Project description:Cellular binary fate decisions require the progeny to silence genes associated with the alternative fate. The major subsets of alpha:beta T cells have been extensively studied as a model system for fate decisions. While the transcription factor RUNX3 is required for the initiation of Cd4 silencing in CD8 T cell progenitors, it is not required to maintain the silencing of Cd4 and other helper T lineage genes. The other runt domain containing protein, RUNX1, silences Cd4 in an earlier T cell progenitor, but this silencing is reversed whereas the gene silencing after RUNX3 expression is not reverse. Therefore, we hypothesized that RUNX3 and not RUNX1 recruits other factors that maintains the silencing of helper T lineage genes in CD8 T cells. To this end, we performed a proteomics screen of RUNX1 and RUNX3 to determine candidate silencing factors.
Project description:The gene expression profile of peripheral Foxp3+ natural regulatory T cells isolated from Foxp3/EGFP bicistronic mice was compared to that of in vitro-induced regulatory T cells and to CD4+ conventional (Foxp3-) T cells. The role of the regulatory T cell transcription factor Foxp3 in shaping the transcriptosomes of natural and induced regulatory T cells was analyzed using mice expressing a mutant FOXP3-EGFP fusion protein (Foxp3deltaEGFP). We used gene expression microarrays to examine the transcriptional programs of natural and induced regulatory T cells and the function of Foxp3 in organizing the transcriptosomes of the respective cell type Experiment Overall Design: Conventional T cells and natural and induced regulatory T cells were derived from Foxp3/EGFP bicistronic mice and analyzed for their gene expression profile. Conventional T cells, regulatory T cell precursors (CD4+Foxp3deltaEGFP+) and induced regulatory T cell precursors (CD4+Foxp3deltaEGFP+) cells were deriv ed from Foxp3deltaEGFP mice
Project description:Gene expression profiling of CD4+CD25+Foxp3+ regulatory T cells and CD4+CD25-Foxp3- T cells in the course of Plasmodium yoelii infection of BALB/c mice
Project description:To describe the protein profile in hippocampus, colon and ileum tissue’ changing after the old faeces transplants, we adopted a quantitative label free proteomics approach.
Project description:Regulatory T (Treg) cells are important regulators of the immune system and have versatile functions for the homeostasis and repair of tissues. They express the forkhead box transcription factor Foxp3 as a lineage-defining protein. In mature Treg cells, the Foxp3 core promoter is unmethylated indicating that this area could harbor a transcription factor complex to initiate or repress gene expression, respectively. We used an unbiased method to identify Foxp3-promoter-binding transcription factors (TFs) by inverted chromatin immunoprecipitation (IP) followed by quantitative mass spectrometry. We identified several candidate factors which showed Foxp3-promoter suppressive capacity, one of which was T-cell factor 1 (Tcf1). Using viral overexpression and CRISPR/Cas knockout studies, we identified Tcf1 as a repressor of Foxp3 expression in primary conventional CD4 T cells (Tconv). In Tcf1-deficient animals, increased levels of Foxp3intermediateCD25negative T cells were identified in secondary lymphoid tissues, implicating that Tcf1 protects Foxp3-negative T cells from inadvertent Foxp3 expression.