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[PMID]:27820829
[Au] Autor:Kim YE; Higgs PG
[Ad] Endereço:Origins Institute and Department of Physics and Astronomy McMaster University, Hamilton, Ontario, Canada.
[Ti] Título:Co-operation between Polymerases and Nucleotide Synthetases in the RNA World.
[So] Source:PLoS Comput Biol;12(11):e1005161, 2016 Nov.
[Is] ISSN:1553-7358
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:It is believed that life passed through an RNA World stage in which replication was sustained by catalytic RNAs (ribozymes). The two most obvious types of ribozymes are a polymerase, which uses a neighbouring strand as a template to make a complementary sequence to the template, and a nucleotide synthetase, which synthesizes monomers for use by the polymerase. When a chemical source of monomers is available, the polymerase can survive on its own. When the chemical supply of monomers is too low, nucleotide production by the synthetase is essential and the two ribozymes can only survive when they are together. Here we consider a computational model to investigate conditions under which coexistence and cooperation of these two types of ribozymes is possible. The model considers six types of strands: the two functional sequences, the complementary strands to these sequences (which are required as templates), and non-functional mutants of the two sequences (which act as parasites). Strands are distributed on a two-dimensional lattice. Polymerases replicate strands on neighbouring sites and synthetases produce monomers that diffuse in the local neighbourhood. We show that coexistence of unlinked polymerases and synthetases is possible in this spatial model under conditions in which neither sequence could survive alone; hence, there is a selective force for increasing complexity. Coexistence is dependent on the relative lengths of the two functional strands, the strand diffusion rate, the monomer diffusion rate, and the rate of deleterious mutations. The sensitivity of this two-ribozyme system suggests that evolution of a system of many types of ribozymes would be difficult in a purely spatial model with unlinked genes. We therefore speculate that linkage of genes onto mini-chromosomes and encapsulation of strands in protocells would have been important fairly early in the history of life as a means of enabling more complex systems to evolve.
[Mh] Termos MeSH primário: RNA Polimerases Dirigidas por DNA/genética
Evolução Molecular
Modelos Químicos
Modelos Genéticos
Polinucleotídeo Ligases/genética
RNA Catalítico/genética
[Mh] Termos MeSH secundário: RNA Polimerases Dirigidas por DNA/química
Ativação Enzimática
Modelos Estatísticos
Polinucleotídeo Ligases/química
RNA Catalítico/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Catalytic); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170530
[Lr] Data última revisão:
170530
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161108
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pcbi.1005161


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[PMID]:27706059
[Au] Autor:Olea C; Joyce GF
[Ad] Endereço:Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA. colea@scripps.edu.
[Ti] Título:Real-Time Detection of a Self-Replicating RNA Enzyme.
[So] Source:Molecules;21(10), 2016 Sep 30.
[Is] ISSN:1420-3049
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:A system was developed to detect the self-replication of an RNA enzyme in real time. The enzyme is an RNA ligase that undergoes exponential amplification at a constant temperature and can be made to operate in a ligand-dependent manner. The real-time system is based on a fluorimetric readout that directly couples the ligation event to an increase in florescence signal that can be monitored using standard instrumentation. The real-time system can also operate entirely with l-RNA, which is not susceptible to degradation by ribonucleases that are present in biological samples. The system is analogous to real-time PCR, but with the potential to detect small molecules, proteins, and other targets that can be recognized by a suitable aptamer. The ligand-dependent self-replication of RNA has potential applications in molecular diagnostics and biosensing that benefit from the rapid, precise, and real-time detection of various target molecules.
[Mh] Termos MeSH primário: Técnicas de Amplificação de Ácido Nucleico/métodos
Polinucleotídeo Ligases/química
RNA Catalítico/química
RNA/química
RNA/síntese química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Catalytic); 63231-63-0 (RNA); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170930
[Lr] Data última revisão:
170930
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161006
[St] Status:MEDLINE


  3 / 740 MEDLINE  
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[PMID]:26735012
[Au] Autor:Ponce-Salvatierra A; Wawrzyniak-Turek K; Steuerwald U; Höbartner C; Pena V
[Ad] Endereço:Max Planck Research Group Nucleic Acid Chemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
[Ti] Título:Crystal structure of a DNA catalyst.
