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Pesquisa : D03.383.742.680.245 [Categoria DeCS]
Referências encontradas : 2314 [refinar]
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  1 / 2314 MEDLINE  
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[PMID]:29305868
[Au] Autor:Tominaga A; Sato M; Takahashi T; Toyoda E; Toyoda K; Suzuki T; Takahashi M; Watanabe M; Okazaki K
[Ad] Endereço:Department of Orthopaedic Surgery, Tokyo Women's Medical University, 8-1 Kawadacho, Shinjuku-ku, Tokyo, 162-8666, Japan.
[Ti] Título:Quality assessment of cellular and tissue-based products using liquid chromatography-tandem mass spectrometry.
[So] Source:Biochem Biophys Res Commun;496(2):429-435, 2018 02 05.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We are currently conducting clinical research on cell sheets for cartilage regeneration. One issue with the future use of chondrocyte sheets as cellular and tissue-based products is quality assessment. Currently, chondrocyte sheets are evaluated using invasive methods that cannot be performed on every sheet produced. We report here on our liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique that allows the noninvasive assessment of every sheet using only 50 µl of culture medium. We found that LC-MS/MS could be used to confirm cell sheet viability through the measurement of glucose and glutamine uptake, to estimate extracellular matrix production by measuring serine consumption, to estimate cell kinetics by measuring cytidine and uracil concentrations, and to estimate melanoma inhibitory activity level by measuring pyridoxal concentration. LC-MS/MS may be useful for the noninvasive assessment of products to be used in regenerative medicine.
[Mh] Termos MeSH primário: Cartilagem/metabolismo
Condrócitos/metabolismo
Cromatografia Líquida/normas
Regeneração/fisiologia
Espectrometria de Massas em Tandem/normas
[Mh] Termos MeSH secundário: Transporte Biológico
Cartilagem/patologia
Cartilagem/cirurgia
Citidina/metabolismo
Matriz Extracelular
Glucose/metabolismo
Glutamina/metabolismo
Seres Humanos
Controle de Qualidade
Medicina Regenerativa/métodos
Serina/metabolismo
Uracila/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0RH81L854J (Glutamine); 452VLY9402 (Serine); 56HH86ZVCT (Uracil); 5CSZ8459RP (Cytidine); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180107
[St] Status:MEDLINE


  2 / 2314 MEDLINE  
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[PMID]:28655767
[Au] Autor:Xu L; Liu X; Sheng N; Oo KS; Liang J; Chionh YH; Xu J; Ye F; Gao YG; Dedon PC; Fu XY
[Ad] Endereço:From the Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, 117599 Singapore.
[Ti] Título:Three distinct 3-methylcytidine (m C) methyltransferases modify tRNA and mRNA in mice and humans.
[So] Source:J Biol Chem;292(35):14695-14703, 2017 Sep 01.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chemical RNA modifications are central features of epitranscriptomics, highlighted by the discovery of modified ribonucleosides in mRNA and exemplified by the critical roles of RNA modifications in normal physiology and disease. Despite a resurgent interest in these modifications, the biochemistry of 3-methylcytidine (m C) formation in mammalian RNAs is still poorly understood. However, the recent discovery of as the second gene responsible for m C presence in RNA in fission yeast raises the possibility that multiple enzymes are involved in m C formation in mammals as well. Here, we report the discovery and characterization of three distinct m C-contributing enzymes in mice and humans. We found that methyltransferase-like (METTL) 2 and 6 contribute m C in specific tRNAs and that METTL8 only contributes m C to mRNA. MS analysis revealed that there is an ∼30-40% and ∼10-15% reduction, respectively, in and null-mutant cells, of m C in total tRNA, and primer extension analysis located METTL2-modified m C at position 32 of tRNA isoacceptors and tRNA We also noted that METTL6 interacts with seryl-tRNA synthetase in an RNA-dependent manner, suggesting a role for METTL6 in modifying serine tRNA isoacceptors. , however, modified only mRNA, as determined by biochemical and genetic analyses in null-mutant mice and two human mutant cell lines. Our findings provide the first evidence of the existence of m C modification in mRNA, and the discovery of METTL8 as an mRNA m C writer enzyme opens the door to future studies of other m C epitranscriptomic reader and eraser functions.
