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[PMID]:29458668
[Au] Autor:Al-Ahmad A; Muzafferiy F; Anderson AC; Wölber JP; Ratka-Krüger P; Fretwurst T; Nelson K; Vach K; Hellwig E
[Ad] Endereço:1​Department of Operative Dentistry and Periodontology, Faculty of Medicine, Medical Center - University of Freiburg, Germany.
[Ti] Título:Shift of microbial composition of peri-implantitis-associated oral biofilm as revealed by 16S rRNA gene cloning.
[So] Source:J Med Microbiol;67(3):332-340, 2018 Mar.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Micro-organisms are important triggers of peri-implant inflammation and analysing their diversity is necessary for peri-implantitis treatment. This study aimed to analyse and compare the microbiota associated with individuals with peri-implantitis, as well as clinically healthy implant sites. METHODOLOGY: Subgingival biofilm samples were taken from 10 individuals with peri-implantitis and from at least 1 clinically healthy implant. DNA was extracted and bacterial 16S rRNA genes were amplified using universal primers. After cloning the PCR-products, amplified inserts of positive clones were digested using restriction endonucleases, and the chosen clones were sequenced. The 16S rDNA-sequences were compared to those from the public sequence databases GenBank, EMBL and DDBJ to determine the corresponding taxa. RESULTS: Differing distributions of taxa belonging to the phyla Firmicutes, Bacteroidetes, Fusobacteria, Actinobacteria, Proteobacteria, Synergistetes, Spirochaetae and TM 7 were detected in both the healthy implant (HI) and the peri-implantitis (PI) groups. A significantly higher relative abundance of phylum Bacteroidetes, as well as of the species Fusobacterium nucleatum, were found in the PI group (P<0.05). The putative periodontal red complex (Porphyromonas gingivalis, Tannerella forsythia) was also detected at significantly higher levels in the PI group (P<0.05), whereas the yellow group, as well as the species Veillonella dispar, tended to be associated with the HI group. CONCLUSION: A shift in the healthy subgingival microbiota was shown in peri-implantitis-associated biofilm. Anaerobic Gram-negative periopathogens, including P. gingivalis and T. forsythia, seem to play an important role in peri-implantitis development and should be considered in treatment and prevention strategies.
[Mh] Termos MeSH primário: Bactérias/isolamento & purificação
Biofilmes
Microbiota/genética
Peri-Implantite/microbiologia
RNA Ribossômico 16S/genética
[Mh] Termos MeSH secundário: Idoso
Idoso de 80 Anos ou mais
Bactérias/classificação
Bactérias/genética
Carga Bacteriana
Fenômenos Fisiológicos Bacterianos
Bacteroides/genética
Bacteroides/isolamento & purificação
Feminino
Fusobacterium nucleatum/genética
Fusobacterium nucleatum/isolamento & purificação
Genes de RNAr
Gengiva/microbiologia
Seres Humanos
Masculino
Meia-Idade
Porphyromonas gingivalis/genética
Porphyromonas gingivalis/isolamento & purificação
Prevotella intermedia/genética
Prevotella intermedia/isolamento & purificação
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000682


  2 / 6532 MEDLINE  
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[PMID]:29372965
[Au] Autor:Punina EO; Machs EM; Krapivskaya EE; Rodionov AV
[Ti] Título:[Polymorphic sites in transcribed spacers of 35S rRNA genes as an indicator of origin of the Paeonia cultivars].
[So] Source:Genetika;53(2):181-91, 2017 Feb.
[Is] ISSN:0016-6758
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Region ITS1­5.8S rDNA­ITS2 is sequenced in 27 varieties of cultivated ornamental peonies, ten of which presumably originate from Paeonia lactiflora, one from P. officinalis, 13 from hybridization of P. lactiflora and P. peregrina, or P. officinalis, and three are Itoh hybrids. Comparative analysis of distribution patterns of polymorphic sites (PS) for the obtained DNA sequences and data from GenBank is carried out. Hypotheses of origin of the studied varieties, except for two, which, as previously assumed, originate from hybridization of P. lactiflora and P. peregrina, are confirmed. It is shown that the sequence ITS1­5.8S rDNA­ITS2 is a good genetic marker for cultivars of the P. lactiflora group and Itoh hybrids, and that the PS distribution patterns in these sequences can provide valuable information on the kinship and origin of individual varieties. However, insufficient knowledge of wild species from the P. officinalis kinship group limits the use of this marker in the study of varieties obtained through interspecific hybridization within the Paeonia section.