[So] Source:Nature;529(7585):231-4, 2016 Jan 14.
[Is] ISSN:1476-4687
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Catalysis in biology is restricted to RNA (ribozymes) and protein enzymes, but synthetic biomolecular catalysts can also be made of DNA (deoxyribozymes) or synthetic genetic polymers. In vitro selection from synthetic random DNA libraries identified DNA catalysts for various chemical reactions beyond RNA backbone cleavage. DNA-catalysed reactions include RNA and DNA ligation in various topologies, hydrolytic cleavage and photorepair of DNA, as well as reactions of peptides and small molecules. In spite of comprehensive biochemical studies of DNA catalysts for two decades, fundamental mechanistic understanding of their function is lacking in the absence of three-dimensional models at atomic resolution. Early attempts to solve the crystal structure of an RNA-cleaving deoxyribozyme resulted in a catalytically irrelevant nucleic acid fold. Here we report the crystal structure of the RNA-ligating deoxyribozyme 9DB1 (ref. 14) at 2.8 Å resolution. The structure captures the ligation reaction in the post-catalytic state, revealing a compact folding unit stabilized by numerous tertiary interactions, and an unanticipated organization of the catalytic centre. Structure-guided mutagenesis provided insights into the basis for regioselectivity of the ligation reaction and allowed remarkable manipulation of substrate recognition and reaction rate. Moreover, the structure highlights how the specific properties of deoxyribose are reflected in the backbone conformation of the DNA catalyst, in support of its intricate three-dimensional organization. The structural principles underlying the catalytic ability of DNA elucidate differences and similarities in DNA versus RNA catalysts, which is relevant for comprehending the privileged position of folded RNA in the prebiotic world and in current organisms.
[Mh] Termos MeSH primário: DNA Catalítico/química
Conformação de Ácido Nucleico
[Mh] Termos MeSH secundário: Sequência de Bases
Biocatálise
Domínio Catalítico
Cristalografia por Raios X
DNA Catalítico/síntese química
DNA Catalítico/metabolismo
Desoxirribose/química
Desoxirribose/metabolismo
Cinética
Modelos Moleculares
Dados de Sequência Molecular
Nucleotídeos/química
Nucleotídeos/metabolismo
Polinucleotídeo Ligases/química
Polinucleotídeo Ligases/metabolismo
RNA/química
RNA/metabolismo
Dobramento de RNA
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Catalytic); 0 (Nucleotides); 533-67-5 (Deoxyribose); 63231-63-0 (RNA); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1602
[Cu] Atualização por classe:160602
[Lr] Data última revisão:
160602
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160107
[St] Status:MEDLINE
[do] DOI:10.1038/nature16471


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[PMID]:23384307
[Au] Autor:Ferretti AC; Joyce GF
[Ad] Endereço:Departments of Chemistry and Molecular Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
[Ti] Título:Kinetic properties of an RNA enzyme that undergoes self-sustained exponential amplification.
[So] Source:Biochemistry;52(7):1227-35, 2013 Feb 19.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A special class of biochemical reactions involves a set of enzymes that generate additional copies of themselves and transfer heritable information from parent to progeny molecules, thus providing the basis for genetics and Darwinian evolution. Such a process has been realized with a pair of self-replicating RNA enzymes that undergo exponential amplification at a constant temperature. Exponential growth requires that the rate of production of new enzymes be directly proportional to the existing concentration of enzymes, which is the case for this system and provides a doubling time of ~20 min. However, the catalytic rate of the underlying enzymes is ~100-fold faster than the observed rate of replication. As in biological replication, other aspects of the system limit the generation time, chiefly the propensity of the substrate molecules to form nonproductive complexes that limit their availability for replication. An analysis of this and other kinetic properties of the self-replicating RNA enzymes reveals how exponential amplification is achieved and how the rate of amplification might be increased.
