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991.
The tomato res mutant which accumulates JA in roots in non‐stressed conditions restores cell structure alterations under salinity
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996.
Enrique Vázquez Francisco Antequera 《BioEssays : news and reviews in molecular, cellular and developmental biology》2015,37(10):1067-1073
The dynamics of eukaryotic DNA polymerases has been difficult to establish because of the difficulty of tracking them along the chromosomes during DNA replication. Recent work has addressed this problem in the yeasts Schizosaccharomyces pombe and Saccharomyces cerevisiae through the engineering of replicative polymerases to render them prone to incorporating ribonucleotides at high rates. Their use as tracers of the passage of each polymerase has provided a picture of unprecedented resolution of the organization of replicons and replication origins in the two yeasts and has uncovered important differences between them. Additional studies have found an overlapping distribution of DNA polymorphisms and the junctions of Okazaki fragments along mononucleosomal DNA. This sequence instability is caused by the premature release of polymerase δ and the retention of non proof‐read DNA tracts replicated by polymerase α. The possible implementation of these new experimental approaches in multicellular organisms opens the door to the analysis of replication dynamics under a broad range of genetic backgrounds and physiological or pathological conditions. 相似文献
997.
Eric?Roberto?Guimar?es?Rocha Aguiar Roenick Proveti Olmo Simona Paro Flavia Viana Ferreira Isaque?Jo?o?da?Silva de?Faria Yaovi?Mathias?Honore Todjro Francisco Pereira Lobo Erna Geessien Kroon Carine Meignin Derek Gatherer Jean-Luc Imler Jo?o Trindade Marques 《Nucleic acids research》2015,43(13):6191-6206
Virus surveillance in vector insects is potentially of great benefit to public health. Large-scale sequencing of small and long RNAs has previously been used to detect viruses, but without any formal comparison of different strategies. Furthermore, the identification of viral sequences largely depends on similarity searches against reference databases. Here, we developed a sequence-independent strategy based on virus-derived small RNAs produced by the host response, such as the RNA interference pathway. In insects, we compared sequences of small and long RNAs, demonstrating that viral sequences are enriched in the small RNA fraction. We also noted that the small RNA size profile is a unique signature for each virus and can be used to identify novel viral sequences without known relatives in reference databases. Using this strategy, we characterized six novel viruses in the viromes of laboratory fruit flies and wild populations of two insect vectors: mosquitoes and sandflies. We also show that the small RNA profile could be used to infer viral tropism for ovaries among other aspects of virus biology. Additionally, our results suggest that virus detection utilizing small RNAs can also be applied to vertebrates, although not as efficiently as to plants and insects. 相似文献
998.
Jaquelline Carla Valamiel de Oliveira-Silva Girley Francisco Machado-de-Assis Maykon Tavares Oliveira Nívia Carolina Noguieira Paiva Márcio Sobreira Silva Araújo Cláudia Martins Carneiro Olindo Assis Martins-Filho Helen Rodrigues Martins Marta de Lana 《Memórias do Instituto Oswaldo Cruz》2015,110(1):86-94
Trypanosoma cruzi strains from distinct geographic areas show differences in drug
resistance and association between parasites genetic and treatment response has been
observed. Considering that benznidazole (BZ) can reduce the parasite burden and
tissues damage, even in not cured animals and individuals, the goal is to assess the
drug response to BZ of T. cruzi II strains isolated from children of the
Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected
and treated with BZ in both phases of infection were compared with the untreated and
evaluated by fresh blood examination, haemoculture, polymerase chain reaction,
conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in
the acute phase, a significant decrease in parasitaemia was observed for all strains.
Positive parasitological and/or serological tests in animals treated during the acute
and chronic (95.1-100%) phases showed that most of the strains were BZ resistant.
However, beneficial effect was demonstrated because significant reduction (p <
0.05%) and/or suppression of parasitaemia was observed in mice infected with all
strains (acute phase), associated to reduction/elimination of inflammation and
fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals,
what suggest that BZ use may be recommended at least for recent chronic infection of
the studied region. 相似文献
999.
Claudio Hidalgo-Cantabrana Borja Sánchez Pablo álvarez-Martín Patricia López Noelia Martínez-álvarez Michele Delley Marc Martí Encarna Varela Ana Suárez María Antolín Francisco Guarner Bernard Berger Patricia Ruas-Madiedo Abelardo Margolles 《Applied and environmental microbiology》2015,81(23):7960-7968
Exopolysaccharides (EPS) are extracellular carbohydrate polymers synthesized by a large variety of bacteria. Their physiological functions have been extensively studied, but many of their roles have not yet been elucidated. We have sequenced the genomes of two isogenic strains of Bifidobacterium animalis subsp. lactis that differ in their EPS-producing phenotype. The original strain displays a nonmucoid appearance, and the mutant derived thereof has acquired a mucoid phenotype. The sequence analysis of their genomes revealed a nonsynonymous mutation in the gene Balat_1410, putatively involved in the elongation of the EPS chain. By comparing a strain from which this gene had been deleted with strains containing the wild-type and mutated genes, we were able to show that each strain displays different cell surface characteristics. The mucoid EPS synthesized by the strain harboring the mutation in Balat_1410 provided higher resistance to gastrointestinal conditions and increased the capability for adhesion to human enterocytes. In addition, the cytokine profiles of human peripheral blood mononuclear cells and ex vivo colon tissues suggest that the mucoid strain could have higher anti-inflammatory activity. Our findings provide relevant data on the function of Balat_1410 and reveal that the mucoid phenotype is able to alter some of the most relevant functional properties of the cells. 相似文献
1000.
Attila Balint TaeHyung Kim David Gallo Jose Renato Cussiol Francisco M Bastos de Oliveira Askar Yimit Jiongwen Ou Ryuichiro Nakato Alexey Gurevich Katsuhiko Shirahige Marcus B Smolka Zhaolei Zhang Grant W Brown 《The EMBO journal》2015,34(16):2182-2197
Obstructions to replication fork progression, referred to collectively as DNA replication stress, challenge genome stability. In Saccharomyces cerevisiae, cells lacking RTT107 or SLX4 show genome instability and sensitivity to DNA replication stress and are defective in the completion of DNA replication during recovery from replication stress. We demonstrate that Slx4 is recruited to chromatin behind stressed replication forks, in a region that is spatially distinct from that occupied by the replication machinery. Slx4 complex formation is nucleated by Mec1 phosphorylation of histone H2A, which is recognized by the constitutive Slx4 binding partner Rtt107. Slx4 is essential for recruiting the Mec1 activator Dpb11 behind stressed replication forks, and Slx4 complexes are important for full activity of Mec1. We propose that Slx4 complexes promote robust checkpoint signaling by Mec1 by stably recruiting Dpb11 within a discrete domain behind the replication fork, during DNA replication stress. 相似文献