[Mh] Termos MeSH primário: Genes de Plantas
Genes de RNAr
Paeonia/genética
Polimorfismo Genético
RNA de Plantas/genética
RNA Ribossômico/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (RNA, Plant); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180127
[St] Status:MEDLINE


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[PMID]:28459502
[Au] Autor:Kim KS; Jung JH; Min GS
[Ad] Endereço:Department of Biological Sciences, Inha University, 100 Inha-ro, Nam-gu, Incheon, 22212, South Korea.
[Ti] Título:Morphology and Molecular Phylogeny of Two New Ciliates, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp. (Ciliophora: Urostylida).
[So] Source:J Eukaryot Microbiol;64(6):873-884, 2017 Nov.
[Is] ISSN:1550-7408
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Two new urostylid species, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp., were discovered in South Korea. Morphological and phylogenetic analyses were carried out to confirm that these species are new to science. Holostichides heterotypicus is mainly characterized by the following combination of features: 110-205 µm long in vivo; 5-10 frontoterminal cirri; 6-8 midventral pairs with 2-3 midventral cirral rows; cortical granules present; four bipolar dorsal kineties; and 6-9 caudal cirri. Ontogenetic features of H. heterotypicus are similar to those of H. typicus. Phylogenetic analyses revealed that H. heterotypicus was distantly separated from bakuellid genera Apobakuella, Bakuella, Metaurostylopsis, and Neobakuella. This result is supported by the following features: transverse cirri (present in the other four bakuellids vs. absent in Holostichides) and caudal cirri (absent in the other four bakuellids vs. present in Holostichides). Holosticha muuiensis n. sp. is mainly distinguished from its congeners by the following combination of features: 100-185 long in vivo; shortened undulating membrane; cortical granules lacking; contractile vacuole absent; 51-66 adoral zone of membranelles; 42-60 macronuclear nodules; and five bipolar dorsal kineties. In the phylogenetic tree, Holosticha muuiensis n. sp. clustered with a Holosticha group (containing Holosticha diademata, Holosticha foissneri, and Holosticha heterofoissneri).
[Mh] Termos MeSH primário: Cilióforos/classificação
Filogenia
[Mh] Termos MeSH secundário: Cilióforos/citologia
Cilióforos/genética
Cilióforos/isolamento & purificação
Análise por Conglomerados
DNA de Protozoário/química
DNA de Protozoário/genética
DNA Ribossômico/química
DNA Ribossômico/genética
Genes de RNAr
Microscopia
RNA de Protozoário/genética
RNA Ribossômico 18S/genética
República da Coreia
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Protozoan); 0 (DNA, Ribosomal); 0 (RNA, Protozoan); 0 (RNA, Ribosomal, 18S)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1111/jeu.12421


  4 / 6532 MEDLINE  
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[PMID]:28456843
[Au] Autor:Mirzaghaderi G; Abdolmalaki Z; Zohouri M; Moradi Z; Mason AS
[Ad] Endereço:Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Kurdistan, P. O. Box 416, Sanandaj, Iran. gh.mirzaghaderi@uok.ac.ir.
[Ti] Título:Dynamic nucleolar activity in wheat × Aegilops hybrids: evidence of C-genome dominance.
[So] Source:Plant Cell Rep;36(8):1277-1285, 2017 Aug.