[Mh] Termos MeSH primário: Modelos Químicos
Polinucleotídeo Ligases/química
Polinucleotídeo Ligases/metabolismo
[Mh] Termos MeSH secundário: Pareamento de Bases
Sequência de Bases
Cinética
Dados de Sequência Molecular
RNA Catalítico/química
RNA Catalítico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (RNA, Catalytic); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1304
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130207
[St] Status:MEDLINE
[do] DOI:10.1021/bi301646n


  5 / 740 MEDLINE  
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[PMID]:22949672
[Au] Autor:Englert M; Xia S; Okada C; Nakamura A; Tanavde V; Yao M; Eom SH; Konigsberg WH; Söll D; Wang J
[Ad] Endereço:Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA.
[Ti] Título:Structural and mechanistic insights into guanylylation of RNA-splicing ligase RtcB joining RNA between 3'-terminal phosphate and 5'-OH.
[So] Source:Proc Natl Acad Sci U S A;109(38):15235-40, 2012 Sep 18.
[Is] ISSN:1091-6490
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The RtcB protein has recently been identified as a 3'-phosphate RNA ligase that directly joins an RNA strand ending with a 2',3'-cyclic phosphate to the 5'-hydroxyl group of another RNA strand in a GTP/Mn(2+)-dependent reaction. Here, we report two crystal structures of Pyrococcus horikoshii RNA-splicing ligase RtcB in complex with Mn(2+) alone (RtcB/ Mn(2+)) and together with a covalently bound GMP (RtcB-GMP/Mn(2+)). The RtcB/ Mn(2+) structure (at 1.6 Å resolution) shows two Mn(2+) ions at the active site, and an array of sulfate ions nearby that indicate the binding sites of the RNA phosphate backbone. The structure of the RtcB-GMP/Mn(2+) complex (at 2.3 Å resolution) reveals the detailed geometry of guanylylation of histidine 404. The critical roles of the key residues involved in the binding of the two Mn(2+) ions, the four sulfates, and GMP are validated in extensive mutagenesis and biochemical experiments, which also provide a thorough characterization for the three steps of the RtcB ligation pathway: (i) guanylylation of the enzyme, (ii) guanylyl-transfer to the RNA substrate, and (iii) overall ligation. These results demonstrate that the enzyme's substrate-induced GTP binding site and the putative reactive RNA ends are in the vicinity of the binuclear Mn(2+) active center, which provides detailed insight into how the enzyme-bound GMP is tansferred to the 3'-phosphate of the RNA substrate for activation and subsequent nucleophilic attack by the 5'-hydroxyl of the second RNA substrate, resulting in the ligated product and release of GMP.
[Mh] Termos MeSH primário: Aminoacil-tRNA Sintetases/química
Proteínas de Escherichia coli/química
Polinucleotídeo Ligases/química
Polinucleotídeo Ligases/genética
Pyrococcus horikoshii/metabolismo
[Mh] Termos MeSH secundário: Sítios de Ligação
Catálise
Domínio Catalítico
GMP Cíclico/química
Guanosina Trifosfato/química
Íons
Manganês/química
Modelos Moleculares
Conformação Molecular
Ligação Proteica
Processamento de RNA
RNA de Transferência/química
Especificidade por Substrato
Sulfatos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Escherichia coli Proteins); 0 (Ions); 0 (Sulfates); 42Z2K6ZL8P (Manganese); 86-01-1 (Guanosine Triphosphate); 9014-25-9 (RNA, Transfer); EC 6.1.1.- (Amino Acyl-tRNA Synthetases); EC 6.1.1.- (RtcB protein, E coli); EC 6.5.1.- (Polynucleotide Ligases); H2D2X058MU (Cyclic GMP)
[Em] Mês de entrada:1212
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120906
[St] Status:MEDLINE


  6 / 740 MEDLINE  
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[PMID]:22074260
[Au] Autor:Sato A; Soga T; Igarashi K; Takesue K; Tomita M; Kanai A
[Ad] Endereço:Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.
[Ti] Título:GTP-dependent RNA 3'-terminal phosphate cyclase from the hyperthermophilic archaeon Pyrococcus furiosus.
