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  1 / 241 MEDLINE  
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[PMID]:28703578
[Au] Autor:Wulff TF; Argüello RJ; Molina Jordàn M; Roura Frigolé H; Hauquier G; Filonava L; Camacho N; Gatti E; Pierre P; Ribas de Pouplana L; Torres AG
[Ad] Endereço:Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology , Parc Científic de Barcelona, C/Baldiri Reixac 10, 08028 Barcelona, Catalonia, Spain.
[Ti] Título:Detection of a Subset of Posttranscriptional Transfer RNA Modifications in Vivo with a Restriction Fragment Length Polymorphism-Based Method.
[So] Source:Biochemistry;56(31):4029-4038, 2017 Aug 08.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transfer RNAs (tRNAs) are among the most heavily modified RNA species. Posttranscriptional tRNA modifications (ptRMs) play fundamental roles in modulating tRNA structure and function and are being increasingly linked to human physiology and disease. Detection of ptRMs is often challenging, expensive, and laborious. Restriction fragment length polymorphism (RFLP) analyses study the patterns of DNA cleavage after restriction enzyme treatment and have been used for the qualitative detection of modified bases on mRNAs. It is known that some ptRMs induce specific and reproducible base "mutations" when tRNAs are reverse transcribed. For example, inosine, which derives from the deamination of adenosine, is detected as a guanosine when an inosine-containing tRNA is reverse transcribed, amplified via polymerase chain reaction (PCR), and sequenced. ptRM-dependent base changes on reverse transcription PCR amplicons generated as a consequence of the reverse transcription reaction might create or abolish endonuclease restriction sites. The suitability of RFLP for the detection and/or quantification of ptRMs has not been studied thus far. Here we show that different ptRMs can be detected at specific sites of different tRNA types by RFLP. For the examples studied, we show that this approach can reliably estimate the modification status of the sample, a feature that can be useful in the study of the regulatory role of tRNA modifications in gene expression.
[Mh] Termos MeSH primário: Adenosina Desaminase/metabolismo
Modelos Biológicos
Polimorfismo de Fragmento de Restrição
Processamento Pós-Transcricional do RNA
RNA de Transferência de Alanina/metabolismo
RNA de Transferência de Treonina/metabolismo
[Mh] Termos MeSH secundário: Adenosina/metabolismo
Adenosina Desaminase/química
Adenosina Desaminase/genética
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados
Pareamento de Bases
Biologia Computacional
Desaminação
Sistemas Especialistas
Células HeLa
Seres Humanos
Concentração de Íons de Hidrogênio
Inosina/metabolismo
Interferência de RNA
RNA Interferente Pequeno/metabolismo
RNA de Transferência de Alanina/antagonistas & inibidores
RNA de Transferência de Treonina/antagonistas & inibidores
RNA de Transferência de Valina/antagonistas & inibidores
RNA de Transferência de Valina/metabolismo
Transcrição Reversa
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE; VALIDATION STUDIES
[Nm] Nome de substância:
0 (RNA, Small Interfering); 0 (RNA, Transfer, Ala); 0 (RNA, Transfer, Thr); 0 (RNA, Transfer, Val); 5A614L51CT (Inosine); EC 3.5.4.4 (ADAT2 protein, human); EC 3.5.4.4 (Adenosine Deaminase); K72T3FS567 (Adenosine)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170818
[Lr] Data última revisão:
170818
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170714
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00324


  2 / 241 MEDLINE  
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[PMID]:28111408
[Au] Autor:Xu Y; Chen X; Huang H; Liu W
[Ad] Endereço:Department of Cardiology, The Third Affiliated Hospital of Guangzhou Medical University.
[Ti] Título:The Mitochondrial tRNA T5655C Mutation May Modulate the Phenotypic Expression of tRNA and tRNA A4401G Mutation in a Han Chinese Family With Essential Hypertension.
[So] Source:Int Heart J;58(1):95-99, 2017 Feb 07.