[Is] ISSN:1432-203X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:KEY MESSAGE: NOR loci of C-subgenome are dominant in wheat × Aegilops interspecific hybrids, which may have evolutionary implications for wheat group genome dynamics and evolution. After interspecific hybridisation, some genes are often expressed from only one of the progenitor species, shaping subsequent allopolyploid genome evolution processes. A well-known example is nucleolar dominance, i.e. the formation of cell nucleoli from chromosomes of only one parental species. We studied nucleolar organizing regions (NORs) in diploid Aegilops markgrafii (syn: Ae. caudata; CC), Ae. umbellulata (UU), allotetraploids Aegilops cylindrica (C C D D ) and Ae. triuncialis (C C U U ), synthetic interspecific F hybrids between these two allotetraploids and bread wheat (Triticum aestivum, AABBDD) and in F generation hybrids with genome composition AABBDDC C U U using silver staining and fluorescence in situ hybridization (FISH). In Ae. markgrafii (CC), NORs of both 1C and 5C or only 5C chromosome pairs were active in different individual cells, while only NORs on 1U chromosomes were active in Ae. umbellulata (UU). Although all 35S rDNA loci of the C subgenome (located on 1C and 5C ) were active in Ae. triuncialis, only one pair (occupying either 1C or 5C ) was active in Ae. cylindrica, depending on the genotype studied. These C-genome expression patterns were transmitted to the F and F generations. Wheat chromosome NOR activity was variable in Ae. triuncialis × T. aestivum F seeds, but silenced by the F generation. No effect of maternal or paternal cross direction was observed. These results indicate that C-subgenome NOR loci are dominant in wheat × Aegilops interspecific hybrids, which may have evolutionary implications for wheat group genome dynamics and allopolyploid evolution.
[Mh] Termos MeSH primário: Genoma de Planta/genética
Poaceae/genética
Triticum/genética
[Mh] Termos MeSH secundário: Cromossomos de Plantas/genética
Genes de RNAr/genética
Hibridização in Situ Fluorescente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180102
[Lr] Data última revisão:
180102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170501
[St] Status:MEDLINE
[do] DOI:10.1007/s00299-017-2152-x


  5 / 6532 MEDLINE  
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[PMID]:28968395
[Au] Autor:Chua TH; Manin BO; Daim S; Vythilingam I; Drakeley C
[Ad] Endereço:Department of Pathobiology and Medical Diagnostics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia.
[Ti] Título:Phylogenetic analysis of simian Plasmodium spp. infecting Anopheles balabacensis Baisas in Sabah, Malaysia.
[So] Source:PLoS Negl Trop Dis;11(10):e0005991, 2017 Oct.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Anopheles balabacensis of the Leucospyrus group has been confirmed as the primary knowlesi malaria vector in Sabah, Malaysian Borneo for some time now. Presently, knowlesi malaria is the only zoonotic simian malaria in Malaysia with a high prevalence recorded in the states of Sabah and Sarawak. METHODOLOGY/PRINCIPAL FINDINGS: Anopheles spp. were sampled using human landing catch (HLC) method at Paradason village in Kudat district of Sabah. The collected Anopheles were identified morphologically and then subjected to total DNA extraction and polymerase chain reaction (PCR) to detect Plasmodium parasites in the mosquitoes. Identification of Plasmodium spp. was confirmed by sequencing the SSU rRNA gene with species specific primers. MEGA4 software was then used to analyse the SSU rRNA sequences and bulid the phylogenetic tree for inferring the relationship between simian malaria parasites in Sabah. PCR results showed that only 1.61% (23/1,425) of the screened An. balabacensis were infected with one or two of the five simian Plasmodium spp. found in Sabah, viz. Plasmodium coatneyi, P. inui, P. fieldi, P. cynomolgi and P. knowlesi. Sequence analysis of SSU rRNA of Plasmodium isolates showed high percentage of identity within the same Plasmodium sp. group. The phylogenetic tree based on the consensus sequences of P. knowlesi showed 99.7%-100.0% nucleotide identity among the isolates from An. balabacensis, human patients and a long-tailed macaque from the same locality. CONCLUSIONS/SIGNIFICANCE: This is the first study showing high molecular identity between the P. knowlesi isolates from An. balabacensis, human patients and a long-tailed macaque in Sabah. The other common simian Plasmodium spp. found in long-tailed macaques and also detected in An. balabacensis were P. coatneyi, P. inui, P. fieldi and P. cynomolgi. The high percentage identity of nucleotide sequences between the P. knowlesi isolates from the long-tailed macaque, An. balabacensis and human patients suggests a close genetic relationship between the parasites from these hosts.
[Mh] Termos MeSH primário: Anopheles/parasitologia
Doenças dos Macacos/parasitologia
Plasmodium knowlesi/classificação
Plasmodium knowlesi/genética
[Mh] Termos MeSH secundário: Animais
DNA de Protozoário/genética
Genes de RNAr
Macaca fascicularis/parasitologia
Malária/epidemiologia
Malária/parasitologia
Malária/transmissão
Malária/veterinária
Malásia/epidemiologia
Filogenia
Reação em Cadeia da Polimerase
RNA de Protozoário/genética
RNA Ribossômico/genética
Zoonoses/epidemiologia
Zoonoses/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Protozoan); 0 (RNA, Protozoan); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171003
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005991


  6 / 6532 MEDLINE  
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[PMID]:28884677
[Au] Autor:Morais CG; Batista TM; Kominek J; Borelli BM; Furtado C; Moreira RG; Franco GR; Rosa LH; Fonseca C; Hittinger CT; Lachance MA; Rosa CA
[Ad] Endereço:1​Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, MG, 31270-901, Brazil.
