Project description:Comparison of Clostridium difficile transcriptome of strain CD630E grown for 10 hours in PY (supplemented with mild concentration of cysteine) versus PYC (PY supplemented with 10 mM of cysteine). Experimental procedure was designed to investigate the influence of cysteine on toxins production and the regulatory network involved. two-conditions experiments, excess of cysteine vs mild concentration of cysteine, 4 biological replicates for each condition Description of the supplementary files: Main - Short description of the experiment Result_all - All significative genes Result_Gold* - High quality significative gene Result_Silver** - Medium quality significative gene All_Raw_data - All genes results significative and non significative Design_Genes-OUT - Genes not present in the platform Design_Genes-Oligos - Number of oligos design per gene * Gold : Nbr significative oligos = Nbr oligos designed for this gene ** Silver : Nbr significative oligos = Nbr oligos designed for this gene -1
Project description:Non cancerous PNT1A and cancerous PC3 prostate cells were treated with a novel isothiocyanate (PY-ITC) and compared to sulforaphane (SF), an isothiocyanate (ITC) derived from broccoli. Treatments with these ITCs were performed in the presence and absence on the PI3K inhibitor LY294002.
Project description:Phosphotyrosine (pY) enrichment is critical for expanding fundamental and clinical understanding of cellular signaling by mass spectrometry-based proteomics. However, current pY enrichment methods exhibit a high cost per sample and limited reproducibility due to expensive affinity reagents and manual processing. We present rapid-robotic phosphotyrosine proteomics (R2-pY), which uses a magnetic particle processor and pY superbinders or antibodies. R2-pY can handle up to 96 samples in parallel, requires 2 days to go from cell lysate to mass spectrometry injections, and results in global proteomic, phosphoproteomic and tyrosine-specific phosphoproteomic samples. We benchmark the method on HeLa cells stimulated with pervanadate and serum and report over 4000 unique pY sites from 1 mg of peptide input, strong reproducibility between replicates, and phosphopeptide enrichment efficiencies above 99%. R2-pY extends our previously reported R2-P2 proteomic and global phosphoproteomic sample preparation framework, opening the door to large-scale studies of pY signaling in concert with global proteome and phosphoproteome profiling.
Project description:Protein tyrosine phosphorylation is an important mechanism that regulates cytoskeleton reorganization and cell spreading of migratory cells. A number of cytoskeletal proteins are known to be tyrosine phosphorylated (pY) in different cellular processes. However, the profile of pY proteins during different stages of cell spreading has not been available.
Project description:Analysis of tyrosine kinase signaling is critical for the development of targeted cancer therapy. Currently, immunoprecipitation (IP) of phosphotyrosine (pY) peptides prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) is used to profile kinase substrates. A typical protocol requests 10 mg of total protein from ~108 cells or 50-100 mg of tissue. Large sample requirements can be cost prohibitive or not feasible for certain experiments. Sample multiplexing in chemical labeling reduces the protein amount required for each sample, and newer approaches use a material-rich reference channel as a calibrator to trigger detection and quantification for even smaller samples. Here, we demonstrate that the tandem mass tag (TMT) calibrator approach reduces the sample input for pY profiling 10-fold (to ~1 mg total protein per sample from 107 cells grown in 1 plate), while maintaining the depth of pY proteome sampling and the biological content of the experiment. This strategy opens more opportunities for pY profiling of large sample cohorts and samples with limited protein quantity such as immune cells, xenograft models, and human tumors.
Project description:Analysis of tyrosine kinase signaling is critical for the development of targeted cancer therapy. Currently, immunoprecipitation (IP) of phosphotyrosine (pY) peptides prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) is used to profile kinase substrates. A typical protocol requests 10 mg of total protein from ~108 cells or 50-100 mg of tissue. Large sample requirements can be cost prohibitive or not feasible for certain experiments. Sample multiplexing in chemical labeling reduces the protein amount required for each sample, and newer approaches use a material-rich reference channel as a calibrator to trigger detection and quantification for smaller samples. Here, we demonstrate that the tandem mass tag (TMT) calibrator approach reduces the sample input for pY profiling 10-fold (to ~1 mg total protein per sample from 107 cells grown in one plate), while maintaining the depth of pY proteome sampling and the biological content of the experiment. This strategy opens more opportunities for pY profiling of large sample cohorts and samples with limited protein quantity such as immune cells, xenograft models, and human tumors.