[Is] ISSN:1349-3299
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Mutations in mitochondrial DNA are associated with the pathogenesis of essential hypertension. We report here the clinical, genetic, and molecular characterization of a three-generation Han Chinese family with essential hypertension. Most strikingly, this family exhibited a high penetrance of essential hypertension. Sequence analysis of the mitochondrial genome showed the presence of a homoplasmic T5655C mutation in tRNA , together with the A4401G mutation in the adjacent region between tRNA and tRNA . Notably, the T5655C mutation was localized at the acceptor arm of tRNA , disrupted the high conserved base-pairing (1A-72T), and may impair the tRNA function. Moreover, the A4401G mutation was reported to decrease the steady-state level of tRNA and tRNA , and consequently caused the mitochondrial dysfunction responsible for hypertension. Taken together, the combination of T5655C and A4401G mutations in mitochondrial tRNA genes may account for the high penetrance and expressivity of hypertension in this Chinese family. Thus, our findings may provide new insight into the pathogenesis of this disorder.
[Mh] Termos MeSH primário: DNA Mitocondrial/química
Hipertensão/genética
RNA de Transferência de Alanina/genética
[Mh] Termos MeSH secundário: Adulto
Idoso de 80 Anos ou mais
Análise Mutacional de DNA
Feminino
Genoma Mitocondrial
Seres Humanos
Masculino
Meia-Idade
Linhagem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Mitochondrial); 0 (RNA, Transfer, Ala)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170327
[Lr] Data última revisão:
170327
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170124
[St] Status:MEDLINE
[do] DOI:10.1536/ihj.16-205


  3 / 241 MEDLINE  
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[PMID]:27626666
[Au] Autor:Kauppila JHK; Baines HL; Bratic A; Simard ML; Freyer C; Mourier A; Stamp C; Filograna R; Larsson NG; Greaves LC; Stewart JB
[Ad] Endereço:Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne 50931, Germany.
[Ti] Título:A Phenotype-Driven Approach to Generate Mouse Models with Pathogenic mtDNA Mutations Causing Mitochondrial Disease.
[So] Source:Cell Rep;16(11):2980-2990, 2016 Sep 13.
[Is] ISSN:2211-1247
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Mutations of mtDNA are an important cause of human disease, but few animal models exist. Because mammalian mitochondria cannot be transfected, the development of mice with pathogenic mtDNA mutations has been challenging, and the main strategy has therefore been to introduce mutations found in cell lines into mouse embryos. Here, we describe a phenotype-driven strategy that is based on detecting clonal expansion of pathogenic mtDNA mutations in colonic crypts of founder mice derived from heterozygous mtDNA mutator mice. As proof of concept, we report the generation of a mouse line transmitting a heteroplasmic pathogenic mutation in the alanine tRNA gene of mtDNA displaying typical characteristics of classic mitochondrial disease. In summary, we describe a straightforward and technically simple strategy based on mouse breeding and histology to generate animal models of mtDNA-mutation disease, which will be of great importance for studies of disease pathophysiology and preclinical treatment trials.
[Mh] Termos MeSH primário: DNA Mitocondrial/genética
Doenças Mitocondriais/genética
Mutação/genética
[Mh] Termos MeSH secundário: Animais
Cruzamento
Cardiomiopatias/genética
Cardiomiopatias/fisiopatologia
Células Clonais
Modelos Animais de Doenças
Feminino
Camundongos Endogâmicos C57BL
Doenças Mitocondriais/fisiopatologia
Fenótipo
Biossíntese de Proteínas
RNA de Transferência de Alanina/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Mitochondrial); 0 (RNA, Transfer, Ala)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160915
[St] Status:MEDLINE


  4 / 241 MEDLINE  
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[PMID]:27430335
[Au] Autor:Rojas-Sánchez S; Figueroa-Angulo E; Moreno-Campos R; Florencio-Martínez LE; Manning-Cela RG; Martínez-Calvillo S
[Ad] Endereço:Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Av. de los Barrios 1, Col. Los Reyes Iztacala, Tlalnepantla, Edo. de México, CP 54090, Mexico.