[Ti] Título:Spathaspora boniae sp. nov., a D-xylose-fermenting species in the Candida albicans/Lodderomyces clade.
[So] Source:Int J Syst Evol Microbiol;67(10):3798-3805, 2017 Oct.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Two yeast isolates producing asci-containing elongate ascospores with curved ends typical of the genus Spathaspora were isolated from rotting wood samples collected in an Atlantic rainforest ecosystem in Brazil. Phylogenetic analysis of the LSU rRNA gene D1/D2 domain sequences demonstrated that the strains represent a new species and placed it next to Candida blackwellae, in a clade that also contains Candida albicans and Candida dubliniensis. Other sequences of the ribosomal gene cluster supported same placementin the same clade, and a phylogenomic analysis placed this new species in an early emerging position relative to the larger C. albicans/Lodderomyces clade. One interpretation is that the genus Spathaspora is, in fact, paraphyletic. In conformity with this view, we propose the novel species Spathaspora boniae sp. nov. to accommodate the isolates. The type strain of Spathaspora boniae sp. nov. is UFMG-CM-Y306 (=CBS 13262 ). The MycoBank number is MB 821297. A detailed analysis of xylose metabolism was conducted for the new species.
[Mh] Termos MeSH primário: Filogenia
Saccharomycetales/classificação
Madeira/microbiologia
Xilose/metabolismo
[Mh] Termos MeSH secundário: Brasil
DNA Fúngico/genética
Fermentação
Genes de RNAr
Técnicas de Tipagem Micológica
RNA Ribossômico 16S/genética
Saccharomycetales/genética
Saccharomycetales/isolamento & purificação
Análise de Sequência de DNA
Esporos Fúngicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Fungal); 0 (RNA, Ribosomal, 16S); A1TA934AKO (Xylose)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171027
[Lr] Data última revisão:
171027
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170909
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002186


  7 / 6532 MEDLINE  
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[PMID]:28758633
[Au] Autor:Boontham W; Limtong S; Rosa CA; Lopes MR; Vital MJS; Srisuk N
[Ad] Endereço:1​Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok, Thailand.
[Ti] Título:Cyberlindnera tropicalis f.a., sp. nov., a novel yeast isolated from tropical regions.
[So] Source:Int J Syst Evol Microbiol;67(8):2569-2573, 2017 Aug.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Two yeast strains, DMKU-WBBC14 and UFMG-CM-Y3283, were isolated from soil in Samutprakarn province in the central part of Thailand and from rotting wood in an Amazonian forest site in the Roraima State in Brazil, respectively. The two strains showed identical sequences of the D1/D2 domain of the large subunit (LSU) rRNA gene and different sequences by three nucleotide substitutions of the internal transcribed spacer (ITS) region. Therefore, these two strains represented a single species which was most closely related to Cyberlindnera mengyuniae CBS 10845T. The nucleotide sequence differences between the two strains of the novel species and the type strain Cyberlindnera mengyuniae CBS 10845T were 10 substitutions in the D1/D2 region of the LSU rRNA gene and 46 substitutions in the ITS region. DMKU-WBBC14 and UFMG-CM-Y3283 differed in growth temperature profiles. Moreover, they also exhibited different carbon assimilation profiles and growth temperature profiles from the type strain of Cyberlindnera mengyuniae, CBS 10845T. The name Cyberlindnera tropicalis f.a., sp. nov. is proposed. The type strain is DMKU-WBBC14T (=CBS 14558T=TBRC 6562T). The Mycobank number is MB 819722.
