Project description:STAT4 dynamically interacts with the genomic landscape and functions in modulating chromatin accessibility to influence gene expression. We aimed to evaluate the impact of STAT4 on chromatin accessibility of colonic lamina propria ILC1s. To address this aim, we sorted ILC1s from the colonic LP of unmanipulated C57BL/6 and STAT4-/- mice and performed the assay for transposase-accessible chromatin using sequencing (ATAC-seq).
Project description:The purpose of this study is to compare transcriptional profiles of WT and STAT4-deficient Th17 cultured cells from mice with experimental autoimmune encephalomyelitis (EAE) using RNA sequencing. WT and STAT4 deficient splenocytes from EAE immunized mice were cultured with MOG peptide under Th17 conditions for three days, and then total RNA was extracted from CD4 T cells for sequencing. Differential gene expression was determined using the DESeq2 algorithm. These data reveal a previously unrecognized role for STAT4 in Th17 gene expression and function.
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: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. Affymetrix Mouse Genome 430 2.0 Arrays were used to evaluate global gene expression.
Project description:RNA sequencing demonstrated that liver Ly49E+ and Ly49E- ILC1s exhibited unique transcriptional profiles and phenotypic features. scRNA-seq analysis revealed heterogeneity within both cNK and ILC1 subsets in liver. cNK cells could be further divided into three clusters, which corresponded to different developmental stages. Ly49E expression could dissect ILC1s into two subsets: Ly49E+ ILC1s and Ly49E- ILC1s, which exhibited different functional characteristics.
Project description:Type 1 IFNs can conditionally activate all of the signal transducers and activators of transcription molecules (STATs), including STAT4. The best-characterized signaling pathways use STAT1, however, and type 1 IFN inhibition of cell proliferation is STAT1 dependent. We report that type 1 IFNs can basally stimulate STAT1- and STAT4- dependent effects in CD8 T cells, but that CD8 T cells responding to infections of mice with lymphocytic choriomenigitis virus have elevated STAT4 and lower STAT1 expression with significant consequences for modifying the effects of type 1 IFN exposure. The phenotype was associated with preferential type 1 IFN activation of STAT4 as compared to STAT1. Stimulation through the TCR induced elevated STAT4 expression, and STAT4 was required for peak expansion of antigen-specific CD8 T cells, low STAT1 levels, and resistance to type 1 IFN-mediated inhibition of proliferation. Thus, a mechanism is discovered for regulating the consequences of type 1 IFN exposure in CD8 T cells, with STAT4 acting as a key molecule in driving optimal antigen-specific responses and overcoming STAT1-dependent inhibition of proliferation. CD8 T cells were purified from uninfected WT, STAT1-deficient and STAT4-deficient mice or from D8 LCMV-infected WT mice and either control treated or treated with 1x104 U mouse IFNalpha for 90 minutes.
Project description:We futher characterized genome-wide chromatin accessibility of WT and SRC-2-/- mouse liver at CT10 through DNase-Seq. In addition,chromatin accessibility was significantly reduced in SRC-2-/- mouse liver compared to WT mice at CT10. DNase-Seq was carried out in WT and SRC-2-/- mice in liver at CT10 using two doses of DNaseI.
Project description:Group 1 innate lymphoid cells (ILCs) comprising circulating natural killer (cNK) cells and tissue-resident ILC1s are critical for host defense against pathogens and tumors. Despite a growing understanding of their role in homeostasis and disease, the ontogeny of group 1 ILCs remains largely unknown. Here, we used fate mapping and single-cell transcriptomics to comprehensively investigate the origin and turnover of group 1 ILCs. While cNK cells are continuously replaced throughout life, we uncovered tissue-dependent development and turnover of ILC1s. A first wave of ILC1s emerges during embryogenesis in the liver and transiently colonizes fetal tissues. After birth, a second wave quickly replaces ILC1s in most tissues apart from the liver, where they layer with embryonic ILC1s and persist until adulthood undergoing a unique developmental program. While embryonically-derived ILC1s give rise to a cytotoxic subset, the neonatal wave establishes a helper-like subset. Our findings uncover key ontogenic features of group 1 ILCs and their association with unique cellular identities and functions.
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.