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81.
Eritja R Aviñó A de la Torre BG Fitzmaurice D Ongaro A Stanca SE DiSalvo A Maninng B Iacopino D 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1605-1609
Several linear and branched DNA structures from 80-200 nm with a biotine molecule in the middle have been prepared. These structures have been decorated by addition of positively charged gold nanoparticles carrying 4-(dimethylamino)pyridine ligands. Streptavidin binds to the central biotine molecule introducing a 20 nm gap in the structure in which a biotinylated nanoparticle can be introduced. The simplest structure (80 nm, linear) is formed by 4 oligonucleotides. By changing some of these components changes on length, shape, and recognition system easily can be introduced. 相似文献
82.
MOTIVATION: Increasing complexity of cell signaling network maps requires sophisticated visualization technologies. Simple web-based visualization tools can allow for improved data presentation and collaboration. Researchers studying cell signaling would benefit from having the ability to embed dynamic cell signaling maps in web pages. SUMMARY: AVIS is a Google gadget compatible web-based viewer of interactive cell signaling networks. AVIS is an implementation of AJAX (Asynchronous JavaScript with XML) with the usage of the libraries GraphViz, ImageMagic (PerlMagic) and overLib. AVIS provides web-based visualization of text-based signaling networks with dynamical zooming, panning and linking capabilities. AVIS is a cross-platform web-based tool that can be used to visualize network maps as embedded objects in any web page. AVIS was implemented for visualization of PathwayGenerator, a tool that displays over 4000 automatically generated mammalian cell signaling maps; NodeNeighborhood a tool to visualize first and second interacting neighbors of yeast and mammalian proteins; and for Genes2Networks, a tool to connect lists of genes and protein using background protein interaction networks. AVAILABILITY: A demo page of AVIS and links to applications and distributions can be found at http://actin.pharm.mssm.edu/AVIS2. Detailed instructions for using and configuring AVIS can be found in the user manual at http://actin.pharm.mssm.edu/AVIS2/manual.pdf. 相似文献
83.
84.
Functional atlas of the integrin adhesome 总被引:12,自引:0,他引:12
A detailed depiction of the 'integrin adhesome', consisting of a complex network of 156 components linked together and modified by 690 interactions is presented. Different views of the network reveal several functional 'subnets' that are involved in switching on or off many of the molecular interactions within the network, consequently affecting cell adhesion, migration and cytoskeletal organization. Examination of the adhesome network motifs reveals a relatively small number of key motifs, dominated by three-component complexes in which a scaffolding molecule recruits both a signalling molecule and its downstream target. We discuss the role of the different network modules in regulating the structural and signalling functions of cell-matrix adhesions. 相似文献
85.
Landscape pattern metrics are widely used for predicting habitat and species diversity. However, the relationship between landscape pattern and species diversity is typically measured at a single spatial scale, even though both landscape pattern, and species occurrence and community composition are scale‐dependent. While the effects of scale on landscape pattern are well documented, the effects of scale on the relationships between spatial pattern and species richness and composition are not well known. Here, our main goal was to quantify the effects of cartographic scale (spatial resolution and extent) on the relationships between spatial pattern and avian richness and community structure in a mosaic of grassland, woodland, and savanna in central Wisconsin. Our secondary goal was to evaluate the effectiveness of a newly developed tool for spatial pattern analysis, multiscale contextual spatial pattern analysis (MCSPA), compared to existing landscape metrics. Landscape metrics and avian species richness had quadratic, exponential, or logarithmic relationships, and these patterns were generally consistent across two spatial resolutions and six spatial extents. However, the magnitude of the relationships was affected by both resolution and extent. At the finer resolution (10‐m), edge density was consistently the best predictor of species richness, followed by an MCSPA metric that measures the standard deviation of woody cover across extents. At the coarser resolution (30‐m), NDVI was the best predictor of species richness by far, regardless of spatial extent. Another MCSPA metric that denotes the average woody cover across extents, together with percent of woody cover, were always the best predictors of variation in avian community structure. Spatial resolution and extent had varying effects on the relationships between spatial pattern and avian community structure. We therefore conclude that cartographic scale not only affects measures of landscape pattern per se, but also the relationships among spatial pattern, species richness, and community structure, often in complex ways, which reduces the efficacy of landscape metrics for predicting the richness and diversity of organisms. 相似文献
86.
