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排序方式: 共有277条查询结果,搜索用时 490 毫秒
91.
92.
Sabry M. Youssef Iraida Amaya José M. López-Aranda Rafael Sesmero Victoriano Valpuesta Giorgio Casadoro Rosario Blanco-Portales Fernando Pliego-Alfaro Miguel A. Quesada José A. Mercado 《Molecular breeding : new strategies in plant improvement》2013,31(2):313-322
Strawberry is a soft fruit with a short postharvest shelf-life. The loss of fruit firmness during ripening is mainly due to the disassembly of parenchyma cell walls mediated by the expression of genes encoding enzymes acting on pectins, such as pectate lyase, or hemicellulose, e.g. endo-β-1,4-glucanase. To determine if the simultaneous down-regulation of FaplC and FaEG3 genes, encoding a pectate lyase and a endo-β-1,4-glucanase, respectively, exerted an additive effect on strawberry softening, transgenic plants expressing tandem antisense sequences of both genes under the control of the constitutive promoter CaMV35S were generated. Fifteen independent transgenic lines were obtained and fruit yields and several quality parameters of transgenic ripe fruit were recorded during two consecutive years. Fruit yield was reduced in most of the lines, especially in the first evaluation period, and five out of 15 lines (33 %) did not set fruit. The expression of FaplC and FaEG3 genes was measured in ripe fruits from six selected lines showing the highest fruit yields. All selected lines showed a high level of FaplC gene silencing, ranging from 97 to 71 %; however, FaEG3 gene expression was only significantly down-regulated in two lines. Fruit colour and soluble solids contents were similar in control and transgenic ripe fruits, while fruit weight was slightly lower than control in some of the lines. In all lines, transgenic fruits were significantly firmer than control, with an increase in firmness ranging from 19 to 32 %. The reduction of fruit softening in transgenic fruits was not correlated with the suppression of FaEG3 gene expression, and lines with the highest simultaneous down-regulation of FaplC and FaEG3 showed similar fruit firmness to lines where only FaplC was suppressed. These results indicate that pectate lyase and endo-β-1,4-glucanase do not act in an additive or synergistic way during strawberry softening, and question the role of glucanases in this process. 相似文献
93.
Yasmín Zorrilla-Fontanesi Amalia Cabeza Ana M. Torres Miguel A. Botella Victoriano Valpuesta Amparo Monfort José F. Sánchez-Sevilla Iraida Amaya 《Molecular breeding : new strategies in plant improvement》2011,27(2):137-156
Cultivated strawberry (Fragaria × ananassa) together with other economically important genera such as Rosa (roses) and Rubus (raspberry and blackberry) belongs to the subfamily Rosoideae. There is increasing interest in the development of transferable
markers to allow genome comparisons within the Rosaceae family. In this report, 122 new genic microsatellite (SSR) markers
have been developed from cultivated strawberry and its diploid ancestor Fragaria vesca. More than 77% of the sequences from which the markers were developed show significant homology to known or predicted proteins
and more than 92% were polymorphic among strawberry cultivars, representing valuable markers in transcribed regions of the
genome. Sixty-three SSRs were polymorphic in the diploid Fragaria reference population and were bin-mapped together with another five previously reported but unmapped markers. In total, 72
loci were distributed across the seven linkage groups. In addition, the transferability of 174 Fragaria SSRs to the related Rosa and Rubus genera was investigated, ranging from 28.7% for genic-SSRs in rose to 16.1% for genomic-SSRs in raspberry. Among these markers,
33 and 16 were both localized in the diploid Fragaria reference map and cross-amplified in rose and raspberry, respectively. These results indicate that transferability of SSRs
across the Rosoideae subfamily is limited. However, we have identified a set of Fragaria markers, polymorphic in the diploid reference population, which cross-amplified in both Rosa and Rubus, which represents a valuable tool for comparative mapping and genetic diversity analyses within the Rosoideae subfamily. 相似文献
94.
The technology platforms for proteome analysis have advanced considerably over the last few years. Driven by these advancements in technology, the number of studies on the analysis of the proteome/peptidome, with the aim of defining clinically relevant biomarkers, has substantially risen. Urine has become an increasingly relevant target for clinically oriented proteome analysis; the first clinical trials based on urinary proteomics have been initiated, and studies including several hundred patients have been published. In this article, we summarize the relevant technical aspects in biomarkers discovery and the course from biomarker discovery or 'potential' biomarkers to those that have been validated and are clinically important. We discuss experimental design based on the statistics calculated to produce a clinically important end point. We present several examples of proteomic studies that have defined urinary biomarkers for clinical applications, focusing on capillary electrophoresis coupled to mass spectrometry as a technology. Finally, current challenges and considerations for future studies will be discussed. 相似文献
95.
Anne von Thun Christian Preisinger Oliver Rath Juliane P. Schwarz Chris Ward Naser Monsefi Javier Rodríguez Amaya Garcia-Munoz Marc Birtwistle Willy Bienvenut Kurt I. Anderson Walter Kolch Alex von Kriegsheim 《Molecular and cellular biology》2013,33(22):4526-4537
In certain Ras mutant cell lines, the inhibition of extracellular signal-regulated kinase (ERK) signaling increases RhoA activity and inhibits cell motility, which was attributed to a decrease in Fra-1 levels. Here we report a Fra-1-independent augmentation of RhoA signaling during short-term inhibition of ERK signaling. Using mass spectrometry-based proteomics, we identified guanine exchange factor H1 (GEF-H1) as mediating this effect. ERK binds to the Rho exchange factor GEF-H1 and phosphorylates it on S959, causing inhibition of GEF-H1 activity and a consequent decrease in RhoA activity. Knockdown experiments and expression of a nonphosphorylatable S959A GEF-H1 mutant showed that this site is crucial in regulating cell motility and invasiveness. Thus, we identified GEF-H1 as a critical ERK effector that regulates motility, cell morphology, and invasiveness. 相似文献
96.