[Mh] Termos MeSH primário: Citidina/análogos & derivados
Fígado/metabolismo
Metiltransferases/metabolismo
Processamento Pós-Transcricional do RNA
RNA Mensageiro/metabolismo
RNA de Transferência/metabolismo
[Mh] Termos MeSH secundário: Animais
Linhagem Celular
Citidina/metabolismo
Seres Humanos
Isoenzimas/genética
Isoenzimas/metabolismo
Fígado/enzimologia
Metilação
Metiltransferases/antagonistas & inibidores
Metiltransferases/química
Metiltransferases/genética
Camundongos
Camundongos Knockout
Camundongos Mutantes
Mutação
Interferência de RNA
RNA de Transferência de Arginina/metabolismo
RNA de Transferência de Serina/metabolismo
RNA de Transferência de Treonina/metabolismo
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/metabolismo
Serina-tRNA Ligase/química
Serina-tRNA Ligase/metabolismo
Especificidade por Substrato
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Isoenzymes); 0 (RNA, Messenger); 0 (RNA, Transfer, Arg); 0 (RNA, Transfer, Ser); 0 (RNA, Transfer, Thr); 0 (Recombinant Fusion Proteins); 2140-64-9 (3-methylcytidine); 5CSZ8459RP (Cytidine); 9014-25-9 (RNA, Transfer); EC 2.1.1.- (Methyltransferases); EC 6.1.1.11 (Serine-tRNA Ligase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170629
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.798298


  3 / 2314 MEDLINE  
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[PMID]:28637869
[Au] Autor:Chen Z; Eggerman TL; Bocharov AV; Baranova IN; Vishnyakova TG; Kurlander R; Patterson AP
[Ad] Endereço:From the Department of Laboratory Medicine, Clinical Center.
[Ti] Título:Heat shock proteins stimulate APOBEC-3-mediated cytidine deamination in the hepatitis B virus.
[So] Source:J Biol Chem;292(32):13459-13479, 2017 Aug 11.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Apolipoprotein B mRNA-editing enzyme catalytic subunit 3 (APOBEC-3) enzymes are cytidine deaminases that are broadly and constitutively expressed. They are often up-regulated during carcinogenesis and candidate genes for causing the major single-base substitution in cancer-associated DNA mutations. Moreover, APOBEC-3s are involved in host innate immunity against many viruses. However, how APOBEC-3 mutational activity is regulated in normal and pathological conditions remains largely unknown. Heat shock protein levels are often elevated in both carcinogenesis and viral infection and are associated with DNA mutations. Here, using mutational analyses of hepatitis B virus (HBV), we found that Hsp90 stimulates deamination activity of APOBEC-3G (A3G), A3B, and A3C during co-expression in human liver HepG2 cells. Hsp90 directly stimulated A3G deamination activity when the purified proteins were used in reactions. Hsp40, -60, and -70 also had variable stimulatory effects in the cellular assay, but not Sequencing analyses further demonstrated that Hsp90 increased both A3G cytosine mutation efficiency on HBV DNA and total HBV mutation frequency. In addition, Hsp90 shifted A3G's cytosine region selection in HBV DNA and increased A3G's 5' nucleoside preference for deoxycytidine (5'-CC). Furthermore, the Hsp90 inhibitor 17- -allylamino-17-demethoxygeldanamycin dose dependently inhibited A3G and A3B mutational activity on HBV viral DNA. Hsp90 knockdown by siRNA or by Hsp90 active-site mutation also decreased A3G activity. These results indicate that heat shock proteins, in particular Hsp90, stimulate APOBEC-3-mediated DNA deamination activity, suggesting a potential physiological role in carcinogenesis and viral innate immunity.
