Project description:Signal transducer and activator of transcription 4 (STAT4) and STAT6 are key factors in the specification of helper T cells; however, their direct roles in driving differentiation are not well understood. Using chromatin immunoprecipitation and massive parallel sequencing, we quantitated the full complement of STAT-bound genes, concurrently assessing global STAT-dependent epigenetic modifications and gene transcription using cells from cognate STAT-deficient mice. STAT4 and STAT6 each bound over 4000 genes with distinct binding motifs. Both played critical roles in maintaining chromatin configuration and transcription of a core subset of genes through the combination of different epigenetic patterns. Globally, STAT4 had a more dominant role in promoting active epigenetic marks, whereas STAT6 had a more prominent role in antagonizing repressive marks. Clusters of genes negatively regulated by STATs were also identified, highlighting previously unappreciated repressive roles. Therefore, STAT4 and STAT6 play wide regulatory roles in T helper specification. The roles of STAT proteins to shape T helper cell phenotype was investigated by comparing DNA binding profiles of STAT4 and STAT6 in Th1 and Th2 conditions. The functional outcome of STAT bindings was further evaluated by profiling histone epigenetic marks and gene expression changes between WT and STAT-deficient T cells in Th1 and Th2 conditions.
Project description:STAT6 is a major transcription factor driving the polarization of Th2 cells in response to IL-4. STAT6 is phosphorylated by Jak1 and Jak3 kinases at the IL-4 receptor, after which phosphorylated STAT6 forms a homodimer and translocates into the nucleus. There STAT6 binds to specific DNA sequences, regulating the transcription of its target genes. Here we have analyzed on a genome wide level the STAT6 binding sites, after 1h and 4h of IL-4 induction, in naive human CD4+ T cells. Keywords: SRA Altogether 5 samples from 1 biological replicate were analyzed. Activated and IL-4 treated samples were compared to only activated or untreated samples to identify unique STAT6 binding sites after IL-4 induction.
Project description:IL-4/STAT6-regulated transcriptome and proteome were compared in primary B cells isolated from wild-type and STAT6-deficient mice. B cells were purified from the spleen and stimulated in vitro with anti-CD40 and LPS or anti-IgM-F(ab)2 in the presence or absence of IL-4. Transcriptome analysis was performed with oligonucleotide microarrays. Global relative quantification of proteins was achieved by gel-enhanced label-free liquid chromatography/mass spectrometry (LC/MS). Hierarchical clustering and principal component analysis revealed that IL-4-induced changes of the transcriptome were almost completely dependent on STAT6. In contrast, the quantitative proteome analysis revealed that the expression of many IL-4-regulated proteins changes even in the absence of STAT6. The top 75 proteins with changes in abundance levels induced by IL-4 in a STAT6-dependent manner were also found to be regulated at the transcriptional level. Most of these proteins were not previously known to be regulated by STAT6 in B cells. We confirmed the MS-based quantitative proteome data by flow cytometric and Western blot analysis of selected proteins. This study provides a framework for further functional characterization of STAT6-regulated proteins in B cells that might be involved in germinal center formation and class switch recombination.
Project description:Although it is reported that mitochondria-localized nuclear transcription factors (TFs) regulate mitochondrial processes such as apoptosis and mitochondrial transcription/respiration, their functions and mechanisms of mitochondrial dynamics regulated by mitochondria-localized nuclear TFs are yet to be fully characterized. Here, we identify STAT6 as a mitochondrial protein that is localized in the outer membrane of mitochondria (OMM). In addition to regulating mitochondrial gene expression as a nuclear TF, STAT6 in OMM inhibits mitochondrial fusion by blocking MFN2 dimerization. This implies that STAT6 has dual role in overall mitochondrial process. Moreover, mitochondrial accumulation of STAT6 in response to these findings reveal that STAT6 is a new regulator of mitochondrial processes including mitochondrial biogenesis and fusion/fission mechanisms.
Project description:Purpose: To examine the expression profile of WT and Stat6 KO intestinal stem cells. Methods: We isolated Lgr5+ ISCs from the intestine tissue, and generated Stat6 KO ISCs through CRISPR/Cas9 approach. Results: Many genes are changed upon Stat6 KO cells. We pay special attention on Wnt/β-catenin signaling that is the most critical pathway in ISCs, and discovered Stat6 drove the expression of Wnt target genes. Conclusions: Stat6 crosstalks with Wnt signaling to drive ISC self-renewal.
Project description:STAT6 is a major transcription factor driving the polarization of Th2 cells in response to IL-4. STAT6 is phosphorylated by Jak1 and Jak3 kinases at the IL-4 receptor, after which phosphorylated STAT6 forms a homodimer and translocates into the nucleus. There STAT6 binds to specific DNA sequences, regulating the transcription of its target genes. Here we have analyzed on a genome wide level the STAT6 binding sites, after 1h and 4h of IL-4 induction, in naive human CD4+ T cells. Keywords: SRA
Project description:We report that Stat6-driven gene transcription regulates the transition from Tfh21 to Tfh4 cells, suppressing IL-21 production and promoting IL-4 secretion. We identified a cis-enhancer in the second intron of Il21 as a regulator of Tfh cell cytokine transition, via an effect of Stat6 on chromatin accessibility with repression of Il21 transcription. We conclude that Stat6 is necessary for coordinated regulation of IL-21 and IL-4 production by Tfh cells, leading to appropriate maturation of the germinal center B cell response.
Project description:Signal transducer and activator of transcription 4 (STAT4) and STAT6 are key factors in the specification of helper T cells; however, their direct roles in driving differentiation are not well understood. Using chromatin immunoprecipitation and massive parallel sequencing, we quantitated the full complement of STAT-bound genes, concurrently assessing global STAT-dependent epigenetic modifications and gene transcription using cells from cognate STAT-deficient mice. STAT4 and STAT6 each bound over 4000 genes with distinct binding motifs. Both played critical roles in maintaining chromatin configuration and transcription of a core subset of genes through the combination of different epigenetic patterns. Globally, STAT4 had a more dominant role in promoting active epigenetic marks, whereas STAT6 had a more prominent role in antagonizing repressive marks. Clusters of genes negatively regulated by STATs were also identified, highlighting previously unappreciated repressive roles. Therefore, STAT4 and STAT6 play wide regulatory roles in T helper specification.
Project description:Analysis of the transcriptional response of HEK293 or HEK293-STAT6 stable cell lines to poly(I:C) transfection. The hypothesis tested was that poly(I:C) transfection is capable of inducing the expression of STAT6-dependent antiviral genes. mRNA isolated from HEK293 or HEK293-STAT6 stable cell lines with control treatment or poly(I:C) transfection for 16 hours.
Project description:This SuperSeries is composed of the following subset Series: GSE22081: Discrete Roles of STAT4 and STAT6 Transcription Factors in Tuning Epigenetic Modifications and Transcription during Helper T Cell Differentiation (gene expression) GSE22104: Discrete Roles of STAT4 and STAT6 Transcription Factors in Tuning Epigenetic Modifications and Transcription during Helper T Cell Differentiation (ChIP-Seq) Refer to individual Series