[So] Source:Genes Cells;16(12):1190-9, 2011 Dec.
[Is] ISSN:1365-2443
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We discovered that the PF1549 gene in Pyrococcus furiosus encodes a very heat-stable RNA 3'-terminal phosphate cyclase (Pf-Rtc). Although all previously reported Rtc proteins are ATP-dependent enzymes, we found that Pf-Rtc requires GTP for its cyclase activity at 95 °C. Low-level activation of the enzyme was also observed in the presence of dGTP but not other dNTPs, indicating that the guanine base is very important for Pf-Rtc activity. We analyzed a series of GTP analogues and found that the conversion from GTP to GMP is important for Pf-Rtc activity and that an excess of GMP inhibits this activity. Gel-shift analysis clearly showed that the RNA-binding activity of Pf-Rtc is totally dependent on the linear form of the 3'-terminal phosphate, with an apparent K(d) value of 20 nm at 95°C. Furthermore, we found that Pf-Rtc may contribute to GTP-dependent RNA ligation activity through the PF0027 protein (a 2'-5' RNA ligase-like protein in P. furiosus). The possible roles of Pf-Rtc and the importance of terminal phosphate structures in RNA are discussed.
[Mh] Termos MeSH primário: Guanosina Trifosfato/metabolismo
Ligases/metabolismo
Fosfatos/metabolismo
Polinucleotídeo Ligases/metabolismo
Pyrococcus furiosus/enzimologia
RNA/metabolismo
Proteínas Recombinantes/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Clonagem Molecular
Ensaio de Desvio de Mobilidade Eletroforética
Escherichia coli
Temperatura Alta
Cinética
Ligases/química
Ligases/genética
Ligases/isolamento & purificação
Dados de Sequência Molecular
Plasmídeos
Polinucleotídeo Ligases/genética
Pyrococcus furiosus/genética
RNA/genética
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Homologia de Sequência de Aminoácidos
Transformação Bacteriana
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Phosphates); 0 (Recombinant Proteins); 63231-63-0 (RNA); 86-01-1 (Guanosine Triphosphate); EC 6.- (Ligases); EC 6.5.- (RNA 3'-terminal phosphate cyclase); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1204
[Cu] Atualização por classe:111128
[Lr] Data última revisão:
111128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:111115
[St] Status:MEDLINE
[do] DOI:10.1111/j.1365-2443.2011.01561.x


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[PMID]:21930583
[Au] Autor:Piccirilli JA; Koldobskaya Y
[Ad] Endereço:Department of Biochemistry and Molecular Biology, The University of Chicago, Gordon Center for Integrative Science, Room W406, Chicago, IL 60637, USA. jpicciri@uchicago.edu
[Ti] Título:Crystal structure of an RNA polymerase ribozyme in complex with an antibody fragment.
[So] Source:Philos Trans R Soc Lond B Biol Sci;366(1580):2918-28, 2011 Oct 27.
[Is] ISSN:1471-2970
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:All models of the RNA world era invoke the presence of ribozymes that can catalyse RNA polymerization. The class I ligase ribozyme selected in vitro 15 years ago from a pool of random RNA sequences catalyses formation of a 3',5'-phosphodiester linkage analogous to a single step of RNA polymerization. Recently, the three-dimensional structure of the ligase was solved in complex with U1A RNA-binding protein and independently in complex with an antibody fragment. The RNA adopts a tripod arrangement and appears to use a two-metal ion mechanism similar to protein polymerases. Here, we discuss structural implications for engineering a true polymerase ribozyme and describe the use of the antibody framework both as a portable chaperone for crystallization of other RNAs and as a platform for exploring steps in evolution from the RNA world to the RNA-protein world.
