolated from rabbit liver and characterized its overall internal structure, size, and shape at low resolution by hydrodynamic methods and small-angle x-ray scattering in solution. Our data reveal that the MARS exhibits a much more elongated and multi-armed shape than expected from previous reports. The hydrodynamic and structural features of the MARS are large compared with other supramolecular assemblies involved in translation, including ribosome. The large dimensions and non-compact structural organization of MARS favor a large protein surface accessibility for all its components. This may be essential to allow structural rearrangements between the catalytic and cis-acting tRNA binding domains of the synthetases required for binding the bulky tRNA substrates. This non-compact architecture may also contribute to the spatiotemporal controlled release of some of its components, which participate in non-canonical functions after dissociation from the complex.
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Affiliation(s)
- José Dias
- From the Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France and
| | - Louis Renault
- From the Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France and
| | - Javier Pérez
- SOLEIL Synchrotron, L'Orme des Merisiers Saint-Aubin, Gif-sur-Yvette, France
| | - Marc Mirande
- From the Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France and
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23
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An insertion peptide in yeast glycyl-tRNA synthetase facilitates both productive docking and catalysis of cognate tRNAs. Mol Cell Biol 2013; 33:3515-23. [PMID: 23816885 DOI: 10.1128/mcb.00122-13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The yeast Saccharomyces cerevisiae possesses two distinct glycyl-tRNA synthetase (GlyRS) genes: GRS1 and GRS2. GRS1 is dually functional, encoding both cytoplasmic and mitochondrial activities, while GRS2 is dysfunctional and not required for growth. The protein products of these two genes, GlyRS1 and GlyRS2, are much alike but are distinguished by an insertion peptide of GlyRS1, which is absent from GlyRS2 and other eukaryotic homologues. We show that deletion or mutation of the insertion peptide modestly impaired the enzyme's catalytic efficiency in vitro (with a 2- to 3-fold increase in Km and a 5- to 8-fold decrease in kcat). Consistently, GRS2 can be conveniently converted to a functional gene via codon optimization, and the insertion peptide is dispensable for protein stability and the rescue activity of GRS1 at 30°C in vivo. A phylogenetic analysis further showed that GRS1 and GRS2 are paralogues that arose from a gene duplication event relatively recently, with GRS1 being the predecessor. These results indicate that GlyRS2 is an active enzyme essentially resembling the insertion peptide-deleted form of GlyRS1. Our study suggests that the insertion peptide represents a novel auxiliary domain, which facilitates both productive docking and catalysis of cognate tRNAs.
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24
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Abstract
The aminoacyl-tRNA synthetases (aaRSs) are essential components of the protein synthesis machinery responsible for defining the genetic code by pairing the correct amino acids to their cognate tRNAs. The aaRSs are an ancient enzyme family believed to have origins that may predate the last common ancestor and as such they provide insights into the evolution and development of the extant genetic code. Although the aaRSs have long been viewed as a highly conserved group of enzymes, findings within the last couple of decades have started to demonstrate how diverse and versatile these enzymes really are. Beyond their central role in translation, aaRSs and their numerous homologs have evolved a wide array of alternative functions both inside and outside translation. Current understanding of the emergence of the aaRSs, and their subsequent evolution into a functionally diverse enzyme family, are discussed in this chapter.
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25
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Pavon-Eternod M, David A, Dittmar K, Berglund P, Pan T, Bennink JR, Yewdell JW. Vaccinia and influenza A viruses select rather than adjust tRNAs to optimize translation. Nucleic Acids Res 2012; 41:1914-21. [PMID: 23254333 PMCID: PMC3561966 DOI: 10.1093/nar/gks986] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Transfer RNAs (tRNAs) are central to protein synthesis and impact translational speed and
fidelity by their abundance. Here we examine the extent to which viruses manipulate tRNA
populations to favor translation of their own genes. We study two very different viruses:
influenza A virus (IAV), a medium-sized (13 kB genome) RNA virus; and vaccinia virus (VV),
a large (200 kB genome) DNA virus. We show that the total cellular tRNA population remains
unchanged following viral infection, whereas the polysome-associated tRNA population
changes dramatically in a virus-specific manner. The changes in polysome-associated tRNA
levels reflect the codon usage of viral genes, suggesting the existence of local tRNA
pools optimized for viral translation.
