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Rosenberg M, Blum R, Kesner B, Aeby E, Garant JM, Szanto A, Lee JT. Motif-driven interactions between RNA and PRC2 are rheostats that regulate transcription elongation. Nat Struct Mol Biol 2021; 28:103-117. [PMID: 33398172 PMCID: PMC8050941 DOI: 10.1038/s41594-020-00535-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 10/20/2020] [Indexed: 01/30/2023]
Abstract
Although Polycomb repressive complex 2 (PRC2) is now recognized as an RNA-binding complex, the full range of binding motifs and why PRC2-RNA complexes often associate with active genes have not been elucidated. Here we identify high-affinity RNA motifs whose mutations weaken PRC2 binding and attenuate its repressive function in mouse embryonic stem cells. Interactions occur at promoter-proximal regions and frequently coincide with pausing of RNA Polymerase II (POL-II). Surprisingly, while PRC2-associated nascent transcripts are highly expressed, ablating PRC2 further upregulates expression via loss of pausing and enhanced transcription elongation. Thus, PRC2-nascent RNA complexes operate as rheostats to fine-tune transcription by regulating transitions between pausing and elongation, explaining why PRC2-RNA complexes frequently occur within active genes. Nascent RNA also targets PRC2 in cis and downregulates neighboring genes. We propose a unifying model in which RNA specifically recruits PRC2 to repress genes through POL-II pausing and, more classically, H3K27-trimethylation.
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Affiliation(s)
- Michael Rosenberg
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Roy Blum
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Barry Kesner
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Eric Aeby
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Jean-Michel Garant
- Canada's Michael Smith Genome Sciences Centre, Vancouver, British Columbia, Canada.,RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Attila Szanto
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Jeannie T Lee
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA. .,Department of Genetics, Harvard Medical School, Boston, MA, USA.
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2
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Aeby E, Lee HG, Lee YW, Kriz A, del Rosario BC, Oh HJ, Boukhali M, Haas W, Lee JT. Decapping enzyme 1A breaks X-chromosome symmetry by controlling Tsix elongation and RNA turnover. Nat Cell Biol 2020; 22:1116-1129. [PMID: 32807903 DOI: 10.1038/s41556-020-0558-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/09/2020] [Indexed: 12/27/2022]
Abstract
How allelic asymmetry is generated remains a major unsolved problem in epigenetics. Here we model the problem using X-chromosome inactivation by developing "BioRBP", an enzymatic RNA-proteomic method that enables probing of low-abundance interactions and an allelic RNA-depletion and -tagging system. We identify messenger RNA-decapping enzyme 1A (DCP1A) as a key regulator of Tsix, a noncoding RNA implicated in allelic choice through X-chromosome pairing. DCP1A controls Tsix half-life and transcription elongation. Depleting DCP1A causes accumulation of X-X pairs and perturbs the transition to monoallelic Tsix expression required for Xist upregulation. While ablating DCP1A causes hyperpairing, forcing Tsix degradation resolves pairing and enables Xist upregulation. We link pairing to allelic partitioning of CCCTC-binding factor (CTCF) and show that tethering DCP1A to one Tsix allele is sufficient to drive monoallelic Xist expression. Thus, DCP1A flips a bistable switch for the mutually exclusive determination of active and inactive Xs.
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Aeby E, Ahmed W, Redon S, Simanis V, Lingner J. Peroxiredoxin 1 Protects Telomeres from Oxidative Damage and Preserves Telomeric DNA for Extension by Telomerase. Cell Rep 2017; 17:3107-3114. [PMID: 28009281 DOI: 10.1016/j.celrep.2016.11.071] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/04/2016] [Accepted: 11/22/2016] [Indexed: 01/19/2023] Open
Abstract
Oxidative damage of telomeres can promote cancer, cardiac failure, and muscular dystrophy. Specific mechanisms protecting telomeres from oxidative damage have not been described. We analyzed telomeric chromatin composition during the cell cycle and show that the antioxidant enzyme peroxiredoxin 1 (PRDX1) is enriched at telomeres during S phase. Deletion of the PRDX1 gene leads to damage of telomeric DNA upon oxidative stress, revealing a protective function of PRDX1 against oxidative damage at telomeres. We also show that the oxidized nucleotide 8-oxo-2'deoxyguanosine-5'-triphosphate (8oxodGTP) causes premature chain termination when incorporated by telomerase and that some DNA substrates terminating in 8oxoG prevent extension by telomerase. Thus, PRDX1 safeguards telomeres from oxygen radicals to counteract telomere damage and preserve telomeric DNA for elongation by telomerase.