[Mh] Termos MeSH primário: Anticorpos Catalíticos/química
RNA Polimerases Dirigidas por DNA/química
Fragmentos Fab das Imunoglobulinas/química
RNA Catalítico/química
Ribonucleotídeos/química
[Mh] Termos MeSH secundário: Catálise
Domínio Catalítico
Conformação de Ácido Nucleico
Biblioteca de Peptídeos
Polinucleotídeo Ligases/química
Proteínas Recombinantes/química
Ribonucleoproteínas/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Catalytic); 0 (Immunoglobulin Fab Fragments); 0 (Peptide Library); 0 (RNA, Catalytic); 0 (Recombinant Proteins); 0 (Ribonucleoproteins); 0 (Ribonucleotides); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1201
[Cu] Atualização por classe:150129
[Lr] Data última revisão:
150129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110921
[St] Status:MEDLINE
[do] DOI:10.1098/rstb.2011.0144


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[PMID]:21354310
[Au] Autor:Paredes E; Evans M; Das SR
[Ad] Endereço:Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
[Ti] Título:RNA labeling, conjugation and ligation.
[So] Source:Methods;54(2):251-9, 2011 Jun.
[Is] ISSN:1095-9130
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Advances in RNA nanotechnology will depend on the ability to manipulate, probe the structure and engineer the function of RNA with high precision. This article reviews current abilities to incorporate site-specific labels or to conjugate other useful molecules to RNA either directly or indirectly through post-synthetic labeling methodologies that have enabled a broader understanding of RNA structure and function. Readily applicable modifications to RNA can range from isotopic labels and fluorescent or other molecular probes to protein, lipid, glycoside or nucleic acid conjugates that can be introduced using combinations of synthetic chemistry, enzymatic incorporation and various conjugation chemistries. These labels, conjugations and ligations to RNA are quintessential for further investigation and applications of RNA as they enable the visualization, structural elucidation, localization, and biodistribution of modified RNA.
[Mh] Termos MeSH primário: Sondas RNA/biossíntese
Sondas RNA/síntese química
RNA/química
[Mh] Termos MeSH secundário: RNA Polimerases Dirigidas por DNA/química
Indicadores e Reagentes/química
Polinucleotídeo 5'-Hidroxiquinase/química
Polinucleotídeo Adenililtransferase/química
Polinucleotídeo Ligases/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Indicators and Reagents); 0 (RNA Probes); 63231-63-0 (RNA); EC 2.7.1.78 (Polynucleotide 5'-Hydroxyl-Kinase); EC 2.7.7.19 (Polynucleotide Adenylyltransferase); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1109
[Cu] Atualização por classe:110613
[Lr] Data última revisão:
110613
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110301
[St] Status:MEDLINE
[do] DOI:10.1016/j.ymeth.2011.02.008


  9 / 740 MEDLINE  
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[PMID]:20844078
[Au] Autor:Mori T; Ogasawara C; Inada T; Englert M; Beier H; Takezawa M; Endo T; Yoshihisa T
[Ad] Endereço:Department of Chemistry and Division of Biological Science, Graduate School of Science, and Research Center for Materials Science, Nagoya University, Nagoya 464-8602, Japan.
[Ti] Título:Dual functions of yeast tRNA ligase in the unfolded protein response: unconventional cytoplasmic splicing of HAC1 pre-mRNA is not sufficient to release translational attenuation.
[So] Source:Mol Biol Cell;21(21):3722-34, 2010 Nov 01.
[Is] ISSN:1939-4586
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The unfolded protein response (UPR) is an essential signal transduction to cope with protein-folding stress in the endoplasmic reticulum. In the yeast UPR, the unconventional splicing of HAC1 mRNA is a key step. Translation of HAC1 pre-mRNA (HAC1(u) mRNA) is attenuated on polysomes and restarted only after splicing upon the UPR. However, the precise mechanism of this restart remained unclear. Here we show that yeast tRNA ligase (Rlg1p/Trl1p) acting on HAC1 ligation has an unexpected role in HAC1 translation. An RLG1 homologue from Arabidopsis thaliana (AtRLG1) substitutes for yeast RLG1 in tRNA splicing but not in the UPR. Surprisingly, AtRlg1p ligates HAC1 exons, but the spliced mRNA (HAC1(i) mRNA) is not translated efficiently. In the AtRLG1 cells, the HAC1 intron is circularized after splicing and remains associated on polysomes, impairing relief of the translational repression of HAC1(i) mRNA. Furthermore, the HAC1 5' UTR itself enables yeast Rlg1p to regulate translation of the following ORF. RNA IP revealed that yeast Rlg1p is integrated in HAC1 mRNP, before Ire1p cleaves HAC1(u) mRNA. These results indicate that the splicing and the release of translational attenuation of HAC1 mRNA are separable steps and that Rlg1p has pivotal roles in both of these steps.