[Mh] Termos MeSH primário: Desaminase APOBEC-3G/metabolismo
Citidina Desaminase/metabolismo
DNA Viral/metabolismo
Proteínas de Choque Térmico HSP90/metabolismo
Vírus da Hepatite B/metabolismo
Hepatócitos/metabolismo
Antígenos de Histocompatibilidade Menor/metabolismo
[Mh] Termos MeSH secundário: Desaminase APOBEC-3G/química
Desaminase APOBEC-3G/genética
Carcinogênese
Citidina/metabolismo
Citidina Desaminase/química
Citidina Desaminase/genética
Análise Mutacional de DNA
DNA Recombinante/química
DNA Recombinante/metabolismo
DNA Viral/química
Desaminação
Proteínas de Choque Térmico HSP90/antagonistas & inibidores
Proteínas de Choque Térmico HSP90/genética
Células Hep G2
Vírus da Hepatite B/genética
Vírus da Hepatite B/imunologia
Hepatócitos/imunologia
Hepatócitos/virologia
Seres Humanos
Imunidade Inata
Antígenos de Histocompatibilidade Menor/química
Antígenos de Histocompatibilidade Menor/genética
Mutagênese
Taxa de Mutação
Fragmentos de Peptídeos/agonistas
Fragmentos de Peptídeos/genética
Fragmentos de Peptídeos/metabolismo
Mutação Puntual
Interferência de RNA
Proteínas Recombinantes de Fusão/química
Proteínas Recombinantes de Fusão/metabolismo
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Recombinant); 0 (DNA, Viral); 0 (HSP90 Heat-Shock Proteins); 0 (Minor Histocompatibility Antigens); 0 (Peptide Fragments); 0 (Recombinant Fusion Proteins); 0 (Recombinant Proteins); 5CSZ8459RP (Cytidine); EC 3.5.4.5 (APOBEC-3G Deaminase); EC 3.5.4.5 (APOBEC3B protein, human); EC 3.5.4.5 (APOBEC3C protein, human); EC 3.5.4.5 (APOBEC3G protein, human); EC 3.5.4.5 (Cytidine Deaminase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M116.760637


  4 / 2314 MEDLINE  
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[PMID]:28636622
[Au] Autor:Guillot C; Martel N; Berby F; Bordes I; Hantz O; Blanchet M; Sureau C; Vaillant A; Chemin I
[Ad] Endereço:Centre de Recherche en Cancérologie de Lyon INSERM U1052, CNRS UMR5286, Université de Lyon, Lyon, France.
[Ti] Título:Inhibition of hepatitis B viral entry by nucleic acid polymers in HepaRG cells and primary human hepatocytes.
[So] Source:PLoS One;12(6):e0179697, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hepatitis B virus (HBV) infection remains a major public health concern worldwide with 240 million individuals chronically infected and at risk of developing cirrhosis and hepatocellular carcinoma. Current treatments rarely cure chronic hepatitis B infection, highlighting the need for new anti-HBV drugs. Nucleic acid polymers (NAPs) are phosphorothioated oligonucleotides that have demonstrated a great potential to inhibit infection with several viruses. In chronically infected human patients, NAPs administration lead to a decline of blood HBsAg and HBV DNA and to HBsAg seroconversion, the expected signs of functional cure. NAPs have also been shown to prevent infection of duck hepatocytes with the Avihepadnavirus duck hepatitis B virus (DHBV) and to exert an antiviral activity against established DHBV infection in vitro and in vivo. In this study, we investigated the specific anti-HBV antiviral activity of NAPs in the HepaRG human hepatoma cell line and primary cultures of human hepatocytes. NAPs with different chemical features (phosphorothioation, 2'O-methyl ribose, 5-methylcytidine) were assessed for antiviral activity when provided at the time of HBV inoculation or post-inoculation. NAPs dose-dependently inhibited HBV entry in a phosphorothioation-dependent, sequence-independent and size-dependent manner. This inhibition of HBV entry by NAPs was impaired by 2'O-methyl ribose modification. NAP treatment after viral inoculation did not elicit any antiviral activity.
[Mh] Termos MeSH primário: Antivirais/farmacologia
Vírus da Hepatite B/fisiologia
Ácidos Nucleicos/química
Polímeros/farmacologia
Internalização do Vírus/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antivirais/química
Antivirais/toxicidade
Sobrevivência Celular/efeitos dos fármacos
Células Cultivadas
Citidina/análogos & derivados
Citidina/química
DNA Viral/sangue
Antígenos de Superfície da Hepatite B/sangue
Antígenos E da Hepatite B/sangue
Vírus da Hepatite B/genética
Hepatócitos/citologia
Hepatócitos/virologia
Seres Humanos
Imunoensaio
Fosfatos/química
Polímeros/química
Polímeros/toxicidade
Reação em Cadeia da Polimerase em Tempo Real
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antiviral Agents); 0 (DNA, Viral); 0 (Hepatitis B Surface Antigens); 0 (Hepatitis B e Antigens); 0 (Nucleic Acids); 0 (Phosphates); 0 (Polymers); 5CSZ8459RP (Cytidine); 8056RR93HU (phosphorodithioic acid); TL9PB228DC (5-methylcytidine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170622
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179697


  5 / 2314 MEDLINE  
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[PMID]:28585179
[Au] Autor:Liang P; Sun H; Sun Y; Zhang X; Xie X; Zhang J; Zhang Z; Chen Y; Ding C; Xiong Y; Ma W; Liu D; Huang J; Songyang Z
[Ad] Endereço:Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China. liangpp5@mail.sysu.edu.cn.