[Ti] Título:Transcription of Leishmania major U2 small nuclear RNA gene is directed by extragenic sequences located within a tRNA-like and a tRNA-Ala gene.
[So] Source:Parasit Vectors;9(1):401, 2016 Jul 19.
[Is] ISSN:1756-3305
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Leishmania and other trypanosomatid parasites possess atypical mechanisms of gene expression, including the maturation of mRNAs by trans-splicing and the involvement of RNA Polymerase III in transcription of all snRNA molecules. Since snRNAs are essential for trans-splicing, we are interested in the study of the sequences that direct their expression. Here we report the characterization of L. major U2 snRNA promoter region. RESULTS: All species of Leishmania possess a single U2 snRNA gene that contains a divergently-oriented tRNA-Ala gene in the upstream region. Between these two genes we found a tRNA-like sequence that possesses conserved boxes A and B. Primer extension and RT-qPCR analyses with RNA from transiently-transfected cells showed that transcription of L. major U2 snRNA is almost abolished when boxes A and B from the tRNA-like are deleted or mutated. The levels of the U2 snRNA were also highly affected when base substitutions were introduced into box B from the tRNA-Ala gene and the first nucleotides of the U2 snRNA gene itself. We also demonstrate that the tRNA-like is transcribed, generating a main transcript of around 109 bases. As pseudouridines in snRNAs are required for splicing in other organisms, we searched for this modified nucleotide in the L. major U2 snRNA. Our results show the presence of six pseudouridines in the U2 snRNA, including one in the Sm site that has not been reported in other organisms. CONCLUSIONS: Four different regions control the transcription of the U2 snRNA gene in L. major: boxes A and B from the neighbor tRNA-like, box B from the upstream tRNA-Ala gene and the first nucleotides of the U2 snRNA. Thus, the promoter region of L. major U2 snRNA is different from any other promoter reported for snRNAs. Pseudouridines could play important roles in L. major U2 snRNA, since they were found in functionally important regions, including the branch point recognition region and the Sm binding site.
[Mh] Termos MeSH primário: Leishmania major/genética
Regiões Promotoras Genéticas
RNA Nuclear Pequeno/biossíntese
RNA de Transferência de Alanina/genética
Transcrição Genética
[Mh] Termos MeSH secundário: Análise Mutacional de DNA
Pseudouridina/análise
RNA Nuclear Pequeno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Small Nuclear); 0 (RNA, Transfer, Ala); 0 (U2 small nuclear RNA); 1445-07-4 (Pseudouridine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160720
[St] Status:MEDLINE
[do] DOI:10.1186/s13071-016-1682-3


  5 / 241 MEDLINE  
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[PMID]:27161322
[Au] Autor:Jiang P; Wang M; Xue L; Xiao Y; Yu J; Wang H; Yao J; Liu H; Peng Y; Liu H; Li H; Chen Y; Guan MX
[Ad] Endereço:Institute of Genetics, Zhejiang University, and Department of Genetics, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
[Ti] Título:A Hypertension-Associated tRNAAla Mutation Alters tRNA Metabolism and Mitochondrial Function.
[So] Source:Mol Cell Biol;36(14):1920-30, 2016 Jul 15.
[Is] ISSN:1098-5549
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this report, we investigated the pathophysiology of a novel hypertension-associated mitochondrial tRNA(Ala) 5655A → G (m.5655A → G) mutation. The destabilization of a highly conserved base pairing (A1-U72) at the aminoacyl acceptor stem by an m.5655A → G mutation altered the tRNA(Ala) function. An in vitro processing analysis showed that the m.5655A → G mutation reduced the efficiency of tRNA(Ala) precursor 5' end cleavage catalyzed by RNase P. By using cybrids constructed by transferring mitochondria from lymphoblastoid cell lines derived from a Chinese family into mitochondrial DNA (mtDNA)-less (ρ(o)) cells, we showed a 41% reduction in the steady-state level of tRNA(Ala) in mutant cybrids. The mutation caused an improperly aminoacylated tRNA(Ala), as suggested by aberrantly aminoacylated tRNA(Ala) and slower electrophoretic mobility of mutated tRNA. A failure in tRNA(Ala) metabolism contributed to variable reductions in six mtDNA-encoded polypeptides in mutant cells, ranging from 21% to 37.5%, with an average of a 29.1% reduction, compared to levels of the controls. The impaired translation caused reduced activities of mitochondrial respiration chains. Furthermore, marked decreases in the levels of mitochondrial ATP and membrane potential were observed in mutant cells. These caused increases in the production of reactive oxygen species in the mutant cybrids. The data provide evidence for the association of the tRNA(Ala) 5655A → G mutation with hypertension.