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Affiliation(s)
- Eric Aeby
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Wareed Ahmed
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Sophie Redon
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Viesturs Simanis
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Joachim Lingner
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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Benarroch-Popivker D, Pisano S, Mendez-Bermudez A, Lototska L, Kaur P, Bauwens S, Djerbi N, Latrick CM, Fraisier V, Pei B, Gay A, Jaune E, Foucher K, Cherfils-Vicini J, Aeby E, Miron S, Londoño-Vallejo A, Ye J, Le Du MH, Wang H, Gilson E, Giraud-Panis MJ. TRF2-Mediated Control of Telomere DNA Topology as a Mechanism for Chromosome-End Protection. Mol Cell 2016; 61:274-86. [PMID: 26774283 DOI: 10.1016/j.molcel.2015.12.009] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/14/2015] [Accepted: 11/30/2015] [Indexed: 02/07/2023]
Abstract
The shelterin proteins protect telomeres against activation of the DNA damage checkpoints and recombinational repair. We show here that a dimer of the shelterin subunit TRF2 wraps ∼ 90 bp of DNA through several lysine and arginine residues localized around its homodimerization domain. The expression of a wrapping-deficient TRF2 mutant, named Top-less, alters telomeric DNA topology, decreases the number of terminal loops (t-loops), and triggers the ATM checkpoint, while still protecting telomeres against non-homologous end joining (NHEJ). In Top-less cells, the protection against NHEJ is alleviated if the expression of the TRF2-interacting protein RAP1 is reduced. We conclude that a distinctive topological state of telomeric DNA, controlled by the TRF2-dependent DNA wrapping and linked to t-loop formation, inhibits both ATM activation and NHEJ. The presence of RAP1 at telomeres appears as a backup mechanism to prevent NHEJ when topology-mediated telomere protection is impaired.
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Affiliation(s)
- Delphine Benarroch-Popivker
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Sabrina Pisano
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Aaron Mendez-Bermudez
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France; International Laboratory in Hematology and Cancer, Shanghai Jiao Tong University School of Medicine/Ruijin Hospital/CNRS/INSERM/Nice University, Pôle Sino-Français de Recherche en Sciences du Vivant et Génomique, Shanghai Ruijin Hospital, Huangpu, Shanghai 200025, P.R. China
| | - Liudmyla Lototska
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Parminder Kaur
- Physics Department, North Carolina State University at Raleigh, Raleigh, NC 27695, USA
| | - Serge Bauwens
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Nadir Djerbi
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Chrysa M Latrick
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Vincent Fraisier
- Cell and Tissue Imaging Platform (PICT-IBiSA), Nikon Imaging Centre, UMR 144 CNRS Institut Curie, 75248 Paris Cedex 05, France
| | - Bei Pei
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Alexandre Gay
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Emilie Jaune
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Kevin Foucher
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Julien Cherfils-Vicini
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France
| | - Eric Aeby
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Simona Miron
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 144, CEA Saclay, Gif-sur-Yvette F-91191, France
| | | | - Jing Ye
- International Laboratory in Hematology and Cancer, Shanghai Jiao Tong University School of Medicine/Ruijin Hospital/CNRS/INSERM/Nice University, Pôle Sino-Français de Recherche en Sciences du Vivant et Génomique, Shanghai Ruijin Hospital, Huangpu, Shanghai 200025, P.R. China
| | - Marie-Hélène Le Du
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Bâtiment 144, CEA Saclay, Gif-sur-Yvette F-91191, France
| | - Hong Wang
- Physics Department, North Carolina State University at Raleigh, Raleigh, NC 27695, USA
| | - Eric Gilson
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France; International Laboratory in Hematology and Cancer, Shanghai Jiao Tong University School of Medicine/Ruijin Hospital/CNRS/INSERM/Nice University, Pôle Sino-Français de Recherche en Sciences du Vivant et Génomique, Shanghai Ruijin Hospital, Huangpu, Shanghai 200025, P.R. China; Department of Genetics, CHU Nice, Nice 06202, France.
| | - Marie-Josèphe Giraud-Panis
- Institute for Research on Cancer and Aging, Nice (IRCAN), Faculty of Medicine, CNRS UMR7284, INSERM U1081, University of Nice Sophia Antipolis, Nice, France.