[Ti] Título:Effective gene editing by high-fidelity base editor 2 in mouse zygotes.
[So] Source:Protein Cell;8(8):601-611, 2017 Aug.
[Is] ISSN:1674-8018
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Targeted point mutagenesis through homologous recombination has been widely used in genetic studies and holds considerable promise for repairing disease-causing mutations in patients. However, problems such as mosaicism and low mutagenesis efficiency continue to pose challenges to clinical application of such approaches. Recently, a base editor (BE) system built on cytidine (C) deaminase and CRISPR/Cas9 technology was developed as an alternative method for targeted point mutagenesis in plant, yeast, and human cells. Base editors convert C in the deamination window to thymidine (T) efficiently, however, it remains unclear whether targeted base editing in mouse embryos is feasible. In this report, we generated a modified high-fidelity version of base editor 2 (HF2-BE2), and investigated its base editing efficacy in mouse embryos. We found that HF2-BE2 could convert C to T efficiently, with up to 100% biallelic mutation efficiency in mouse embryos. Unlike BE3, HF2-BE2 could convert C to T on both the target and non-target strand, expanding the editing scope of base editors. Surprisingly, we found HF2-BE2 could also deaminate C that was proximal to the gRNA-binding region. Taken together, our work demonstrates the feasibility of generating point mutations in mouse by base editing, and underscores the need to carefully optimize base editing systems in order to eliminate proximal-site deamination.
[Mh] Termos MeSH primário: Desaminase APOBEC-1/genética
Proteínas de Bactérias/genética
Sistemas CRISPR-Cas
Transferência Embrionária
Endonucleases/genética
Edição de Genes/métodos
Zigoto/metabolismo
[Mh] Termos MeSH secundário: Desaminase APOBEC-1/metabolismo
Animais
Proteínas de Bactérias/metabolismo
Sequência de Bases
Citidina/genética
Citidina/metabolismo
Embrião de Mamíferos
Endonucleases/metabolismo
Células HEK293
Sequenciamento de Nucleotídeos em Larga Escala
Seres Humanos
Camundongos
Camundongos Endogâmicos C57BL
Microinjeções
Plasmídeos/química
Plasmídeos/metabolismo
Mutação Puntual
RNA Guia/genética
RNA Guia/metabolismo
Timidina/genética
Timidina/metabolismo
Zigoto/crescimento & desenvolvimento
Zigoto/transplante
[Pt] Tipo de publicação:LETTER
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (RNA, Guide); 5CSZ8459RP (Cytidine); EC 3.1.- (Cas9 endonuclease Streptococcus pyogenes); EC 3.1.- (Endonucleases); EC 3.5.4.36 (APOBEC-1 Deaminase); VC2W18DGKR (Thymidine)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170824
[Lr] Data última revisão:
170824
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170607
[St] Status:MEDLINE
[do] DOI:10.1007/s13238-017-0418-2


  6 / 2314 MEDLINE  
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[PMID]:28576825
[Au] Autor:Schmitt FCF; Freund I; Weigand MA; Helm M; Dalpke AH; Eigenbrod T
[Ad] Endereço:Department of Anesthesiology, Heidelberg University Hospital, 69120 Heidelberg, Germany.
[Ti] Título:Identification of an optimized 2'- -methylated trinucleotide RNA motif inhibiting Toll-like receptors 7 and 8.
[So] Source:RNA;23(9):1344-1351, 2017 Sep.
