Search results for "techniques"
showing 10 items of 4426 documents
SANS (USH1G) regulates pre-mRNA splicing by mediating the intra-nuclear transfer of tri-snRNP complexes
2021
Abstract Splicing is catalyzed by the spliceosome, a compositionally dynamic complex assembled stepwise on pre-mRNA. We reveal links between splicing machinery components and the intrinsically disordered ciliopathy protein SANS. Pathogenic mutations in SANS/USH1G lead to Usher syndrome—the most common cause of deaf-blindness. Previously, SANS was shown to function only in the cytosol and primary cilia. Here, we have uncovered molecular links between SANS and pre-mRNA splicing catalyzed by the spliceosome in the nucleus. We show that SANS is found in Cajal bodies and nuclear speckles, where it interacts with components of spliceosomal sub-complexes such as SF3B1 and the large splicing cofact…
In Vitro Phenotypic, Genomic and Proteomic Characterization of a Cytokine-Resistant Murine β-TC3 Cell Line
2012
Type 1 diabetes mellitus (T1DM) is caused by the selective destruction of insulin-producing β-cells. This process is mediated by cells of the immune system through release of nitric oxide, free radicals and pro-inflammatory cytokines, which induce a complex network of intracellular signalling cascades, eventually affecting the expression of genes involved in β-cell survival. The aim of our study was to investigate possible mechanisms of resistance to cytokine-induced β-cell death. To this purpose, we created a cytokine-resistant β-cell line (β-TC3R) by chronically treating the β-TC3 murine insulinoma cell line with IL-1β + IFN-γ. β-TC3R cells exhibited higher proliferation rate and resistan…
Bioassays to monitor taspase1 function for the identification of pharmacogenetic inhibitors
2011
Background Threonine Aspartase 1 (Taspase1) mediates cleavage of the mixed lineage leukemia (MLL) protein and leukemia provoking MLL-fusions. In contrast to other proteases, the understanding of Taspase1's (patho)biological relevance and function is limited, since neither small molecule inhibitors nor cell based functional assays for Taspase1 are currently available. Methodology/Findings Efficient cell-based assays to probe Taspase1 function in vivo are presented here. These are composed of glutathione S-transferase, autofluorescent protein variants, Taspase1 cleavage sites and rational combinations of nuclear import and export signals. The biosensors localize predominantly to the cytoplasm…
Missing value imputation in proximity extension assay-based targeted proteomics data
2020
Targeted proteomics utilizing antibody-based proximity extension assays provides sensitive and highly specific quantifications of plasma protein levels. Multivariate analysis of this data is hampered by frequent missing values (random or left censored), calling for imputation approaches. While appropriate missing-value imputation methods exist, benchmarks of their performance in targeted proteomics data are lacking. Here, we assessed the performance of two methods for imputation of values missing completely at random, the previously top-benchmarked ‘missForest’ and the recently published ‘GSimp’ method. Evaluation was accomplished by comparing imputed with remeasured relative concentrations…
Multiple changes induced by fibroblasts on breast cancer cells.
2010
It is now widely recognised that the cross-talk between cancer and stromal cells may play a crucial role in cancer progression. However little is known about the complex underlying molecular mechanisms that occur within the tumor microenvironment. Fibroblasts are the major stromal cells with multiple roles, especially towards both the extracellular matrix and the neighbouring cell population, including neoplastic cells. Consequently, proteomic analyses would provide a wider resource for a better understanding of the potential modulating effects exerted by fibroblasts on cancer cells. In this report we describe the effects of fibroblast stimulation on the breast cancer cell line (8701-BC) pr…
Building high-quality assay libraries for targeted analysis of SWATH MS data
2015
Targeted proteomics by selected/multiple reaction monitoring (S/MRM) or, on a larger scale, by SWATH (sequential window acquisition of all theoretical spectra) MS (mass spectrometry) typically relies on spectral reference libraries for peptide identification. Quality and coverage of these libraries are therefore of crucial importance for the performance of the methods. Here we present a detailed protocol that has been successfully used to build high-quality, extensive reference libraries supporting targeted proteomics by SWATH MS. We describe each step of the process, including data acquisition by discovery proteomics, assertion of peptide-spectrum matches (PSMs), generation of consensus sp…
Multi-laboratory experiment PME11 for the standardization of phosphoproteome analysis
2022
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Exploration of the Sea Urchin Coelomic Fluid via Combinatorial Peptide Ligand Libraries
2012
The urchin Paracentrotus lividus has been characterized via previous capture and enhancement of low-abundance proteins with combinatorial peptide ligand libraries (CPLL, ProteoMiner). Whereas in the control only 26 unique gene products could be identified, 82 species could be detected after CPLL treatment. Due to the overwhelming presence of two major proteins-the toposome (a highly glycosylated, modified calcium-binding, iron-less transferrin) and the major yolk proteins, belonging to the class of cell adhesion proteins-which constituted about 70% of the proteome of this biological fluid and strongly interfered with the capture of the minority proteome, no additional proteins could be dete…
Real-time detection of BRAF V600E mutation from archival hairy cell leukemia FFPE tissue by nanopore sequencing
2018
The MinION is a miniaturized high-throughput next generation sequencing platform of novel conception. The use of nucleic acids derived from formalin-fixed paraffin-embedded samples is highly desirable, but their adoption for molecular assays is hurdled by the high degree of fragmentation and by the chemical-induced mutations stemming from the fixation protocols. In order to investigate the suitability of MinION sequencing on formalin-fixed paraffin-embedded samples, the presence and frequency of BRAF c.1799T > A mutation was investigated in two archival tissue specimens of Hairy cell leukemia and Hairy cell leukemia Variant. Despite the poor quality of the starting DNA, BRAF mutation was su…
FVIII production by human lung microvascular endothelial cells
2006
While extrahepatic factor VIII (FVIII) synthesis suffices for hemostasis, the extrahepatic production sites are not well defined. We therefore investigated the ability of the human lungs to produce FVIII. Lungs from heart-beating donors who were declined for transplantation were perfused and ventilated in an isolated reperfusion model for 2 hours. A progressive accumulation of FVIII and von Willebrand factor (VWF) was recorded in the perfusion medium in 3 of 4 experiments. By contrast, factor V, fibrinogen, and immunoglobulin G (IgG) levels remained constant during the perfusion period, indicating that the accumulation of FVIII and VWF was not due to diffusion from the intercellular medium …