Project description:We examined how MED23 regulates SRF-targeted genes by comparing WT and Med23 KO mouse embryonic fibroblasts (MEFs) in the presence or absence of serum-stimulation (for 30 and 90 min). To investigate whether MAL antagonizes MED23 in the adipocyte lineage program, we compared the gene expression changes resulting from Mal overexpression (oxMal) and Med23 deficiency (siMed23) in 10T1/2 cell. In MEF cells, we examined SRF-dependent gene expression in three time points (0, 30, 90min) and two conditions (WT and KO). In 10T1/2 cells, we used three treatment conditions (Mal overexpression, Med23 knockdown, and treatment of both Mal overexpression and Med23 knockdown) with control (no treatment).
Project description:We examined how MED23 regulates SRF-targeted genes by comparing WT and Med23 KO mouse embryonic fibroblasts (MEFs) in the presence or absence of serum-stimulation (for 30 and 90 min). To investigate whether MAL antagonizes MED23 in the adipocyte lineage program, we compared the gene expression changes resulting from Mal overexpression (oxMal) and Med23 deficiency (siMed23) in 10T1/2 cell.
Project description:Affymetrix MOE430A arrays. Mouse embryonic fibroblasts (MEFs) from E11 passaged through crisis. Starved in 0.5% FBS for 16 h then stimulated by 20% serum final concentration for 30 minutes. The purpose was to identify genes affected by the loss of MED23 protein (subunit of the mediator complex). Samples were assayed in duplicate (Set 1 and Set 2) for starved state and serum state cells. Cells starved in low-serum (0.5%) for 16 h then add final conc. 20% FBS for 30 minutes. Harvest total RNA from duplicate samples. One sample set is kept starved and serves as the baseline. The other set is stimulated. This is done for both wild-type cell and the Med23-/- KO cells. We looked for gene expression fold changes greater than 2 (plus or minus) to find genes affected for serum stimulation by the loss of MED23, looking in detail at immediate early genes like Egr1.
Project description:The Mediator complex orchestrates multiple transcription factors with the Pol II apparatus for precise transcriptional control. However, its interplay with the surrounding chromatin remains poorly understood. Here, we analyze differential histone modifications between WT and MED23-/- (KO) cells and identify H2B mono-ubiquitination at lysine 120 (H2Bub) as a MED23-dependent histone modification. Using tandem affinity purification and mass spectrometry, we find that MED23 associates with the RNF20/40 complex, the enzyme for H2Bub, and show that this association is critical for the recruitment of RNF20/40 to chromatin. In a cell-free system, Mediator directly and substantially increases H2Bub on recombinant chromatin through its cooperation with RNF20/40 and the PAF complex. Integrative genome-wide analyses show that MED23 depletion specifically reduces H2Bub on a subset of MED23-contolled genes. Importantly, MED23-coupled H2Bub levels are oppositely regulated during myogenesis and lung carcinogenesis. In sum, these results establish a mechanistic link between the Mediator complex and a critical chromatin modification in coordinating transcription with cell growth and differentiation. To examine the enrichment of H2B ubiquitination, Pol II, H3K4me3, H3K79me3 in WT and KO MED23 MEF cells, we performed H2Bub ChIP-seq, Pol II ChIP-seq, H3K4me3 ChIP-seq and H3K79me3 ChIP-seq assays. 10 high-throughput sequencing data were deposited and WT, KO input data were controls for peak calling.
Project description:To understand the mechanisms through which JunB regulates Tregs-mediated immune regulation, we examined the global gene expression profiles in the JunB WT and KO Tregs by performing RNA sequencing (RNA-seq) analysis.