[Is] ISSN:1469-9001
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial RNA serves an important function as activator of the innate immune system. In humans bacterial RNA is sensed by the endosomal receptors TLR7 and TLR8. Differences in the posttranscriptional modification profile of prokaryotic when compared with eukaryotic RNA allow innate immune cells to discriminate between "host" and "foreign" RNA. Ribose 2'- -methylation is of particular importance and has been reported to antagonize TLR7/8 activation. Yet, the exact sequence context in which 2'- -methylation has to occur to mediate its inhibitory activity remains largely undefined. On the basis of a naturally occurring 2'- -methylated RNA sequence, we performed a systematic permutation of the methylated nucleotide as well as adjacent bases and hereby identify two minimal trinucleotide motifs within a 9-mer oligoribonucleotide that are necessary and sufficient to antagonize TLR7 and TLR8 activation, respectively. Given the growing interest in the development of inhibitors of nucleic acid-sensing TLRs for therapeutic purposes, these results will facilitate the rational design of such antagonists in the future.
[Mh] Termos MeSH primário: Motivos de Nucleotídeos
RNA/genética
RNA/metabolismo
Receptor 7 Toll-Like/antagonistas & inibidores
Receptor 8 Toll-Like/antagonistas & inibidores
[Mh] Termos MeSH secundário: Citidina
Seres Humanos
Concentração Inibidora 50
Leucócitos Mononucleares
Metilação
Mutação
Nucleotídeos/química
Nucleotídeos/metabolismo
RNA/química
RNA Bacteriano/química
RNA Bacteriano/genética
RNA Bacteriano/metabolismo
RNA de Transferência/química
RNA de Transferência/genética
RNA de Transferência/metabolismo
Receptor 7 Toll-Like/metabolismo
Receptor 8 Toll-Like/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nucleotides); 0 (RNA, Bacterial); 0 (Toll-Like Receptor 7); 0 (Toll-Like Receptor 8); 5CSZ8459RP (Cytidine); 63231-63-0 (RNA); 9014-25-9 (RNA, Transfer)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170604
[St] Status:MEDLINE
[do] DOI:10.1261/rna.061952.117


  7 / 2314 MEDLINE  
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[PMID]:28571974
[Au] Autor:Wang L; Taniguchi Y; Okamura H; Sasaki S
[Ad] Endereço:School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
[Ti] Título:Effect of the 3-halo substitution of the 2'-deoxy aminopyridinyl-pseudocytidine derivatives on the selectivity and stability of antiparallel triplex DNA with a CG inversion site.
[So] Source:Bioorg Med Chem;25(14):3853-3860, 2017 Jul 15.
[Is] ISSN:1464-3391
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Triplex formation against a target duplex DNA has the potential to become a tool for the genome research. However, there is an intrinsic restriction on the duplex DNA sequences capable of forming the triplex DNA. Recently, we demonstrated the selective formation of the stable antiparallel triplexes containing the CG inversion sites using the 2'-deoxy-1-methylpseudocytidine derivative (ΨdC), whose amino group was conjugated with the 2-aminopyridine at its 5-position as an additional hydrogen bonding unit (AP-ΨdC). The 1-N of 2-aminopyridine was supposed to be protonated to form the hydrogen bond with the guanine of the CG inversion site. In this study, to test the effect of the 3-substitution of the 2-aminopyridine unit of AP-ΨdC on the triplex stability, we synthesized the 3-halogenated 2-aminopyridine derivatives of AP-ΨdC. The pKa values 1-N of the 2-aminopyridine unit of AP-ΨdC as the monomer nucleoside were determined to be 6.3 for 3-CH ( AP-ΨdC), 6.1 for 3-H (AP-ΨdC), 4.3 for 3-Cl ( AP-ΨdC), 4.4 for 3-Br ( AP-ΨdC), and 4.7 for 3-I ( AP-ΨdC), suggesting that all the halogenated AP-ΨdCs are not protonated under neutral conditions. Interestingly, although the recognition selectivity depends on the sequence context, the TFO having the sequence of the 3'-G-( AP-ΨdC)-A-5' context showed the selective triplex formation with the CG inversion site. These results suggest that the protonation at the 1-N position plays an important role in the stable and selective triplex formation of AP-ΨdC derivatives in any sequences.
[Mh] Termos MeSH primário: Citidina/análogos & derivados
DNA/química
[Mh] Termos MeSH secundário: Aminopiridinas/química
Sequência de Bases
Citidina/síntese química
Citidina/química
DNA/metabolismo
Halogênios/química
Ligações de Hidrogênio
Cinética
Espectroscopia de Ressonância Magnética
Conformação de Ácido Nucleico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2'-deoxy-1-methylpseudocytidine); 0 (Aminopyridines); 0 (Halogens); 0 (triplex DNA); 5CSZ8459RP (Cytidine); 9007-49-2 (DNA); WSX981HEWU (alpha-aminopyridine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170603
[St] Status:MEDLINE


  8 / 2314 MEDLINE  
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[PMID]:28549193
[Au] Autor:Glasner H; Riml C; Micura R; Breuker K
[Ad] Endereço:Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria.