[Mh] Termos MeSH primário: Grupo com Ancestrais do Continente Asiático/genética
Hipertensão/genética
Mitocôndrias/fisiologia
Mutação
RNA de Transferência de Alanina/genética
RNA de Transferência/metabolismo
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Linhagem Celular
Feminino
Seres Humanos
Masculino
Meia-Idade
Mitocôndrias/genética
Conformação de Ácido Nucleico
RNA/genética
RNA de Transferência de Alanina/química
Espécies Reativas de Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Transfer, Ala); 0 (RNA, mitochondrial); 0 (Reactive Oxygen Species); 63231-63-0 (RNA); 9014-25-9 (RNA, Transfer)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170517
[Lr] Data última revisão:
170517
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160511
[St] Status:MEDLINE
[do] DOI:10.1128/MCB.00199-16


  6 / 241 MEDLINE  
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[PMID]:27079465
[Au] Autor:Seligmann H
[Ad] Endereço:Unité de Recherche sur les Maladies Infectieuses et Tropicales Émergentes, Faculté de Médecine, URMITE CNRS-IRD 198 UMER 6236, Université de la Méditerranée, Marseille, France. Electronic address: timonuslepidus@gmail.com.
[Ti] Título:Swinger RNA self-hybridization and mitochondrial non-canonical swinger transcription, transcription systematically exchanging nucleotides.
[So] Source:J Theor Biol;399:84-91, 2016 Jun 21.
[Is] ISSN:1095-8541
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Stem-loop hairpins punctuate mitochondrial post-transcriptional processing. Regulation of mitochondrial swinger transcription, transcription producing RNAs matching the mitogenome only assuming systematic exchanges between nucleotides (23 bijective transformations along 9 symmetric exchanges X<>Y, e.g. A<>G, and 14 asymmetric exchanges X>Y>Z>X, e.g. A>G>C>A) remains unknown. Does swinger RNA self-hybridization regulate swinger, as regular, transcription? Groups of 8 swinger transformations share canonical self-hybridization properties within each group, group 0 includes identity (regular) transcription. The human mitogenome has more stem-loop hairpins than randomized sequences for all groups. Group 2 transformations reveal complementarity of the light strand replication origin (OL) loop and a neighboring tRNA gene, detecting the longtime presumed OL/tRNA homology. Non-canonical G=U pairings in hairpins increases with swinger RNA detection. These results confirm biological relevancy of swinger-transformed DNA/RNA, independently of, and in combination with, previously detected swinger DNA/RNA and swinger peptides. Swinger-transformed mitogenomes include unsuspected multilayered information.
[Mh] Termos MeSH primário: Hibridização Genética
Mitocôndrias/genética
Nucleotídeos/genética
RNA/genética
Transcrição Genética
[Mh] Termos MeSH secundário: Pareamento Incorreto de Bases/genética
Sequência de Bases
Replicação do DNA/genética
DNA Mitocondrial/genética
Genoma Mitocondrial
Seres Humanos
Sequências Repetidas Invertidas
Conformação de Ácido Nucleico
RNA/química
RNA de Transferência de Alanina/genética
Estatísticas não Paramétricas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Mitochondrial); 0 (Nucleotides); 0 (RNA, Transfer, Ala); 63231-63-0 (RNA)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170904
[Lr] Data última revisão:
170904
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160416
[St] Status:MEDLINE


  7 / 241 MEDLINE  
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[PMID]:26261323
[Au] Autor:Hebecker S; Krausze J; Hasenkampf T; Schneider J; Groenewold M; Reichelt J; Jahn D; Heinz DW; Moser J
[Ad] Endereço:Institute of Microbiology, Technische Universität Braunschweig, 38106 Braunschweig, Germany;
[Ti] Título:Structures of two bacterial resistance factors mediating tRNA-dependent aminoacylation of phosphatidylglycerol with lysine or alanine.
