Project description:The chromatin remodeler Chd4, a member of the nucleosome remodeling and deacetylase (NuRD) repressive complex, is essential for the expansion and regenerative functions of satellite cells.
Project description:We performed a label-free LC-MS/MS study to analyse the role of Chd4 regulation in MuSC in suppressing genes enabling programmed cell death as part of the muscle regeneration program. Lox-cre recombination was used to create a deletion mutant of the CHD4 chromatin modifier (exons 12-21). A pseudo "infection" with GFP was used as control. Proteomics analysis here serves as a method to compare the differentially deregulated proteins upon knockdown of Chd4 in MuSCs using Adenoviral CRE recombination.
Project description:Glioblastomas (GBM) harbor subpopulations of therapy-resistant tumor initiating cells (TICs) that are self-renewing and multipotent. To understand the regulation of the TIC state, we performed an image-based screen for genes regulating GBM TIC maintenance and identified ZFHX4, a 397-kDa transcription factor. ZFHX4 is required to maintain TIC-associated phenotypes in vitro, suggesting that ZFHX4 regulates TIC differentiation, and its suppression increases glioma-free survival in intracranial xenografts. ZFHX4 interacts with CHD4, a core member of the NuRD (nucleosome remodeling and deacetylase) complex. ZFHX4 and CHD4 bind to overlapping sets of genomic loci and control similar gene expression programs. Using expression data derived from GBM patients, we demonstrate ZFHX4 is a master regulator of CHD4-mediated gene expression. These observations define ZFHX4 as a regulatory factor that links the chromatin remodeling NuRD complex and the GBM TIC state. Examination of binding of ZFHX4 and CHD4 across the human genome, using the 0308 tumor initiating cell line. Two replicates for each protein, compared to whole cell extract inputs.
Project description:Cell-lineage specification is a tightly regulated process that is dependent on appropriate expression of lineage- and developmental stage-specific transcriptional programs. Accessibility and inaccessibility of gene loci are controlled dynamically during cellular development. Here, we show that Chromodomain Helicase DNA-binding protein 4 (CHD4), a major ATPase/helicase subunit of Nucleosome Remodeling and Deacetylase Complexes (NuRD) in lymphocytes, is essential for specification of the early B cell lineage transcriptional program. In the absence of CHD4 in early B cell progenitors in vivo, B cell progenitors are arrested at an early pro-B-like stage of development, unresponsive to IL-7 receptor signaling and complete V(D)J rearrangements at Igh loci inefficiently. Importantly, CHD4-deficient B cells express a significant number of non-B cell lineage genes, including genes involved in the development of other hematopoietic lineages and neuronal cells. The absence of CHD4 increased chromatin accessibility at hundreds of these gene loci, suggesting that its ability to repress transcription by mobilizing nucleosomes and compacting chromatin is a barrier against inappropriate transcription. Together, our data demonstrate the importance of CHD4 in establishing and maintaining an appropriate transcriptome in early B lymphopoiesis via chromatin accessibility.
Project description:Cell-lineage specification is a tightly regulated process that is dependent on appropriate expression of lineage- and developmental stage-specific transcriptional programs. Accessibility and inaccessibility of gene loci are controlled dynamically during cellular development. Here, we show that Chromodomain Helicase DNA-binding protein 4 (CHD4), a major ATPase/helicase subunit of Nucleosome Remodeling and Deacetylase Complexes (NuRD) in lymphocytes, is essential for specification of the early B cell lineage transcriptional program. In the absence of CHD4 in early B cell progenitors in vivo, B cell progenitors are arrested at an early pro-B-like stage of development, unresponsive to IL-7 receptor signaling and complete V(D)J rearrangements at Igh loci inefficiently. Importantly, CHD4-deficient B cells express a significant number of non-B cell lineage genes, including genes involved in the development of other hematopoietic lineages and neuronal cells. The absence of CHD4 increased chromatin accessibility at hundreds of these gene loci, suggesting that its ability to repress transcription by mobilizing nucleosomes and compacting chromatin is a barrier against inappropriate transcription. Together, our data demonstrate the importance of CHD4 in establishing and maintaining an appropriate transcriptome in early B lymphopoiesis via chromatin accessibility.
Project description:ZFHX4 and CHD4 suppression independently shift tumor initiating cells out of a stem like state and toward a differentiated morphology. After gene suppression via transduction of a lentivirally mediated shRNA construct, RNA was extracted 3 and 5 days later and was hybridized on Affymetrix microarrays. Total RNA was extracted 3 and 5 days after shRNA transduction of 0308 TICs, for 3 (for CHD4) or 5 (ZFHX4) independent experiments. Complementary RNA synthesis and hybridization/scanning of U133 plus 2.0 microarrays using GeneChip products (Affymetrix) was done as described in the GeneChip manual.
Project description:B cell specification and identity are controlled by transcription factors and cytokine receptors that drive the expression of stage-specific transcriptomes during lineage progression. A key feature of these mechanisms is the repression of inappropriate transcription. Here, we utilized RNA-seq to demonstrate that chromodomain helicase DNA-binding protein 4 (CHD4), an ATPase/helicase subunit of Mi-2/NuRD chromatin remodeling complexes, is essential for B cell identity. In mice that lack CHD4 selectively in the B lineage, defects include developmental arrest at the early pro-B cell stage. While many pro-B-specific genes are expressed in the mutant cells, transcripts that are normally restricted to other tissues including pancreas and bone are expressed out of context. Moreover, CHD4-deficient pro-B cells do not proliferate in response to IL-7, exhibit greatly decreased utilization of distal VH segments and accumulate DNA damage. Together, our data confirm the importance of CHD4 and NuRD complexes for the generation of functional B cells.
Project description:Our study reveal that Chd4 is essential for stemness maintenance of ESCs. As Chd4 deficient ESCs show attentuated self-renewal ability and induced differentiation marker gene expression. To confirm the effect of Chd4 on the transcriptome profile of ESCs, we performed microarray analyses for Chd4 deficient ESCs.