Cristina Castillejo Veronika Waurich Henning Wagner Rubn Ramos Nicols Oiza Pilar Muoz Juan C. Trivio Julie Caruana Zhongchi Liu Nicols Cobo Michael A. Hardigan Steven J. Knapp Jos G. Vallarino Sonia Osorio Carmen Martín-Pizarro David Pos Tuomas Toivainen Timo Hytnen Youngjae Oh Christopher R. Barbey Vance M. Whitaker Seonghee Lee Klaus Olbricht Jos F. Snchez-Sevilla Iraida Amaya 《The Plant cell》2020,32(12):3723
97.
Jos G. Vallarino Catharina Merchante Jos F. Snchez‐Sevilla María Angels de Luis Balaguer Delphine M. Pott María T. Ariza Ana Casaal David Pos Amalia Vioque Iraida Amaya Lothar Willmitzer Roberto Solano Rosangela Sozzani Alisdair R. Fernie Miguel A. Botella James J. Giovannoni Victoriano Valpuesta Sonia Osorio 《Plant biotechnology journal》2020,18(4):929-943
98.
Amaya L. Bustinduy José C. Sousa-Figueiredo Moses Adriko Martha Betson Alan Fenwick Narcis Kabatereine J. Russell Stothard 《PLoS neglected tropical diseases》2013,7(11)
Background
Calprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB) is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ).Methods
216 children (ages 3–9 years old) from Buliisa District in Lake Albert, Uganda were examined and treated with PZQ at baseline in October 2012 with 211 of them re-examined 24 days later for S. mansoni and other soil transmitted helminths (STH). POC calprotectin and FOB assays were performed at both time points on a subset of children. Associations between the test results and infection were analysed by logistic regression.Results
Fecal calprotectin concentrations of 150–300 µg/g were associated with S. mansoni egg patent infection both at baseline and follow up (OR: 12.5 P = 0.05; OR: 6.8 P = 0.02). FOB had a very strong association with baseline anemia (OR: 9.2 P = 0.03) and medium and high egg intensity schistosomiasis at follow up (OR: 6.6 P = 0.03; OR: 51.3 P = 0.003). Both tests were strongly associated with heavy intensity S. mansoni infections. There was a significant decrease in FOB and calprotectin test positivity after PZQ treatment in those children who had egg patent schistosomiasis at baseline.Conclusions
Both FOB and calprotectin rapid assays were found to correlate positively and strongly with egg patent S. mansoni infection with a positive ameloriation response after PZQ treatment indicative of short term reversion of morbidity. Both tests were appropriate for use in the field with excellent operational performance and reliability. Due to its lower-cost which makes its scale-up of use affordable, FOB could be immediately adopted as a monitoring tool for PC campaigns for efficacy evaluation before and after treatment. 相似文献99.
The comet assay is now the method of choice for measuring most kinds of DNA damage in cells. However, due to the lack of a standardised protocol inter-laboratory comparisons are of limited value. The aim of this paper is to demonstrate how small changes in comet-assay variables may significantly affect the results. We examined the effect of varying agarose concentrations, alkaline unwinding time, electrophoresis time, voltage and current, by use of two cell types, viz. human peripheral blood lymphocytes and the lymphoblastoid cell line TK-6. All these variables have marked effects on assay performance and, therefore, on the determination of DNA damage. Here we identify factors of particular importance. 相似文献
100.
Elwy M. Soliman Michele Angela Rodrigues Dawidson Assis Gomes Nina Sheung Jin Yu Maria Jimina Amaya Michael H. Nathanson Jonathan A. Dranoff 《Cell calcium》2009,45(3):284-292
Hepatic stellate cells (HSC) are important mediators of liver fibrosis. Hormones linked to downstream intracellular Ca2+ signals upregulate HSC proliferation, but the mechanisms by which this occurs are unknown. Nuclear and cytosolic Ca2+ signals may have distinct effects on cell proliferation, so we expressed plasmid and adenoviral constructs containing the Ca2+ chelator parvalbumin (PV) linked to either a nuclear localization sequence (NLS) or a nuclear export sequence (NES) to block Ca2+ signals in distinct compartments within LX-2 immortalized human HSC and primary rat HSC. PV-NLS and PV-NES constructs each targeted to the appropriate intracellular compartment and blocked Ca2+ signals only within that compartment. PV-NLS and PV-NES constructs inhibited HSC growth. Furthermore, blockade of nuclear or cytosolic Ca2+ signals arrested growth at the G2/mitosis (G2/M) cell-cycle interface and prevented the onset of mitosis. Blockade of nuclear or cytosolic Ca2+ signals downregulated phosphorylation of the G2/M checkpoint phosphatase Cdc25C. Inhibition of calmodulin kinase II (CaMK II) had identical effects on LX-2 growth and Cdc25C phosphorylation. We propose that nuclear and cytosolic Ca2+ are critical signals that regulate HSC growth at the G2/M checkpoint via CaMK II-mediated regulation of Cdc25C phosphorylation. These data provide a new logical target for pharmacological therapy directed against progression of liver fibrosis. 相似文献