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Affiliation(s)
- Mariana Pavon-Eternod
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA
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26
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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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27
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Dias J, Octobre G, Kobbi L, Comisso M, Flisiak S, Mirande M. Activation of human mitochondrial lysyl-tRNA synthetase upon maturation of its premitochondrial precursor. Biochemistry 2012; 51:909-16. [PMID: 22235746 DOI: 10.1021/bi201337b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The cytoplasmic and mitochondrial species of human lysyl-tRNA synthetase are encoded by a single gene by means of alternative splicing of the KARS1 gene. The cytosolic enzyme possesses a eukaryote-specific N-terminal polypeptide extension that confers on the native enzyme potent tRNA binding properties required for the vectorial transfer of tRNA from the synthetase to elongation factor EF1A within the eukaryotic translation machinery. The mitochondrial enzyme matures from its precursor upon being targeted to that organelle. To understand how the cytosolic and mitochondrial enzymes are adapted to participate in two distinct translation machineries, of eukaryotic or bacterial origin, we characterized the mitochondrial LysRS species. Here we report that cleavage of the precursor of mitochondrial LysRS leads to a mature enzyme with reduced tRNA binding properties compared to those of the cytoplasmic counterpart. This adaptation mechanism may prevent inhibition of translation through sequestration of lysyl-tRNA on the synthetase in a compartment where the bacterial-like elongation factor EF-Tu could not assist in its dissociation from the synthetase. We also observed that the RxxxKRxxK tRNA-binding motif of mitochondrial LysRS is not functional in the precursor form of that enzyme and becomes operational after cleavage of the mitochondrial targeting sequence. The finding that maturation of the precursor is needed to reveal the potent tRNA binding properties of this enzyme has strong implications for the spatiotemporal regulation of its activities and is consistent with previous studies suggesting that the only LysRS species able to promote packaging of tRNA(Lys) into HIV-1 viral particles is the mature form of the mitochondrial enzyme.
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Affiliation(s)
- José Dias
- Laboratoire d'Enzymologie et Biochimie Structurales, Centre de Recherche de Gif, CNRS, Gif-sur-Yvette, France
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28
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Belostotsky R, Frishberg Y, Entelis N. Human mitochondrial tRNA quality control in health and disease: a channelling mechanism? RNA Biol 2012; 9:33-9. [PMID: 22258151 DOI: 10.4161/rna.9.1.18009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Mutations in human mitochondrial tRNA genes are associated with a number of multisystemic disorders. These single nucleotide substitutions in various domains of tRNA molecules may affect different steps of tRNA biogenesis. Often, the prominent decrease of aminoacylation and/or steady-state levels of affected mitochondrial tRNA have been demonstrated in patients' tissues and in cultured cells. Similar effect has been observed for pathogenic mutations in nuclear genes encoding mitochondrial aminoacyl-tRNA-synthetases, while over-expression of mitochondrial aminoacyl-tRNA synthetases or elongation factor EF-Tu rescued mutated tRNAs from degradation. In this review we summarize experimental data concerning the possible regulatory mechanisms governing mitochondrial tRNA steady-state levels, and propose a hypothesis based on the tRNA channelling principle. According to this hypothesis, interaction of mitochondrial tRNA with proteins ensures not only tRNA synthesis, maturation and function, but also protection from degradation. Mutations perturbing this interaction lead to decreased tRNA stability.
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Affiliation(s)
- Ruth Belostotsky
- Division of Pediatric Nephrology, Shaare Zedek Medical Center; Jerusalem, Israel
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29
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Grant TD, Snell EH, Luft JR, Quartley E, Corretore S, Wolfley JR, Snell ME, Hadd A, Perona JJ, Phizicky EM, Grayhack EJ. Structural conservation of an ancient tRNA sensor in eukaryotic glutaminyl-tRNA synthetase. Nucleic Acids Res 2011; 40:3723-31. [PMID: 22180531 PMCID: PMC3333875 DOI: 10.1093/nar/gkr1223] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
In all organisms, aminoacyl tRNA synthetases covalently attach amino acids to their cognate tRNAs. Many eukaryotic tRNA synthetases have acquired appended domains, whose origin, structure and function are poorly understood. The N-terminal appended domain (NTD) of glutaminyl-tRNA synthetase (GlnRS) is intriguing since GlnRS is primarily a eukaryotic enzyme, whereas in other kingdoms Gln-tRNAGln is primarily synthesized by first forming Glu-tRNAGln, followed by conversion to Gln-tRNAGln by a tRNA-dependent amidotransferase. We report a functional and structural analysis of the NTD of Saccharomyces cerevisiae GlnRS, Gln4. Yeast mutants lacking the NTD exhibit growth defects, and Gln4 lacking the NTD has reduced complementarity for tRNAGln and glutamine. The 187-amino acid Gln4 NTD, crystallized and solved at 2.3 Å resolution, consists of two subdomains, each exhibiting an extraordinary structural resemblance to adjacent tRNA specificity-determining domains in the GatB subunit of the GatCAB amidotransferase, which forms Gln-tRNAGln. These subdomains are connected by an apparent hinge comprised of conserved residues. Mutation of these amino acids produces Gln4 variants with reduced affinity for tRNAGln, consistent with a hinge-closing mechanism proposed for GatB recognition of tRNA. Our results suggest a possible origin and function of the NTD that would link the phylogenetically diverse mechanisms of Gln-tRNAGln synthesis.
