Project description:Thymocytes were extracted from a pool of three 8-12 week old C57BL-6 female mice. Cells were separated from stroma by gently crushing the thymi in between 2 microslides. RNA from thymocytes was extracted using the Trizol reagent and protocol, and analysed using the Illumina HiSeq 2000.
Project description:Themis1, a recently described T-lineage specific protein, is essential for thymic positive and negative selection. Although Themis1 has been clearly identified as a component of the T cell antigen receptor (TCR) signalosome, its precise role in TCR signaling remains unclear. Here, we used quantitative proteomic and TCR signaling reporter mice to gain insight into Themis1 signaling function. Mass spectrometry analysis of the Themis1 interactome identified Grb2, SHP1 and Vav1 as the principal interacting partners of Themis1 in thymocytes. The dataset contains mass spectrometry results from the analysis of 6 different kind of AP-MS purifications (based on immunoprecipitation using a Themis1 antibody) starting from the following samples: - thymocytes from WT mice, non stimulated (noted WT NS) - thymocytes from WT mice, stimulated with pervanadate (noted WT P) - thymocytes from GRB2 +/- mice (with decreased expression of GRB2), non stimulated (noted GRB2 NS) - thymocytes from GRB2 +/- mice (with decreased expression of GRB2), stimulated with pervanadate (noted GRB2 P) - thymocytes from Themis1 -/- mice (knock-out for Themis1), non stimulated (noted KO NS) - thymocytes from Themis1 -/- mice (knock-out for Themis1), stimulated with pervanadate (noted KO P) Three biological replicates were prepared for these 6 different conditions (noted, 1,2,3), yielding 18 analyzed samples. Three technical nanoLC-MS runs were acquired for each sample (noted R1, R2, R3), leading to the 54 nanoLC-MS raw files contained in the dataset.
Project description:Sustained Ca2+ entry into CD4+CD8+ double-positive thymocytes is required for positive selection. We identified a voltage-gated Na+ channel (VGSC), essential for positive selection of CD4+ T cells. Pharmacological inhibition of VGSC activity inhibited sustained Ca2+ influx induced by positive-selecting ligands and in vitro positive selection of CD4+ but not CD8+ T cells. In vivo shRNA knockdown of Scn5a specifically inhibited positive selection of CD4+ T cells. Ectopic expression of VGSC in peripheral AND CD4+ T cells bestowed the ability to respond to a positively selecting ligand, directly demonstrating VGSC expression was responsible for increased sensitivity. Thus active VGSCs in thymocytes provides a mechanism by which a weak positive selecting signal can induce sustained Ca2+ signals required for CD4+ T cell development. Pre-selected AND DP thymocytes were stimulated with plate bound peptide-loaded I-Ek Ig dimers. Genes were differentially regulated by positive and negative selection signals. The goal of this study is to identify ion-channel related genes critical for thymic positive selection, given the sustained Ca2+ entry into double positive thymocytes is required for positive selection. Total RNA of pre-selected AND thymocytes stimulated with I-Ek Ig dimers loaded with the positively-selecting peptide gp250, the negatively-selecting agonist peptide MCC, or the non-selecting control peptide Hb were used for the transcriptional profiling analysis. We found 28 genes were differentially down-regulated by MCC stimulation but upregulated by gp250 stimulation. One of them, scn4b, was ion-channel related.
Project description:Sustained Ca2+ entry into CD4+CD8+ double-positive thymocytes is required for positive selection. We identified a voltage-gated Na+ channel (VGSC), essential for positive selection of CD4+ T cells. Pharmacological inhibition of VGSC activity inhibited sustained Ca2+ influx induced by positive-selecting ligands and in vitro positive selection of CD4+ but not CD8+ T cells. In vivo shRNA knockdown of Scn5a specifically inhibited positive selection of CD4+ T cells. Ectopic expression of VGSC in peripheral AND CD4+ T cells bestowed the ability to respond to a positively selecting ligand, directly demonstrating VGSC expression was responsible for increased sensitivity. Thus active VGSCs in thymocytes provides a mechanism by which a weak positive selecting signal can induce sustained Ca2+ signals required for CD4+ T cell development.