[So] Source:Proc Natl Acad Sci U S A;112(34):10691-6, 2015 Aug 25.
[Is] ISSN:1091-6490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The cytoplasmic membrane is probably the most important physical barrier between microbes and the surrounding habitat. Aminoacylation of the polar head group of the phospholipid phosphatidylglycerol (PG) catalyzed by Ala-tRNA(Ala)-dependent alanyl-phosphatidylglycerol synthase (A-PGS) or by Lys-tRNA(Lys)-dependent lysyl-phosphatidylglycerol synthase (L-PGS) enables bacteria to cope with cationic peptides that are harmful to the integrity of the cell membrane. Accordingly, these synthases also have been designated as multiple peptide resistance factors (MprF). They consist of a separable C-terminal catalytic domain and an N-terminal transmembrane flippase domain. Here we present the X-ray crystallographic structure of the catalytic domain of A-PGS from the opportunistic human pathogen Pseudomonas aeruginosa. In parallel, the structure of the related lysyl-phosphatidylglycerol-specific L-PGS domain from Bacillus licheniformis in complex with the substrate analog L-lysine amide is presented. Both proteins reveal a continuous tunnel that allows the hydrophobic lipid substrate PG and the polar aminoacyl-tRNA substrate to access the catalytic site from opposite directions. Substrate recognition of A-PGS versus L-PGS was investigated using misacylated tRNA variants. The structural work presented here in combination with biochemical experiments using artificial tRNA or artificial lipid substrates reveals the tRNA acceptor stem, the aminoacyl moiety, and the polar head group of PG as the main determinants for substrate recognition. A mutagenesis approach yielded the complementary amino acid determinants of tRNA interaction. These results have broad implications for the design of L-PGS and A-PGS inhibitors that could render microbial pathogens more susceptible to antimicrobial compounds.
[Mh] Termos MeSH primário: Aminoaciltransferases/química
Bacillus/enzimologia
Proteínas de Bactérias/química
Fosfatidilgliceróis/metabolismo
Pseudomonas aeruginosa/enzimologia
Fatores R
RNA de Transferência de Alanina/metabolismo
RNA de Transferência de Lisina/metabolismo
[Mh] Termos MeSH secundário: Aminoacilação
Aminoaciltransferases/metabolismo
Bacillus/genética
Proteínas de Bactérias/metabolismo
Sequência de Bases
Domínio Catalítico
Cristalografia por Raios X
Interações Hidrofóbicas e Hidrofílicas
Lisina/biossíntese
Modelos Moleculares
Simulação de Acoplamento Molecular
Dados de Sequência Molecular
Mutagênese Sítio-Dirigida
Conformação de Ácido Nucleico
Fosfatidilgliceróis/biossíntese
Conformação Proteica
Pseudomonas aeruginosa/genética
Proteínas Recombinantes de Fusão/química
Relação Estrutura-Atividade
Especificidade por Substrato
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Phosphatidylglycerols); 0 (RNA, Transfer, Ala); 0 (RNA, Transfer, Lys); 0 (Recombinant Fusion Proteins); 42241-11-2 (lysylphosphatidylglycerol); EC 2.3.2.- (Aminoacyltransferases); EC 2.3.2.11 (alanyl-phosphatidylglycerol synthase, Pseudomonas aeruginosa); K3Z4F929H6 (Lysine)
[Em] Mês de entrada:1512
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150812
[St] Status:MEDLINE
[do] DOI:10.1073/pnas.1511167112


  8 / 241 MEDLINE  
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[PMID]:25873012
[Au] Autor:Lehmann D; Schubert K; Joshi PR; Hardy SA; Tuppen HA; Baty K; Blakely EL; Bamberg C; Zierz S; Deschauer M; Taylor RW
[Ad] Endereço:Department of Neurology, University of Halle-Wittenberg, Halle (Saale), Germany.