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Affiliation(s)
- Thomas D Grant
- Hauptman-Woodward Medical Research Institute, Buffalo, NY 14203, USA
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Olmedo-Verd E, Santamaría-Gómez J, Ochoa de Alda JAG, Ribas de Pouplana L, Luque I. Membrane anchoring of aminoacyl-tRNA synthetases by convergent acquisition of a novel protein domain. J Biol Chem 2011; 286:41057-68. [PMID: 21965654 DOI: 10.1074/jbc.m111.242461] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Four distinct aminoacyl-tRNA synthetases (aaRSs) found in some cyanobacterial species contain a novel protein domain that bears two putative transmembrane helices. This CAAD domain is present in glutamyl-, isoleucyl-, leucyl-, and valyl-tRNA synthetases, the latter of which has probably recruited the domain more than once during evolution. Deleting the CAAD domain from the valyl-tRNA synthetase of Anabaena sp. PCC 7120 did not significantly modify the catalytic properties of this enzyme, suggesting that it does not participate in its canonical tRNA-charging function. Multiple lines of evidence suggest that the function of the CAAD domain is structural, mediating the membrane anchorage of the enzyme, although membrane localization of aaRSs has not previously been described in any living organism. Synthetases containing the CAAD domain were localized in the intracytoplasmic thylakoid membranes of cyanobacteria and were largely absent from the plasma membrane. The CAAD domain was necessary and apparently sufficient for protein targeting to membranes. Moreover, localization of aaRSs in thylakoids was important under nitrogen limiting conditions. In Anabaena, a multicellular filamentous cyanobacterium often used as a model for prokaryotic cell differentiation, valyl-tRNA synthetase underwent subcellular relocation at the cell poles during heterocyst differentiation, a process also dependent on the CAAD domain.
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Affiliation(s)
- Elvira Olmedo-Verd
- Instituto de Bioquímica Vegetal y Fotosíntesis, C.S.I.C. and Universidad de Sevilla, Avda Américo Vespucio 49, E-41092 Seville, Spain
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Vondenhoff GHM, Van Aerschot A. Aminoacyl-tRNA synthetase inhibitors as potential antibiotics. Eur J Med Chem 2011; 46:5227-36. [PMID: 21968372 DOI: 10.1016/j.ejmech.2011.08.049] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 08/12/2011] [Accepted: 08/15/2011] [Indexed: 11/29/2022]
Abstract
Increasing resistance to antibiotics is a major problem worldwide and provides the stimulus for development of new bacterial inhibitors with preferably different modes of action. In search for new leads, several new bacterial targets are being exploited beside the use of traditional screening methods. Hereto, inhibition of bacterial protein synthesis is a long-standing validated target. Aminoacyl-tRNA synthetases (aaRSs) play an indispensable role in protein synthesis and their structures proved quite conserved in prokaryotes and eukaryotes. However, some divergence has occurred allowing the development of selective aaRS inhibitors. Following an outline on the action mechanism of aaRSs, an overview will be given of already existing aaRS inhibitors, which are largely based on mimics of the aminoacyl-adenylates, the natural reaction intermediates. This is followed by a discussion on more recent developments in the field and the bioavailability problem.
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Affiliation(s)
- Gaston H M Vondenhoff
- Rega Institute for Medical Research, Laboratory of Medicinal Chemistry, Katholieke Universiteit Leuven, Minderbroedersstraat 10, BE-3000 Leuven, Belgium
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Rubio MAT, Hopper AK. Transfer RNA travels from the cytoplasm to organelles. WILEY INTERDISCIPLINARY REVIEWS-RNA 2011; 2:802-17. [PMID: 21976284 DOI: 10.1002/wrna.93] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Transfer RNAs (tRNAs) encoded by the nuclear genome are surprisingly dynamic. Although tRNAs function in protein synthesis occurring on cytoplasmic ribosomes, tRNAs can transit from the cytoplasm to the nucleus and then again return to the cytoplasm by a process known as the tRNA retrograde process. Subsets of the cytoplasmic tRNAs are also imported into mitochondria and function in mitochondrial protein synthesis. The numbers of tRNA species that are imported into mitochondria differ among organisms, ranging from just a few to the entire set needed to decode mitochondrially encoded mRNAs. For some tRNAs, import is dependent on the mitochondrial protein import machinery, whereas the majority of tRNA mitochondrial import is independent of this machinery. Although cytoplasmic proteins and proteins located on the mitochondrial surface participating in the tRNA import process have been described for several organisms, the identity of these proteins differ among organisms. Likewise, the tRNA determinants required for mitochondrial import differ among tRNA species and organisms. Here, we present an overview and discuss the current state of knowledge regarding the mechanisms involved in the tRNA retrograde process and continue with an overview of tRNA import into mitochondria. Finally, we highlight areas of future research to understand the function and regulation of movement of tRNAs between the cytoplasm and organelles.