[Mh] Termos MeSH primário: Fatores de Transcrição de Zíper de Leucina Básica/genética
Diester Fosfórico Hidrolases/metabolismo
Polinucleotídeo 5´-Hidroxiquinase/metabolismo
Polinucleotídeo Ligases/metabolismo
Precursores de RNA/metabolismo
Proteínas Repressoras/genética
Proteínas de Saccharomyces cerevisiae/metabolismo
Saccharomyces cerevisiae/enzimologia
Resposta a Proteínas não Dobradas
[Mh] Termos MeSH secundário: Fatores de Transcrição de Zíper de Leucina Básica/biossíntese
Citoplasma/metabolismo
Regulação Fúngica da Expressão Gênica
Íntrons
Diester Fosfórico Hidrolases/genética
Polinucleotídeo 5'-Hidroxiquinase/genética
Polinucleotídeo Ligases/genética
Precursores de RNA/genética
Processamento de RNA
Proteínas Repressoras/biossíntese
Saccharomyces cerevisiae/genética
Proteínas de Saccharomyces cerevisiae/biossíntese
Proteínas de Saccharomyces cerevisiae/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Basic-Leucine Zipper Transcription Factors); 0 (HAC1 protein, S cerevisiae); 0 (RNA Precursors); 0 (Repressor Proteins); 0 (Saccharomyces cerevisiae Proteins); 0 (tRNA ligase, yeast); EC 2.7.1.78 (Polynucleotide 5'-Hydroxyl-Kinase); EC 3.1.4.- (Phosphoric Diester Hydrolases); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1102
[Cu] Atualização por classe:141202
[Lr] Data última revisão:
141202
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100917
[St] Status:MEDLINE
[do] DOI:10.1091/mbc.E10-08-0693


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[PMID]:20554706
[Au] Autor:Cheng LK; Unrau PJ
[Ad] Endereço:Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
[Ti] Título:Closing the circle: replicating RNA with RNA.
[So] Source:Cold Spring Harb Perspect Biol;2(10):a002204, 2010 Oct.
[Is] ISSN:1943-0264
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:How life emerged on this planet is one of the most important and fundamental questions of science. Although nearly all details concerning our origins have been lost in the depths of time, there is compelling evidence to suggest that the earliest life might have exploited the catalytic and self-recognition properties of RNA to survive. If an RNA based replicating system could be constructed in the laboratory, it would be much easier to understand the challenges associated with the very earliest steps in evolution and provide important insight into the establishment of the complex metabolic systems that now dominate this planet. Recent progress into the selection and characterization of ribozymes that promote nucleotide synthesis and RNA polymerization are discussed and outstanding problems in the field of RNA-mediated RNA replication are summarized.
[Mh] Termos MeSH primário: RNA Polimerases Dirigidas por DNA/metabolismo
Evolução Molecular
Polinucleotídeo Ligases/metabolismo
RNA Catalítico/metabolismo
RNA/biossíntese
[Mh] Termos MeSH secundário: RNA Polimerases Dirigidas por DNA/genética
Origem da Vida
Polinucleotídeo Ligases/genética
RNA/genética
RNA Catalítico/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (RNA, Catalytic); 63231-63-0 (RNA); EC 2.7.7.6 (DNA-Directed RNA Polymerases); EC 6.5.1.- (Polynucleotide Ligases)
[Em] Mês de entrada:1101
[Cu] Atualização por classe:160519
[Lr] Data última revisão:
160519
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:100618
[St] Status:MEDLINE
[do] DOI:10.1101/cshperspect.a002204



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