[Ti] Título:Pathogenic mitochondrial mt-tRNA(Ala) variants are uniquely associated with isolated myopathy.
[So] Source:Eur J Hum Genet;23(12):1735-8, 2015 Dec.
[Is] ISSN:1476-5438
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Pathogenic mitochondrial DNA (mtDNA) point mutations are associated with a wide range of clinical phenotypes, often involving multiple organ systems. We report two patients with isolated myopathy owing to novel mt-tRNA(Ala) variants. Muscle biopsy revealed extensive histopathological findings including cytochrome c oxidase (COX)-deficient fibres. Pyrosequencing confirmed mtDNA heteroplasmy for both mutations (m.5631G>A and m.5610G>A) whilst single-muscle fibre segregation studies (revealing statistically significant higher mutation loads in COX-deficient fibres than in COX-positive fibres), hierarchical mutation segregation within patient tissues and decreased steady-state mt-tRNA(Ala) levels all provide compelling evidence of pathogenicity. Interestingly, both patients showed very high-mutation levels in all tissues, inferring that the threshold for impairment of oxidative phosphorylation, as evidenced by COX deficiency, appears to be extremely high for these mt-tRNA(Ala) variants. Previously described mt-tRNA(Ala) mutations are also associated with a pure myopathic phenotype and demonstrate very high mtDNA heteroplasmy thresholds, inferring at least some genotype:phenotype correlation for mutations within this particular mt-tRNA gene.
[Mh] Termos MeSH primário: DNA Mitocondrial/genética
Doenças Musculares/genética
Mutação
RNA de Transferência de Alanina/genética
[Mh] Termos MeSH secundário: Adulto
Idoso
Sequência de Bases
Complexo IV da Cadeia de Transporte de Elétrons/genética
Feminino
Seres Humanos
Dados de Sequência Molecular
Doenças Musculares/diagnóstico
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Mitochondrial); 0 (RNA, Transfer, Ala); EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150416
[St] Status:MEDLINE
[do] DOI:10.1038/ejhg.2015.73


  9 / 241 MEDLINE  
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[PMID]:25586254
[Au] Autor:Iannazzo L; Laisné G; Fonvielle M; Braud E; Herbeuval JP; Arthur M; Etheve-Quelquejeu M
[Ad] Endereço:Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, Team CBNIT, Université Paris Descartes, CNRS UMR 8601, 75006 Paris (France).
[Ti] Título:Synthesis of 3'-fluoro-tRNA analogues for exploring non-ribosomal peptide synthesis in bacteria.
[So] Source:Chembiochem;16(3):477-86, 2015 Feb 09.
[Is] ISSN:1439-7633
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Aminoacyl-tRNAs (aa-tRNAs) participate in a vast repertoire of metabolic pathways, including the synthesis of the peptidoglycan network in the cell walls of bacterial pathogens. Synthesis of aminoacyl-tRNA analogues is critical for further understanding the mechanisms of these reactions. Here we report the semi-synthesis of 3'-fluoro analogues of Ala-tRNA(Ala) . The presence of fluorine in the 3'-position blocks Ala at the 2'-position by preventing spontaneous migration of the residue between positions 2' and 3'. NMR analyses showed that substitution of the 3'-hydroxy group by fluorine in the ribo configuration favours the S-type conformation of the furanose ring of terminal adenosine A76. In contrast, the N-type conformation is favoured by the presence of fluorine in the xylo configuration. Thus, introduction of fluorine in the ribo and xylo configurations affects the conformation of the furanose ring in reciprocal ways. These compounds should provide insight into substrate recognition by Fem transferases and the Ala-tRNA synthetases.