[Mh] Termos MeSH primário: Filogenia
Saccharomycetales/classificação
Madeira/microbiologia
[Mh] Termos MeSH secundário: Brasil
DNA Fúngico/genética
DNA Espaçador Ribossômico/genética
Genes de RNAr
Técnicas de Tipagem Micológica
Saccharomycetales/genética
Saccharomycetales/isolamento & purificação
Análise de Sequência de DNA
Microbiologia do Solo
Tailândia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Fungal); 0 (DNA, Ribosomal Spacer)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170914
[Lr] Data última revisão:
170914
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170801
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.001970


  8 / 6532 MEDLINE  
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[PMID]:28721840
[Au] Autor:Naumov GI; Naumova ES; Lee CF
[Ad] Endereço:1​State Institute for Genetics and Selection of Industrial Microorganisms, Moscow 117545, Russia.
[Ti] Título:Ogataea haglerorum sp. nov., a novel member of the species complex, Ogataea (Hansenula) polymorpha.
[So] Source:Int J Syst Evol Microbiol;67(7):2465-2469, 2017 Jul.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Three strains representing a novel species of the Ogataea clade were isolated by W. T. Starmer and H. J. Phaff from rotting tissue of Opuntia phaeacantha in Arizona, USA. Analyses of the sequences of the D1/D2 LSU rRNA gene, ITS1-5.8S-ITS2, and translation elongation factor-1α (EF-1 α) showed that this novel species belongs to the Ogataea polymorpha complex formed by Ogataea angusta, Ogataea parapolymorpha and Ogataea polymorpha. The novel species differs from these species by 4-5 nucleotide substitutions in the D1/D2 domain, by 28-29 nucleotide substitutions in the EF-α gene and by 18-24 nucleotide substitutions and 2-5 indels in the ITS-5.8S region. The name Ogataea haglerorum sp. nov. is proposed for this novel species. The type strain is VKPM Y-2583T (=CBS 14645T=UCDFST 17-101T). The Mycobank number is MB 819772.
[Mh] Termos MeSH primário: Opuntia/microbiologia
Filogenia
Saccharomycetales/classificação
[Mh] Termos MeSH secundário: Arizona
DNA Fúngico/genética
DNA Espaçador Ribossômico/genética
Genes de RNAr
Técnicas de Tipagem Micológica
Fator 1 de Elongação de Peptídeos/genética
Saccharomycetales/genética
Saccharomycetales/isolamento & purificação
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Fungal); 0 (DNA, Ribosomal Spacer); 0 (Peptide Elongation Factor 1)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170908
[Lr] Data última revisão:
170908
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170720
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002012


  9 / 6532 MEDLINE  
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[PMID]:28715449
[Au] Autor:Herdman C; Mars JC; Stefanovsky VY; Tremblay MG; Sabourin-Felix M; Lindsay H; Robinson MD; Moss T
[Ad] Endereço:Laboratory of Growth and Development, St-Patrick Research Group in Basic Oncology, Cancer Division of the Quebec University Hospital Research Centre, Québec, Canada.
[Ti] Título:A unique enhancer boundary complex on the mouse ribosomal RNA genes persists after loss of Rrn3 or UBF and the inactivation of RNA polymerase I transcription.
[So] Source:PLoS Genet;13(7):e1006899, 2017 Jul.
[Is] ISSN:1553-7404
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Transcription of the several hundred of mouse and human Ribosomal RNA (rRNA) genes accounts for the majority of RNA synthesis in the cell nucleus and is the determinant of cytoplasmic ribosome abundance, a key factor in regulating gene expression. The rRNA genes, referred to globally as the rDNA, are clustered as direct repeats at the Nucleolar Organiser Regions, NORs, of several chromosomes, and in many cells the active repeats are transcribed at near saturation levels. The rDNA is also a hotspot of recombination and chromosome breakage, and hence understanding its control has broad importance. Despite the need for a high level of rDNA transcription, typically only a fraction of the rDNA is transcriptionally active, and some NORs are permanently silenced by CpG methylation. Various chromatin-remodelling complexes have been implicated in counteracting silencing to maintain rDNA activity. However, the chromatin structure of the active rDNA fraction is still far from clear. Here we have combined a high-resolution ChIP-Seq protocol with conditional inactivation of key basal factors to better understand what determines active rDNA chromatin. The data resolve questions concerning the interdependence of the basal transcription factors, show that preinitiation complex formation is driven by the architectural factor UBF (UBTF) independently of transcription, and that RPI termination and release corresponds with the site of TTF1 binding. They further reveal the existence of an asymmetric Enhancer Boundary Complex formed by CTCF and Cohesin and flanked upstream by phased nucleosomes and downstream by an arrested RNA Polymerase I complex. We find that the Enhancer Boundary Complex is the only site of active histone modification in the 45kbp rDNA repeat. Strikingly, it not only delimits each functional rRNA gene, but also is stably maintained after gene inactivation and the re-establishment of surrounding repressive chromatin. Our data define a poised state of rDNA chromatin and place the Enhancer Boundary Complex as the likely entry point for chromatin remodelling complexes.