[Ti] Título:Label-free, direct localization and relative quantitation of the RNA nucleobase methylations m6A, m5C, m3U, and m5U by top-down mass spectrometry.
[So] Source:Nucleic Acids Res;45(13):8014-8025, 2017 Jul 27.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Nucleobase methylations are ubiquitous posttranscriptional modifications of ribonucleic acids (RNA) that can substantially increase the structural diversity of RNA in a highly dynamic fashion with implications for gene expression and human disease. However, high throughput, deep sequencing does not generally provide information on posttranscriptional modifications (PTMs). A promising alternative approach for the characterization of PTMs, i.e. their identification, localization, and relative quantitation, is top-down mass spectrometry (MS). In this study, we have investigated how specific nucleobase methylations affect RNA ionization in electrospray ionization (ESI), and backbone cleavage in collisionally activated dissociation (CAD) and electron detachment dissociation (EDD). For this purpose, we have developed two new approaches for the characterization of RNA methylations in mixtures of either isomers of RNA or nonisomeric RNA forms. Fragment ions from dissociation experiments were analyzed to identify the modification type, to localize the modification sites, and to reveal the site-specific, relative extent of modification for each site.
[Mh] Termos MeSH primário: RNA/química
Espectrometria de Massas por Ionização por Electrospray/métodos
[Mh] Termos MeSH secundário: Adenosina/análogos & derivados
Adenosina/análise
Adenosina/química
Sequência de Bases
Citidina/análogos & derivados
Citidina/análise
Citidina/química
Íons
Metilação
Estrutura Molecular
Espectroscopia de Infravermelho com Transformada de Fourier/métodos
Uridina/análogos & derivados
Uridina/análise
Uridina/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 1463-10-1 (ribothymidine); 1867-73-8 (N(6)-methyladenosine); 2140-69-4 (3-methyluridine); 5CSZ8459RP (Cytidine); 63231-63-0 (RNA); K72T3FS567 (Adenosine); TL9PB228DC (5-methylcytidine); WHI7HQ7H85 (Uridine)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170527
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx470


  9 / 2314 MEDLINE  
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[PMID]:28472312
[Au] Autor:Kawarada L; Suzuki T; Ohira T; Hirata S; Miyauchi K; Suzuki T
[Ad] Endereço:Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
[Ti] Título:ALKBH1 is an RNA dioxygenase responsible for cytoplasmic and mitochondrial tRNA modifications.
[So] Source:Nucleic Acids Res;45(12):7401-7415, 2017 Jul 07.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:ALKBH1 is a 2-oxoglutarate- and Fe2+-dependent dioxygenase responsible for multiple cellular functions. Here, we show that ALKBH1 is involved in biogenesis of 5-hydroxymethyl-2΄-O-methylcytidine (hm5Cm) and 5-formyl-2΄-O-methylcytidine (f5Cm) at the first position (position 34) of anticodon in cytoplasmic tRNALeu, as well as f5C at the same position in mitochondrial tRNAMet. Because f5C34 of mitochondrial tRNAMet is essential for translation of AUA, a non-universal codon in mammalian mitochondria, ALKBH1-knockout cells exhibited a strong reduction in mitochondrial translation and reduced respiratory complex activities, indicating that f5C34 formation mediated by ALKBH1 is required for efficient mitochondrial functions. We reconstituted formation of f5C34 on mitochondrial tRNAMetin vitro, and found that ALKBH1 first hydroxylated m5C34 to form hm5C34, and then oxidized hm5C34 to form f5C34. Moreover, we found that the frequency of 1-methyladenosine (m1A) in two mitochondrial tRNAs increased in ALKBH1-knockout cells, indicating that ALKBH1 also has demethylation activity toward m1A in mt-tRNAs. Based on these results, we conclude that nuclear and mitochondrial ALKBH1 play distinct roles in tRNA modification.