A prominent feature of ionotropic glutamate receptors from the AMPA and kainate subtypes is their profound desensitization in response to glutamate-a process thought to protect the neuron from overexcitation. In AMPA receptors, it is well established that desensitization results from rearrangements of the interface formed between agonist-binding domains of adjacent subunits; however, it is unclear how this mechanism applies to kainate receptors. Here we show that stabilization of the binding domain dimer by the generation of intermolecular disulfide bonds apparently blocked desensitization of the kainate receptor GluR6. This result establishes a common desensitization mechanism in both AMPA and kainate receptors. Surprisingly, however, surface expression of these nondesensitizing mutants was drastically reduced and did not depend on channel activity. Therefore, in addition to its role at the synapse, we now propose an intracellular role for desensitization in controlling maturation and trafficking of glutamate receptors. 相似文献
87.
The vertical inflorescences of the Mediterranean annual Salvia viridis carry many small, colorful flowers, and are frequently terminated by a conspicuous tuft of colorful leaves ('flag') that attracts insect visitors. Insects may use the flags as indicators of food rewards in the inflorescences below, as long-distance cues for locating and choosing flowering patches, or both. Clipping of all flags from patches of inflorescences in the field reduced the number of arriving insects, but not the total number of inflorescences and flowers visited by them. The number of flowers visited per inflorescence increased with inflorescence size, and inflorescence and flower visits rates significantly increased with patch size. Six percent of the plants in the study population did not develop any flag during blooming, yet suffered no reduction in seed set as compared to flag-bearing neighboring individuals. Removal of flags from all inflorescences in a patch reduced seed set in comparison with untreated controls, while flag clipping from ten randomly selected inflorescences in a patch did not decrease seed production. These results suggest that flags signal long-distance information to potential pollinators (possibly indicating patch location or size), while flower-related cues may indicate inflorescence quality.
Plants that do not develop flags probably benefit from the flag signals displayed by their neighbors, without bearing the costs of signal production. Greenhouse-grown S. viridis plants allocated a low proportion of their biomass to flags. Plants grown under water stress did not reduce biomass allocation to flags as compared to irrigated controls. Water loss rates of picked flags were lower than those of picked leaves. These findings suggest that the expenses of flag production and maintenance are modest, reducing the selective advantage of individuals that do not carry flags. We discuss additional potential evolutionary mechanisms that may select for flag production. 相似文献
Plants that do not develop flags probably benefit from the flag signals displayed by their neighbors, without bearing the costs of signal production. Greenhouse-grown S. viridis plants allocated a low proportion of their biomass to flags. Plants grown under water stress did not reduce biomass allocation to flags as compared to irrigated controls. Water loss rates of picked flags were lower than those of picked leaves. These findings suggest that the expenses of flag production and maintenance are modest, reducing the selective advantage of individuals that do not carry flags. We discuss additional potential evolutionary mechanisms that may select for flag production. 相似文献
88.
89.
Monitoring of tumor response to chemotherapy in vivo by a novel small-molecule detector of apoptosis 总被引:1,自引:0,他引:1
Hagit Grimberg Galit Levin Anat Shirvan Avi Cohen Merav Yogev-Falach Ayelet Reshef Ilan Ziv 《Apoptosis : an international journal on programmed cell death》2009,14(3):257-267
Utilization of molecular imaging of apoptosis for clinical monitoring of tumor response to anti-cancer treatments in vivo
is highly desirable. To address this need, we now present ML-9 (butyl-2-methyl-malonic acid; MW = 173), a rationally designed
small-molecule detector of apoptosis, based on a novel alkyl-malonate motif. In proof-of-concept studies, induction of apoptosis
in tumor cells by various triggers both in vitro and in vivo was associated with marked uptake of 3H-ML-9 administered in vivo, in correlation with the apoptotic hallmarks of DNA fragmentation, caspase-3 activation and membrane
phospholipid scrambling, and with correlative tumor regression. ML-9 uptake following chemotherapy was tumor-specific, with
rapid clearance of the tracer from the blood and other non-target organs. Excess of non-labeled “cold” compound competitively
blocked ML-9 tumor uptake, thus demonstrating the specificity of ML-9 binding. ML-9 may therefore serve as a platform for
a novel class of small-molecule imaging agents for apoptosis, useful for assessment of tumor responsiveness to treatment.
H. Grimberg, G. Levin and A. Shirvan contributed equally to this article. 相似文献
90.
Ehud Katz Mario Fon Richard A Eigenheer Brett S Phinney Joseph N Fass Dawei Lin Avi Sadka Eduardo Blumwald 《Proteome science》2010,8(1):1-19