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Grolimund L, Aeby E, Hamelin R, Armand F, Chiappe D, Moniatte M, Lingner J. A quantitative telomeric chromatin isolation protocol identifies different telomeric states. Nat Commun 2013; 4:2848. [DOI: 10.1038/ncomms3848] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 10/31/2013] [Indexed: 01/08/2023] Open
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Aeby E, Ullu E, Yepiskoposyan H, Schimanski B, Roditi I, Mühlemann O, Schneider A. tRNASec is transcribed by RNA polymerase II in Trypanosoma brucei but not in humans. Nucleic Acids Res 2010; 38:5833-43. [PMID: 20444878 PMCID: PMC2943599 DOI: 10.1093/nar/gkq345] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Nuclear-encoded tRNAs are universally transcribed by RNA polymerase III (Pol-III) and contain intragenic promoters. Transcription of vertebrate tRNASec however requires extragenic promoters similar to Pol-III transcribed U6 snRNA. Here, we present a comparative analysis of tRNASec transcription in humans and the parasitic protozoa Trypanosoma brucei, two evolutionary highly diverged eukaryotes. RNAi-mediated ablation of Pol-II and Pol-III as well as oligo-dT induced transcription termination show that the human tRNASec is a Pol-III transcript. In T. brucei protein-coding genes are polycistronically transcribed by Pol-II and processed by trans-splicing and polyadenylation. tRNA genes are generally clustered in between polycistrons. However, the trypanosomal tRNASec genes are embedded within a polycistron. Their transcription is sensitive to α-amanitin and RNAi-mediated ablation of Pol-II, but not of Pol-III. Ectopic expression of the tRNASec outside but not inside a polycistron requires an added external promoter. These experiments demonstrate that trypanosomal tRNASec, in contrast to its human counterpart, is transcribed by Pol-II. Synteny analysis shows that in trypanosomatids the tRNASec gene can be found in two different polycistrons, suggesting that it has evolved twice independently. Moreover, intron-encoded tRNAs are present in a number of eukaryotic genomes indicating that Pol-II transcription of tRNAs may not be restricted to trypanosomatids.
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Affiliation(s)
- Eric Aeby
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
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Pino P, Aeby E, Foth BJ, Sheiner L, Soldati T, Schneider A, Soldati-Favre D. Mitochondrial translation in absence of local tRNA aminoacylation and methionyl tRNA Met formylation in Apicomplexa. Mol Microbiol 2010; 76:706-18. [PMID: 20374492 DOI: 10.1111/j.1365-2958.2010.07128.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Apicomplexans possess three translationally active compartments: the cytosol, a single tubular mitochondrion, and a vestigial plastid organelle called apicoplast. Mitochondrion and apicoplast are of bacterial evolutionary origin and therefore depend on a bacterial-like translation machinery. The minimal mitochondrial genome contains only three ORFs, and in Toxoplasma gondii the absence of mitochondrial tRNA genes is compensated for by the import of cytosolic eukaryotic tRNAs. Although all compartments require a complete set of charged tRNAs, the apicomplexan nuclear genomes do not hold sufficient aminoacyl-tRNA synthetase (aaRSs) genes to be targeted individually to each compartment. This study reveals that aaRSs are either cytosolic, apicoplastic or shared between the two compartments by dual targeting but are absent from the mitochondrion. Consequently, tRNAs are very likely imported in their aminoacylated form. Furthermore, the unexpected absence of tRNA(Met) formyltransferase and peptide deformylase implies that the requirement for a specialized formylmethionyl-tRNA(Met) for translation initiation is bypassed in the mitochondrion of Apicomplexa.