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Affiliation(s)
- Mary Anne T Rubio
- Department of Microbiology and Center for RNA Biology, Ohio State University, Columbus, OH 43210, USA
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Kobbi L, Octobre G, Dias J, Comisso M, Mirande M. Association of Mitochondrial Lysyl-tRNA Synthetase with HIV-1 GagPol Involves Catalytic Domain of the Synthetase and Transframe and Integrase Domains of Pol. J Mol Biol 2011; 410:875-86. [DOI: 10.1016/j.jmb.2011.03.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 02/18/2011] [Accepted: 03/02/2011] [Indexed: 11/16/2022]
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Havrylenko S, Legouis R, Negrutskii B, Mirande M. Caenorhabditis elegans evolves a new architecture for the multi-aminoacyl-tRNA synthetase complex. J Biol Chem 2011; 286:28476-87. [PMID: 21685384 DOI: 10.1074/jbc.m111.254037] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
MARS is an evolutionary conserved supramolecular assembly of aminoacyl-tRNA synthetases found in eukaryotes. This complex was thought to be ubiquitous in the deuterostome and protostome clades of bilaterians because similar complexes were isolated from arthropods and vertebrates. However, several features of the component enzymes suggested that in the nematode Caenorhabditis elegans, a species grouped with arthropods in modern phylogeny, this complex might not exist, or should display a significantly different structural organization. C. elegans was also taken as a model system to study in a multicellular organism amenable to experimental approaches, the reason for existence of these supramolecular entities. Here, using a proteomic approach, we have characterized the components of MARS in C. elegans. We show that this organism evolved a specific structural organization of this complex, which contains several bona fide components of the MARS complexes known so far, but also displays significant variations. These data highlight molecular evolution events that took place after radiation of bilaterians. Remarkably, it shows that expansion of MARS assembly in metazoans is not linear, but is the result of additions but also of subtractions along evolution. We then undertook an experimental approach, using inactivation of the endogenous copy of methionyl-tRNA synthetase by RNAi and expression of transgenic variants, to understand the role in complex assembly and the in vivo functionality, of the eukaryotic-specific domains appended to aminoacyl-tRNA synthetases. We show that rescue of the worms and assembly of transgenic variants into MARS rest on the presence of these appended domains.
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Affiliation(s)
- Svitlana Havrylenko
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 1 Avenue de la Terrasse, 91190 Gif-sur-Yvette, France
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Havrylenko S, Legouis R, Negrutskii B, Mirande M. Methionyl-tRNA synthetase from Caenorhabditis elegans: a specific multidomain organization for convergent functional evolution. Protein Sci 2011; 19:2475-84. [PMID: 20954242 DOI: 10.1002/pro.529] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Methionyl-tRNA synthetase (MetRS) is a multidomain protein that specifically binds tRNAMet and catalyzes the synthesis of methionyl-tRNAMet. The minimal, core enzyme found in Aquifex aeolicus is made of a catalytic domain, which catalyzes the aminoacylation reaction, and an anticodon-binding domain, which promotes tRNA-protein association. In eukaryotes, additional domains are appended in cis or in trans to the core enzyme and increase the stability of the tRNA-protein complexes. Eventually, as observed for MetRS from Homo sapiens, the C-terminal appended domain causes a slow release of aminoacyl-tRNA and establishes a limiting step in the global aminoacylation reaction. Here, we report that MetRS from the nematode Caenorhabditis elegans displays a new type of structural organization. Its very C-terminal appended domain is related to the oligonucleotide binding-fold-based tRNA-binding domain (tRBD) recovered at the C-terminus of MetRS from plant, but, in the nematode enzyme, this domain is separated from the core enzyme by an insertion domain. Gel retardation and tRNA aminoacylation experiments show that MetRS from nematode is functionally related to human MetRS despite the fact that their appended tRBDs have distinct structural folds, and are not orthologs. Thus, functional convergence of human and nematode MetRS is the result of parallel and convergent evolution that might have been triggered by the selective pressure to invent processivity of tRNA handling in translation in higher eukaryotes.
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Affiliation(s)
- Svitlana Havrylenko
- Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 91190 Gif-sur-Yvette, France
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Karanasios E, Simos G. Building arks for tRNA: Structure and function of the Arc1p family of non-catalytic tRNA-binding proteins. FEBS Lett 2010; 584:3842-9. [DOI: 10.1016/j.febslet.2010.08.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Revised: 08/14/2010] [Accepted: 08/16/2010] [Indexed: 11/16/2022]
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