Project description:We used microarrays to asses gene expression in 3T3 fibroblasts, after knock-down of Brg1 and Brm using stable shRNA interference. Cells were treated with 5ng/ml mouse TNF-alpha to stimulate inducible gene activation.
Project description:Brg1 and Brm function as alternative core enzymatic ATPases of SWI/SNF complex in vertebrates, with clear homologs in zebrafish. Brg1 (but not Brm) is required for early cleavage-stage transcription in mice, but where and how Brg1 or Brm impact chromatin in early embryos remains unexplored. Here, we utilize zebrafish embryos to provide the first simultaneous genome-wide profiling of Brg1 and Brm occupancy in any organism/cell type, alongside our profiling of open chromatin and RNA polymerase II. We reveal shared and unique loci for Brg1 and Brm, their shared occupancy of open chromatin and particular developmental promoters, and higher transcription at co-occupied genes. Interestingly, only Brg1 is strongly associated with active histone modifications. Strikingly, only Brm commonly occupies gene bodies, overlapping precisely with Pol II. Functional experiments involving Pol II elongation inhibition alongside bioinformatic analyses suggest that Brm travels with Pol II into gene bodies, primarily at short, very highly-transcribed genes with few introns. Taken together, our results support roles for Brg1 primarily at promoters and enhancers, and for Brm in association with Pol II in elongation through chromatin within gene bodies during genome-wide transcriptional activation
Project description:Brg1 and Brm function as alternative core enzymatic ATPases of SWI/SNF complex in vertebrates, with clear homologs in zebrafish. Brg1 (but not Brm) is required for early cleavage-stage transcription in mice, but where and how Brg1 or Brm impact chromatin in early embryos remains unexplored. Here, we utilize zebrafish embryos to provide the first simultaneous genome-wide profiling of Brg1 and Brm occupancy in any organism/cell type, alongside our profiling of open chromatin and RNA polymerase II. We reveal shared and unique loci for Brg1 and Brm, their shared occupancy of open chromatin and particular developmental promoters, and higher transcription at co-occupied genes. Interestingly, only Brg1 is strongly associated with active histone modifications. Strikingly, only Brm commonly occupies gene bodies, overlapping precisely with Pol II. Functional experiments involving Pol II elongation inhibition alongside bioinformatic analyses suggest that Brm travels with Pol II into gene bodies, primarily at short, very highly-transcribed genes with few introns. Taken together, our results support roles for Brg1 primarily at promoters and enhancers, and for Brm in association with Pol II in elongation through chromatin within gene bodies during genome-wide transcriptional activation
Project description:We performed Brg1 (Smarac4) knock-down by siRNA in murine primary bone marrow-derived macrophages and profiled the effect on gene expression by RNAseq after lipopolysaccharide (LPS) or LPS plus dexamethasone (Dex) treatment. Brg1 knock-down cells are compared to cells treated with a control siRNA. We analysed the requirement of Brg1/Smarca4 for the expression of inflammatory and glucocorticoid receptor target genes.
Project description:We exogenously expressed the SWI/SNF ATPase catalytic subunits BRG1 and BRM in the lacking cell line C33A, and compared the differences with mock transfected cell at gene expression and alternative splicing level.
Project description:Identification of gene expression changes in wild type versus mutant mouse hearts where Brg1 and Brm were knocked out in adult cardiomyocytes.
Project description:The SWI/SNF complex remodels chromatin in an ATP-dependent manner through the ATPase subunits BRG1 and BRM. Chromatin remodeling alters nucleosome structure to change gene expression, however aberrant remodeling and gene expression can result in cancer. The function and localization on chromatin of the SWI/SNF complex depends on the protein makeup of the complex. Here we report the protein-protein interactions of wild-type BRG1 or mutant BRG1 in which the HSA domain has been deleted (BRG1-HSA). We demonstrate the interaction of BRG1 with most SWI/SNF complex members and a failure of a number of these members to interact with BRG1-HSA. These results demonstrate that the HSA domain of BRG1 is a critical interaction platform for the correct formation of SWI/SNF remodeling complexes.
Project description:RNA-seq analysis for C2C12 myoblasts knocked down for either only-BRG1 or only-BRM or both BRG1 and BRM. Cells were treated with an siRNA SMARTpools of four oligos each targeting either BRG1 (siGENOME mouse Smarca4 pool #M-041135-01-0020) or BRM (siGENOME mouse Smarca2 pool #M-056591-00-0020) or both. Control samples were treated with non-targeting scrambled oligos (siRNA SMARTpool ON-TARGETplus scrambled non-targeting pool # D-001810-10-20). siRNA pools were purchased from Dharmacon, Horizon Discovery Ltd., USA.