[Mh] Termos MeSH primário: Genes de RNAr
Proteínas Pol1 do Complexo de Iniciação de Transcrição/genética
RNA Polimerase I/metabolismo
[Mh] Termos MeSH secundário: Animais
Células Cultivadas
Montagem e Desmontagem da Cromatina
Elementos Facilitadores Genéticos
Feminino
Deleção de Genes
Inativação Gênica
Loci Gênicos
Camundongos
Camundongos Knockout
Proteínas Nucleares/genética
Proteínas Nucleares/metabolismo
Região Organizadora do Nucléolo/genética
Região Organizadora do Nucléolo/metabolismo
Proteínas Pol1 do Complexo de Iniciação de Transcrição/metabolismo
Gravidez
RNA Polimerase I/genética
Análise de Sequência de DNA
Fatores de Transcrição/genética
Fatores de Transcrição/metabolismo
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nuclear Proteins); 0 (Pol1 Transcription Initiation Complex Proteins); 0 (Rrn3 protein, mouse); 0 (Transcription Factors); 0 (transcription factor UBF); 0 (transcriptional intermediary factor 1); EC 2.7.7.6 (RNA Polymerase I)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170718
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pgen.1006899


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[PMID]:28704445
[Au] Autor:Tapio I; Fischer D; Blasco L; Tapio M; Wallace RJ; Bayat AR; Ventto L; Kahala M; Negussie E; Shingfield KJ; Vilkki J
[Ad] Endereço:Green Technology, Natural Resources Institute Finland, Jokioinen, Finland.
[Ti] Título:Taxon abundance, diversity, co-occurrence and network analysis of the ruminal microbiota in response to dietary changes in dairy cows.
[So] Source:PLoS One;12(7):e0180260, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The ruminal microbiome, comprising large numbers of bacteria, ciliate protozoa, archaea and fungi, responds to diet and dietary additives in a complex way. The aim of this study was to investigate the benefits of increasing the depth of the community analysis in describing and explaining responses to dietary changes. Quantitative PCR, ssu rRNA amplicon based taxa composition, diversity and co-occurrence network analyses were applied to ruminal digesta samples obtained from four multiparous Nordic Red dairy cows fitted with rumen cannulae. The cows received diets with forage:concentrate ratio either 35:65 (diet H) or 65:35 (L), supplemented or not with sunflower oil (SO) (0 or 50 g/kg diet dry matter), supplied in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments and four 35-day periods. Digesta samples were collected on days 22 and 24 and combined. QPCR provided a broad picture in which a large fall in the abundance of fungi was seen with SO in the H but not the L diet. Amplicon sequencing showed higher community diversity indices in L as compared to H diets and revealed diet specific taxa abundance changes, highlighting large differences in protozoal and fungal composition. Methanobrevibacter ruminantium and Mbb. gottschalkii dominated archaeal communities, and their abundance correlated negatively with each other. Co-occurrence network analysis provided evidence that no microbial domain played a more central role in network formation, that some minor-abundance taxa were at nodes of highest centrality, and that microbial interactions were diet specific. Networks added new dimensions to our understanding of the diet effect on rumen microbial community interactions.
[Mh] Termos MeSH primário: Archaea/classificação
Bactérias/classificação
Cilióforos/classificação
Dieta/veterinária
Fungos/classificação
Rúmen/microbiologia
[Mh] Termos MeSH secundário: Fenômenos Fisiológicos da Nutrição Animal
Animais
Archaea/genética
Archaea/isolamento & purificação
Bactérias/genética
Bactérias/isolamento & purificação
Biodiversidade
Bovinos
Cilióforos/genética
Cilióforos/isolamento & purificação
Feminino
Fungos/genética
Fungos/isolamento & purificação
Genes de RNAr
Microbiota
Análise de Sequência de DNA/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170714
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180260



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