[Mh] Termos MeSH primário: Bioquímica/métodos
Flúor/química
RNA de Transferência de Alanina/química
[Mh] Termos MeSH secundário: Técnicas de Química Sintética
Espectroscopia de Ressonância Magnética
Estrutura Molecular
Conformação de Ácido Nucleico
RNA Ligase (ATP)/química
RNA de Transferência de Alanina/síntese química
Proteínas Virais/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (RNA, Transfer, Ala); 0 (Viral Proteins); 284SYP0193 (Fluorine); EC 6.5.1.3 (RNA Ligase (ATP)); EC 6.5.1.3 (bacteriophage T4 RNA ligase 2)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:150203
[Lr] Data última revisão:
150203
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150115
[St] Status:MEDLINE
[do] DOI:10.1002/cbic.201402523


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[PMID]:25554787
[Au] Autor:Shen PS; Park J; Qin Y; Li X; Parsawar K; Larson MH; Cox J; Cheng Y; Lambowitz AM; Weissman JS; Brandman O; Frost A
[Ad] Endereço:Department of Biochemistry, University of Utah, UT 84112, USA.
[Ti] Título:Protein synthesis. Rqc2p and 60S ribosomal subunits mediate mRNA-independent elongation of nascent chains.
[So] Source:Science;347(6217):75-8, 2015 Jan 02.
[Is] ISSN:1095-9203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In Eukarya, stalled translation induces 40S dissociation and recruitment of the ribosome quality control complex (RQC) to the 60S subunit, which mediates nascent chain degradation. Here we report cryo-electron microscopy structures revealing that the RQC components Rqc2p (YPL009C/Tae2) and Ltn1p (YMR247C/Rkr1) bind to the 60S subunit at sites exposed after 40S dissociation, placing the Ltn1p RING (Really Interesting New Gene) domain near the exit channel and Rqc2p over the P-site transfer RNA (tRNA). We further demonstrate that Rqc2p recruits alanine- and threonine-charged tRNA to the A site and directs the elongation of nascent chains independently of mRNA or 40S subunits. Our work uncovers an unexpected mechanism of protein synthesis, in which a protein--not an mRNA--determines tRNA recruitment and the tagging of nascent chains with carboxy-terminal Ala and Thr extensions ("CAT tails").
[Mh] Termos MeSH primário: Biossíntese de Peptídeos Independentes de Ácido Nucleico
Subunidades Ribossômicas Maiores de Eucariotos/metabolismo
Proteínas de Saccharomyces cerevisiae/metabolismo
Saccharomyces cerevisiae/metabolismo
Ubiquitina-Proteína Ligases/metabolismo
[Mh] Termos MeSH secundário: Microscopia Crioeletrônica
Conformação de Ácido Nucleico
Conformação Proteica
RNA Mensageiro/metabolismo
RNA de Transferência de Alanina/química
RNA de Transferência de Alanina/metabolismo
RNA de Transferência de Treonina/química
RNA de Transferência de Treonina/metabolismo
Proteínas de Ligação a RNA
Subunidades Ribossômicas Maiores de Eucariotos/química
Subunidades Ribossômicas Maiores de Eucariotos/ultraestrutura
Saccharomyces cerevisiae/genética
Proteínas de Saccharomyces cerevisiae/ultraestrutura
Ubiquitina-Proteína Ligases/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (RNA, Messenger); 0 (RNA, Transfer, Ala); 0 (RNA, Transfer, Thr); 0 (RNA-Binding Proteins); 0 (Saccharomyces cerevisiae Proteins); 0 (Tae2 protein, S cerevisiae); EC 2.3.2.27 (Ltn1 protein, S cerevisiae); EC 2.3.2.27 (Rkr1 protein, S cerevisiae); EC 2.3.2.27 (Ubiquitin-Protein Ligases)
[Em] Mês de entrada:1501
[Cu] Atualização por classe:161125
[Lr] Data última revisão:
161125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150103
[St] Status:MEDLINE
[do] DOI:10.1126/science.1259724



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