Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression Analysis of PU.1 binding sites in mo-DC
Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression
Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression
Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression
Project description:<p>Small cell carcinoma of the ovary-hypercalcemic type (SCCOHT) is a rare and aggressive form of ovarian cancer afflicting young women at a median age of 24 years. SCCOHTs are characterized by loss of protein expression of SWI/SNF chromatin remodeling ATPases SMARCA4 and SMARCA2 through mutation and epigenetic silencing, respectively. This study aims to establish gene expression profiles of this cancer through RNA-Seq of four pathologically confirmed cases of SCCOHT tumors.</p>
Project description:Mitochondrial trifunctional protein deficiency, due to mutations in hydratase subunit A (HADHA), results in sudden infant death syndrome (SIDS) with no cure. To reveal the disease etiology, we generated stem cell-derived cardiomyocytes from HADHA-deficient hiPSCs and accelerated their maturation via a novel, engineered MicroRNA Maturation Cocktail (MiMaC) that upregulated the epigenetic regulator, HOPX. Fatty acid challenged MiMaC treated HADHA mutant cardiomyocytes manifested the disease phenotype: defective calcium dynamics and repolarization kinetics which resulted in a pro-arrhythmic state. Single cell RNA-seq revealed a novel cardiomyocyte developmental intermediate, based on metabolic gene expression. This intermediate gave rise to mature-like cardiomyocytes in control cells but, mutant cells transitioned to a pathological state with reduced fatty acid beta-oxidation (FAO), reduced mitochondrial proton gradient, disrupted cristae structure and defective cardiolipin remodeling. This study reveals that TFPa/HADHA, a MLCL-AT-like enzyme, is required for FAO and cardiolipin remodeling, essential for functional mitochondria in human cardiomyocytes.
Project description:KSRP knock-down and BMP2 treatment produce a largely overlapping reshape of the transcriptome in C2C12 cells. microRNAs (miRNAs) are essential regulators of development, physiology, and evolution with miRNA biogenesis being strictly controlled at multiple levels. Regulatory proteins, such as KH-type splicing regulatory protein (KSRP), modulate rates and timing of the enzymatic reactions responsible for maturation of select miRNAs from their primary transcripts in response to specific stimuli. Induction of myogenic miRNAs (myomiRs) is essential for muscle differentiation with KSRP phosphorylation being required to convey myogenic signals to enhanced myomiR maturation. Here we show that either KSRP silencing or Bone Morphogenetic Protein (BMP)2-signaling activation in mesenchimal C2C12 cells prevented myogenic differentiation while induced osteoblastic differentiation as revealed by the reshaping of the whole transcriptome analyzed by RNA deep-sequencing. The most striking feature common to both BMP2 signaling activation and KSRP silencing was a blockade of myomiR maturation. Our results demonstrate that phosphorylated SMAD proteins, the transducers of BMP signaling, associate with KSRP and block its interaction with primary-myomiRs. This, in turn, abrogates KSRP-dependent myomiR maturation with the knock-down of SMAD4, 5, and 9 being able to rescue KSRP function. SMAD-induced blockade of KSRP-dependent myomiR maturation, in parallel to the well known SMAD function on gene transcription, inhibits C2C12 cell differentiation into myofibers and contributes to orient cells towards osteoblast lineage. We propose that remodeling of co-regulatory complexes affecting primary-miRNA processing is a mechanism well suited to guide cell fate determination in eukaryotes. Total RNA was prepared from 1. untreated mock-transfected C2C12 cells; 2. BMP2-treated mock-transfected C2C12 cells; 3. untreated shKSRP-transfected C2C12 cells and analyzed by RNA-seq