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11.
Andoniou CE Andrews DM Manzur M Ricciardi-Castagnoli P Degli-Esposti MA 《The Journal of cell biology》2004,166(6):827-837
Infection with murine cytomegalovirus (MCMV) has contributed to understanding many aspects of human infection and, additionally, has provided important insight to understanding complex cellular responses. Dendritic cells (DCs) are a major target for MCMV infection. Here, we analyze the effects of MCMV infection on DC viability, and show that infected DCs become resistant to apoptosis induced by growth factor deprivation. The precise contribution of changes in the expression of Bcl-2 family proteins has been assessed and a new checkpoint in the apoptotic pathway identified. Despite their resistance to apoptosis, MCMV-infected DCs showed Bax to be tightly associated with mitochondria and, together with Bak, forming high molecular weight oligomers, changes normally associated with apoptotic cell death. Exposure of a constitutively occluded Bax NH2-terminal epitope was blocked after infection. These results suggest that MCMV has evolved a novel strategy for inhibiting apoptosis and provide evidence that apoptosis can be regulated after translocation, integration, and oligomerization of Bax at the mitochondrial membrane. 相似文献
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The role of alien fish (the centrarchid Micropterus salmoides) in lake food webs highlighted by stable isotope analysis 下载免费PDF全文
Maria Letizia Costantini Pasquale Carlino Edoardo Calizza Giulio Careddu Davide Cicala Simona Sporta Caputi Federico Fiorentino Loreto Rossi 《Freshwater Biology》2018,63(9):1130-1142
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When phylogenetic trees constructed from morphological and molecular evidence disagree (i.e. are incongruent) it has been
suggested that the differences are spurious or that the molecular results should be preferred a priori. Comparing trees can
increase confidence (congruence), or demonstrate that at least one tree is incorrect (incongruence). Statistical analyses
of 181 molecular and 49 morphological trees shows that incongruence is greater between than within the morphological and molecular
partitions, and this difference is significant for the molecular partition. Because the level of incongruence between a pair
of trees gives a minimum bound on how much error is present in the two trees, our results indicate that the level of error
may be underestimated by congruence within partitions. Thus comparisons between morphological and molecular trees are particularly
useful for detecting this incongruence (spurious or otherwise). Molecular trees have higher average congruence than morphological
trees, but the difference is not significant, and both within- and between-partition incongruence is much lower than expected
by chance alone. Our results suggest that both molecular and morphological trees are, in general, useful approximations of
a common underlying phylogeny and thus, when molecules and morphology clash, molecular phylogenies should not be considered
more reliable a priori. 相似文献
16.
Munton RP Tweedie-Cullen R Livingstone-Zatchej M Weinandy F Waidelich M Longo D Gehrig P Potthast F Rutishauser D Gerrits B Panse C Schlapbach R Mansuy IM 《Molecular & cellular proteomics : MCP》2007,6(2):283-293
Activity-dependent protein phosphorylation is a highly dynamic yet tightly regulated process essential for cellular signaling. Although recognized as critical for neuronal functions, the extent and stoichiometry of phosphorylation in brain cells remain undetermined. In this study, we resolved activity-dependent changes in phosphorylation stoichiometry at specific sites in distinct subcellular compartments of brain cells. Following highly sensitive phosphopeptide enrichment using immobilized metal affinity chromatography and mass spectrometry, we isolated and identified 974 unique phosphorylation sites on 499 proteins, many of which are novel. To further explore the significance of specific phosphorylation sites, we used isobaric peptide labels and determined the absolute quantity of both phosphorylated and non-phosphorylated peptides of candidate phosphoproteins and estimated phosphorylation stoichiometry. The analyses of phosphorylation dynamics using differentially stimulated synaptic terminal preparations revealed activity-dependent changes in phosphorylation stoichiometry of target proteins. Using this method, we were able to differentiate between distinct isoforms of Ca2+/calmodulin-dependent protein kinase (CaMKII) and identify a novel activity-regulated phosphorylation site on the glutamate receptor subunit GluR1. Together these data illustrate that mass spectrometry-based methods can be used to determine activity-dependent changes in phosphorylation stoichiometry on candidate phosphopeptides following large scale phosphoproteome analysis of brain tissue. 相似文献
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Marie Trussart Fran?ois Serra Davide Baù Ivan Junier Luís Serrano Marc A. Marti-Renom 《Nucleic acids research》2015,43(7):3465-3477
Restraint-based modeling of genomes has been recently explored with the advent of Chromosome Conformation Capture (3C-based) experiments. We previously developed a reconstruction method to resolve the 3D architecture of both prokaryotic and eukaryotic genomes using 3C-based data. These models were congruent with fluorescent imaging validation. However, the limits of such methods have not systematically been assessed. Here we propose the first evaluation of a mean-field restraint-based reconstruction of genomes by considering diverse chromosome architectures and different levels of data noise and structural variability. The results show that: first, current scoring functions for 3D reconstruction correlate with the accuracy of the models; second, reconstructed models are robust to noise but sensitive to structural variability; third, the local structure organization of genomes, such as Topologically Associating Domains, results in more accurate models; fourth, to a certain extent, the models capture the intrinsic structural variability in the input matrices and fifth, the accuracy of the models can be a priori predicted by analyzing the properties of the interaction matrices. In summary, our work provides a systematic analysis of the limitations of a mean-field restrain-based method, which could be taken into consideration in further development of methods as well as their applications. 相似文献
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Karen F Chambers Joanna F Pearson Davide Pellacani Naveed Aziz Miodrag Gužvić Christoph A Klein Shona H Lang 《Journal of biomedical science》2011,18(1):45
Background
Stromal signalling increases the lateral cell adhesions of prostate epithelial cells grown in 3D culture. The aim of this study was to use microarray analysis to identify significant epithelial signalling pathways and genes in this process. 相似文献20.
Bettina Maccagnani Francesca Giacomello Marco Fanti Davide Gobbin Stefano Maini Gino Angeli 《BioControl》2009,54(1):123-133
The efficiency of two pollinators, Apis mellifera L. (Hymenoptera: Apidae) and the mason bee Osmia cornuta (Latreille) (Hymenoptera: Megachilidae), as carriers of biocontrol agents (BCA) from flower to flower (secondary colonisation) was investigated on apple cv ‘Golden Delicious’. The BCA tested was Bacillus subtilis, strain BD170 (Biopro®) developed for the control of the ‘fire blight’ caused by Erwinia amylovora (Burril) Winslow et al. The two insect species were studied as secondary BCA carriers on apple plants in pots under net screened tunnels. Their behaviour and capacity to deposit the BCA in the most receptive flower parts were compared both by washing, diluting and plating the flower organs on a recovery medium and by means of PCR analyses based on a molecular marker. O. cornuta showed better performances with respect to A. mellifera. For the field trials, pollinators were introduced in four apple orchards. During apple’s flowering, the BD170 (100 g hl?l) was sprayed once in two fields, and twice in the others. The pollinators’ efficacy in carrying the BCA from sprayed flowers to the stigmas of newly opened ones at different times after the spray treatment was evaluated. The detection of the BCA was performed by PCR analysis. The percentages of positive PCR flower samples were higher in the internal treated areas of the fields with respect to the external untreated ones, but the high colonisation level found in the latter and in the flowers opened in both areas several days after the treatment(s) demonstrated that pollinators can play an important role as secondary carriers. 相似文献