Project description:Transcriptionnal profiling of C. difficile R20291 strain : a wild type strain, a fliC mutant and a fliC mutant complemented after 14h of growth in PY and a wild type strain and a fliC mutant after 14h of mouse infection in Vivo two-conditions experiments, R20291 strain : a wild type strain, a fliC mutant and a fliC mutant complemented in Vitro and a wild type strain and a fliC mutant in Vivo, 4 biological replicates for each condition, in an direct design.
Project description:Background Regulation of transcription is essential for any organism and Rhizobium etli (a multi-replicon, nitrogen-fixing symbiotic bacterium) is no exception. This bacterium is commonly found in the rhizosphere (free-living) or inside of root-nodules of the common bean (Phaseolus vulgaris) in a symbiotic relationship. Abiotic stresses, such as high soil temperatures and salinity, compromise the genetic stability of R. etli and therefore its symbiotic interaction with P. vulgaris. However, it is still unclear which genes are up- or down-regulated to cope with these stress conditions. The aim of this study was to identify the genes and non-coding RNAs (ncRNAs) that are differentially expressed under heat and saline shock, as well as the promoter regions of the up-regulated loci. Results Analysing the heat and saline shock responses of R. etli CE3 through RNA-Seq, we identified 756 and 392 differentially expressed genes, respectively, and 106 were up-regulated under both conditions. Notably, the set of genes over-expressed under either condition was preferentially encoded on plasmids, although this observation was more significant for the heat shock response. In contrast, during either saline shock or heat shock, the down-regulated genes were principally chromosomally encoded. Our functional analysis shows that genes encoding chaperone proteins were up-regulated during the heat shock response, whereas genes involved in the metabolism of compatible solutes were up-regulated following saline shock. Furthermore, we identified thirteen and nine ncRNAs that were differentially expressed under heat and saline shock, respectively, as well as eleven ncRNAs that had not been previously identified. Finally, using an in silico analysis, we studied the promoter motifs in all of the non-coding regions associated with the genes and ncRNAs up-regulated under both conditions. Conclusions Our data suggest that the replicon contribution is different for different stress responses and that the heat shock response is more complex than the saline shock response. In general, this work exemplifies how strategies that not only consider differentially regulated genes but also regulatory elements of the stress response provide a more comprehensive view of bacterial gene regulation. mRNA of nine independent cultures of wild type strain Rhizobium etli CE3 were sequenced using Illumina GAIIx. Our parameters were: all cultures were taken from exponential phase, at 30M-BM-0C for 30min in control condition; 42M-BM-0C for 30min for the culture subject to heat -shock, and 30min at 30M-BM-0C in supplementary PY medium with 80mM NaCl for the saline shock condition.
Project description:The purpose of this experiment is to determine the phosphorylation ratio of pT vs pY ERK present in ERK phosphorylation reaction by activated MEK E203K or MEK WildType. Aliquots were collected at 3 minutes 15 seconds, the time at which the mono-phosphorylated ERK is at its maximal. To determine the ratio between pT and pY ERK, synthetic AQUA peptides corresponding to the pY- and the pT-phosphorylated ERK were spiked into the sample. The two peptides have identical mass but they can be umabiguguously distinguished by their elution times and fragmentation spectra.
Project description:Epigenomic profiling by ChIP-seq is a prevailing methodology used to investigate chromatin-based regulation in biological systems, such as human disease, yet the lack of an empirical methodology to normalize amongst experiments has limited the usefulness of this technique. Here we describe a “spike-in” normalization method that allows the quantitative comparison of histone modification status across cell populations using defined quantities of a reference epigenome. We demonstrate the utility of this method in measuring epigenomic changes following chemical perturbations and show how control normalization of ChIP-seq experiments enables discovery of disease-relevant changes in histone modification occupancy.