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Affiliation(s)
- Paco Pino
- Department of Microbiology and Molecular Medicine, CMU, University of Geneva, 1 rue Michel-Servet, 1211 Geneva 4, Switzerland
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Aeby E, Seidel V, Schneider A. The selenoproteome is dispensable in bloodstream forms of Trypanosoma brucei. Mol Biochem Parasitol 2009; 168:191-3. [DOI: 10.1016/j.molbiopara.2009.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Revised: 08/24/2009] [Accepted: 08/25/2009] [Indexed: 01/23/2023]
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Geslain R, Aeby E, Guitart T, Jones TE, Castro de Moura M, Charrière F, Schneider A, Ribas de Pouplana L. Trypanosoma seryl-tRNA synthetase is a metazoan-like enzyme with high affinity for tRNASec. J Biol Chem 2009. [DOI: 10.1074/jbc.a607862200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Bouzaidi-Tiali N, Aeby E, Charrière F, Pusnik M, Schneider A. Elongation factor 1a mediates the specificity of mitochondrial tRNA import in T. brucei. EMBO J 2007; 26:4302-12. [PMID: 17853889 PMCID: PMC2034667 DOI: 10.1038/sj.emboj.7601857] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Accepted: 08/22/2007] [Indexed: 11/09/2022] Open
Abstract
Mitochondrial tRNA import is widespread in eukaryotes. Yet, the mechanism that determines its specificity is unknown. Previous in vivo experiments using the tRNAs(Met), tRNA(Ile) and tRNA(Lys) have suggested that the T-stem nucleotide pair 51:63 is the main localization determinant of tRNAs in Trypanosoma brucei. In the cytosol-specific initiator tRNA(Met), this nucleotide pair is identical to the main antideterminant that prevents interaction with cytosolic elongation factor (eEF1a). Here we show that ablation of cytosolic eEF1a, but not of initiation factor 2, inhibits mitochondrial import of newly synthesized tRNAs well before translation or growth is affected. tRNA(Sec) is the only other cytosol-specific tRNA in T. brucei. It has its own elongation factor and does not bind eEF1a. However, a mutant of the tRNA(Sec) expected to bind to eEF1a is imported into mitochondria. This import requires eEF1a and aminoacylation of the tRNA. Thus, for a tRNA to be imported into the mitochondrion of T. brucei, it needs to bind eEF1a, and it is this interaction that mediates the import specificity.
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Affiliation(s)
- Nabile Bouzaidi-Tiali
- Department of Biology/Cell and Developmental Biology, University of Fribourg, Chemin du Musée 10, Fribourg, Switzerland
| | - Eric Aeby
- Department of Biology/Cell and Developmental Biology, University of Fribourg, Chemin du Musée 10, Fribourg, Switzerland
| | - Fabien Charrière
- Department of Biology/Cell and Developmental Biology, University of Fribourg, Chemin du Musée 10, Fribourg, Switzerland
| | - Mascha Pusnik
- Department of Biology/Cell and Developmental Biology, University of Fribourg, Chemin du Musée 10, Fribourg, Switzerland
| | - André Schneider
- Department of Biology/Cell and Developmental Biology, University of Fribourg, Chemin du Musée 10, Fribourg, Switzerland
- Department of Biology, University of Fribourg, Chemin du Musee 10, Fribourg 1700, Switzerland. Tel.: +41 26 300 8877; Fax: +41 26 300 9741; E-mail:
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Geslain R, Aeby E, Guitart T, Jones TE, Castro de Moura M, Charrière F, Schneider A, Ribas de Pouplana L. Trypanosoma seryl-tRNA synthetase is a metazoan-like enzyme with high affinity for tRNASec. J Biol Chem 2006; 281:38217-25. [PMID: 17040903 DOI: 10.1074/jbc.m607862200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Trypanosomatids are important human pathogens that form a basal branch of eukaryotes. Their evolutionary history is still unclear as are many aspects of their molecular biology. Here we characterize essential components required for the incorporation of serine and selenocysteine into the proteome of Trypanosoma. First, the biological function of a putative Trypanosoma seryl-tRNA synthetase was characterized in vivo. Secondly, the molecular recognition by Trypanosoma seryl-tRNA synthetase of its cognate tRNAs was dissected in vitro. The cellular distribution of tRNA(Sec) was studied, and the catalytic constants of its aminoacylation were determined. These were found to be markedly different from those reported in other organisms, indicating that this reaction is particularly efficient in trypanosomatids. Our functional data were analyzed in the context of a new phylogenetic analysis of eukaryotic seryl-tRNA synthetases that includes Trypanosoma and Leishmania sequences. Our results show that trypanosomatid seryl-tRNA synthetases are functionally and evolutionarily more closely related to their metazoan homologous enzymes than to other eukaryotic enzymes. This conclusion is supported by sequence synapomorphies that clearly connect metazoan and trypanosomatid seryl-tRNA synthetases.
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Affiliation(s)
- Renaud Geslain
- Institució Catalana de Recerca i Estudis Avançats (ICREA) and Institute for Research in Biomedicine, Barcelona, Barcelona Science Park, C/Samitier 1-5, Barcelona 08015, Catalonia, Spain
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