[Mh] Termos MeSH primário: Homólogo AlkB 1 da Histona H2a Dioxigenase/genética
Citidina/análogos & derivados
Biossíntese de Proteínas
RNA de Transferência de Metionina/genética
[Mh] Termos MeSH secundário: Homólogo AlkB 1 da Histona H2a Dioxigenase/deficiência
Anticódon/química
Anticódon/metabolismo
Sequência de Bases
Sistemas CRISPR-Cas
Citidina/metabolismo
Citosol/metabolismo
Técnicas de Inativação de Genes
Teste de Complementação Genética
Células HEK293
Seres Humanos
Metiltransferases/genética
Metiltransferases/metabolismo
Mitocôndrias/metabolismo
Conformação de Ácido Nucleico
Oxirredução
Fosforilação Oxidativa
RNA de Transferência de Metionina/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (2'-O-methyl-5-formylcytidine); 0 (Anticodon); 0 (RNA, Transfer, Met); 148608-53-1 (5-formylcytidine); 5CSZ8459RP (Cytidine); EC 1.14.11.33 (ALKBH1 protein, human); EC 1.14.11.33 (AlkB Homolog 1, Histone H2a Dioxygenase); EC 2.1.1.- (Methyltransferases); EC 2.1.1.- (NSUN3 protein, human)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx354


  10 / 2314 MEDLINE  
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[PMID]:28398586
[Au] Autor:Mosley M; Weathington J; Cortes LR; Bruggeman E; Castillo-Ruiz A; Xue B; Forger NG
[Ad] Endereço:Neuroscience Institute and Center for Behavioral Neuroscience, Georgia State University, Atlanta, Georgia 30302.
[Ti] Título:Neonatal Inhibition of DNA Methylation Alters Cell Phenotype in Sexually Dimorphic Regions of the Mouse Brain.
[So] Source:Endocrinology;158(6):1838-1848, 2017 Jun 01.
[Is] ISSN:1945-7170
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Many of the best-studied neural sex differences relate to differences in cell number and are due to the hormonal control of developmental cell death. However, several prominent neural sex differences persist even if cell death is eliminated. We hypothesized that these may reflect cell phenotype "decisions" that depend on epigenetic mechanisms, such as DNA methylation. To test this, we treated newborn mice with the DNA methyltransferase (DNMT) inhibitor zebularine, or vehicle, and examined two sexually dimorphic markers at weaning. As expected, control males had more cells immunoreactive for calbindin-D28k (CALB) in the medial preoptic area (mPOA) and fewer cells immunoreactive for estrogen receptor α (ERα) in the ventrolateral portion of the ventromedial nucleus of the hypothalamus (VMHvl) and the mPOA than did females. Neonatal DNMT inhibition markedly increased CALB cell number in both sexes and ERα cell density in males; as a result, the sex differences in ERα in the VMHvl and mPOA were completely eliminated in zebularine-treated animals. Zebularine treatment did not affect developmental cell death or the total density of Nissl-stained cells at weaning. Thus, a neonatal disruption of DNA methylation apparently has long-term effects on the proportion of cells expressing CALB and ERα, and some of these effects are sex specific. We also found that sex differences in CALB in the mPOA and ERα in the VMHvl persist in mice with a neuron-specific depletion of either Dnmt1 or Dnmt3b, indicating that neither DNMT alone is likely to be required for the sexually dimorphic expression of these markers.
[Mh] Termos MeSH primário: Encéfalo/efeitos dos fármacos
Citidina/análogos & derivados
DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores
Metilação de DNA/efeitos dos fármacos
Neurônios/efeitos dos fármacos
Caracteres Sexuais
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Encéfalo/citologia
Encéfalo/crescimento & desenvolvimento
Citidina/farmacologia
DNA (Citosina-5-)-Metiltransferase 1
Regulação para Baixo/efeitos dos fármacos
Feminino
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Neurônios/citologia
Neurônios/fisiologia
Fenótipo
Processos de Determinação Sexual/efeitos dos fármacos
Processos de Determinação Sexual/genética
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
5CSZ8459RP (Cytidine); 7A9Y5SX0GY (pyrimidin-2-one beta-ribofuranoside); EC 2.1.1.37 (DNA (Cytosine-5-)-Methyltransferase 1); EC 2.1.1.37 (DNA (Cytosine-5-)-Methyltransferases); EC 2.1.1.37 (Dnmt1 protein, mouse)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170412
[St] Status:MEDLINE
[do] DOI:10.1210/en.2017-00205



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