Project description:Comparative gene expression profiling of thymocytes at the DP, CD4 SP and CD8 SP stage derived from FoxN1-Gpr177 mice (FoxN1-Cre mediated deletion of (Exon3 of) Gpr177/Wtls) or C57Bl/6N mice as comparison. Objective was to test the influence of TEC-secreted Wnt ligands on the transcriptome of thymocytes at the respective developmental stages. Total RNA extracted from FACS-sorted primary mouse thymocytes. CD4/8 double positive (DP) thymocytes, CD4 single positive (CD4 SP) thymocytes and CD8 single positive (CD8 SP) thymocytes were FACS-sorted from conditional knock-out mice (FoxN1-Gpr177) and C57Bl/6N mice as comparison.
Project description:Review on the role of Bcl11b in thymus and periphery and impact on diseases RNA was extracted from DP thymocytes of bcl11bf/fCd4cre/tcra-/- and tcra-/- mice. Tcra-/- mice only have preselected DP thymocytes. Such mice were used to determine the role of Bcl11b before selection, considering the defective positive selection in bcl11bf/fcd4cre mice. RNA was isolated and submitted for library generation and microarray analysis to determine expression profile of bcl11b-/- preselected DP thymocytes.
Project description:The RNase III enzyme dicer is essential for the processing of microRNAs (miRNAs) and small interfering RNAs (siRNAs) from double-stranded RNA precursors. miRNAs and siRNAs regulate chromatin structure, gene transcription, mRNA stability and translation in a wide range of organisms. To provide a model system to explore the role of dicer-generated RNAs in the differentiation of mammalian cells in vivo, we have generated a conditional dicer allele. Deletion of dicer at an early stage of T cell development compromised the survival of αβ lineage cells, while the numbers of γδ-expressing thymocytes were not affected. In developing thymocytes, dicer was not required for the maintenance of transcriptional silencing at pericentromeric satellite sequences (constitutive heterochromatin), the maintenance of cytosine DNA methylation and X chromosome inactivation in female cells (facultative heterochromatin) and the stable shutdown of a developmentally regulated gene (developmentally regulated gene silencing). Most remarkably, given that one-third of mammalian mRNAs are putative miRNA targets, dicer appears to be dispensable for CD4/8 lineage commitment, a process where epigenetic regulation of lineage choice has been well documented. Thus, although dicer appears critical for the development of the early embryo, it may have limited impact on the implementation of lineage-specific gene expression programs. LckCre was used to delete a floxed Dicer1 allele from developing thymocytes (Cobb BS, Nesterova TB, Thompson E, Hertweck A, O'Connor E, Godwin J, Wilson CB, Brockdorff N, Fisher AG, Smale ST and Merkenschlager M. T cell lineage choice and differentiation in the absence of the RNAse III enzyme dicer. J. Exp. Med. 2005 201: 1367-1373). Thymocytes were stained for CD4 and CD8, and double-positive (DP) thymocytes were sorted by flow cytometry. Three biological replicates of Dicer lox/lox control samples and LckCre Dicer lox/lox KO samples were analysed.
Project description:Double positive thymocytes (CD4+CD8+CD3lo) were sorted from 3-4-week old mice from Ikf/f CD4-Cre+ or Ikf/f CD4-Cre- mice (2 mice per genotype) and their transcriptome analyzed.
Project description:T-cell-specific deletion of USP8 (USP8ffCD4Cre) revealed that USP8 is required for thymocyte transition to the CD4+ and CD8+ single positive (SP) stages. To evaluate underlying mechanisms, gene expression profilling was performed in CD4+CD8+ double pos thymocytes derived from control (USP8ff and USP8ffCD4Cre) mice.