Mammalian SWI/SNF collaborates with a polycomb-associated protein to regulate germ line transcription in the mouse [CUT&RUN]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE128988 | GEO | 2019/05/09
REPOSITORIES: GEO
Similar Datasets
Project description:ChIP-seq of BRG1 and histone modifications from spermatogenic cells
2019-05-09 | GSE119177 | GEO
Project description:RNA-seq on spermatogenic cells from P12 testes
2019-05-09 | GSE119178 | GEO
Project description:ATAC-seq on spermatogenic cells from P12 and P18 testes
2019-05-09 | GSE119176 | GEO
Project description:A deficiency in BRG1, the catalytic subunit of the SWI/SNF chromatin remodeling complex, results in a meiotic arrest during spermatogenesis. Here, we explore the causative mechanisms. BRG1 is preferentially enriched at active promoters of genes essential for spermatogonial pluripotency and meiosis. In contrast, BRG1 is also associated with the repression of somatic genes. Chromatin accessibility at these target promoters is dependent upon BRG1. These results favor a model in which BRG1 coordinates spermatogenic transcription to ensure meiotic progression. In spermatocytes, BRG1 interacts with SCML2, a testis-specific PRC1 factor that is associated with the repression of somatic genes. We present evidence to suggest that BRG1 and SCML2 concordantly regulate genes during meiosis. Furthermore, BRG1 is required for the proper localization of SCML2 and its associated deubiquitylase, USP7, to the sex chromosomes during pachynema. SCML2-associated mono-ubiquitylation of histone H2A lysine 119 (H2AK119ub1) and acetylation of histone lysine 27 (H3K27ac) are elevated in Brg1cKO testes. Coincidentally, the PRC1 ubiquitin ligase RNF2 is activated while a histone H2A/H2B deubiquitylase USP3 is repressed. Thus, BRG1 impacts the male epigenome by influencing the localization and expression of epigenetic modifiers. This mechanism highlights a novel paradigm of cooperativity between SWI/SNF and PRC1.
| S-EPMC6803380 | biostudies-literature
Project description:Epigenetic alterations have been increasingly implicated in oncogenesis. Analysis of Drosophila mutants suggests that Polycomb and SWI/SNF complexes can serve antagonistic developmental roles. However, the relevance of this relationship to human disease is unclear. Here, we have investigated functional relationships between these epigenetic regulators in oncogenic transformation. Mechanistically, we show that loss of the SNF5 tumor suppressor leads to elevated expression of the Polycomb gene EZH2 and that Polycomb targets are broadly H3K27-trimethylated and repressed in SNF5-deficient fibroblasts and cancers. Further, we show antagonism between SNF5 and EZH2 in the regulation of stem cell-associated programs and that Snf5 loss activates those programs. Finally, using conditional mouse models, we show that inactivation of Ezh2 blocks tumor formation driven by Snf5 loss.
| S-EPMC2957473 | biostudies-literature
Project description:The molecular mechanisms of neurogenic fate determination are of particular importance in light of the need to regenerate neurons. However the molecular logic of neurogenic fate determination is still ill understood, even though some key transcription factors have been implicated. Here we describe how one of these, the transcription factor Pax6, regulates adult neurogenesis by initiating a cross-regulatory network of 3 transcription factors executing neuronal fate and regulating genes required for neuronal differentiation. This network is initiated and driven to sufficiently high expression levels by the transcription factor Pax6 in close interaction with Brg1-containing SWI/SNF chromatin remodeling factors. Genetic deletion of either Pax6 or Brg1, the ATPase unit of the SWI/SNF complex, in neural stem cells of the adult mouse subependymal zone results in a fate conversion to distinct glial subtypes most pronounced when neuroblasts leave the neurogenic niche. Consistent with the phenocopy in vivo virtually all genes down-regulated by Brg1 deletion have Pax6-binding motifs. Amongst the few down-stream transcription factors are Sox11, Nfib and Brn4 that crossregulate each other and rescue neurogenesis also in direct reprogramming in the absence of Brg1 (or Pax6). Thus the function of Pax6-SWI/SNF is necessary and sufficient for neuronal fate maintenance and initiates a cross-regulatory effector network required for neuronal fate execution and maintenance to counteract glial differentiation in the adult brain. This identifies a novel role highly specific role of a chromatin-remodelling complex in stabilizing fate decisions in normal and forced neurogenesis. We performed gene expression microarray analysis on tissue derived from the SEZ or from the core region of the olfactory bulb from Brg1 cKO and control mice
2013-08-01 | E-GEOD-39362 | biostudies-arrayexpress
Project description:Ferroptosis is an iron-dependent cell death mechanism characterized by an accumulation of toxic lipid peroxides and membrane rupture. The glutathione dependent enzyme, GPX4 (glutathione peroxidase 4), prevents ferroptosis by reducing these lipid peroxides into non-toxic lipid alcohols. Ferroptosis induction by GPX4 inhibition has emerged as a vulnerability of cancer cells, thus highlighting the need to identify ferroptosis regulators that may be exploited therapeutically. Through genome-wide screens and a series of genetic, genomic, and quantitative imaging approaches, we identify the SWI-SNF ATPases BRM and BRG1 as ferroptosis suppressors. Mechanistically, they directly bind to and catalytically increase chromatin accessibility at NRF2 target loci, thus boosting NRF2 transcriptional output. This primes cells to counter lipid peroxidation and confers resistance to GPX4 inhibition and ferroptosis. Importantly, we demonstrate that the BRM/BRG1-ferroptosis connection can be leveraged to enhance the paralog dependency of BRG1-mutant lung cancer cells on BRM, especially in lines that are less sensitive to BRM inhibition or degradation. Our data reveal ferroptosis induction as a potential avenue for broadening the efficacy of BRM degraders/inhibitors and define a specific genetic context for exploiting GPX4 dependency.
2024-09-22 | GSE245237 | GEO
Project description:Cancer cells frequently depend on chromatin regulatory activities to maintain a malignant phenotype. Here, we show that leukemia cells require the mammalian SWI/SNF chromatin remodeling complex for their survival and aberrant self-renewal potential. While Brg1, an ATPase subunit of SWI/SNF, is known to suppress tumor formation in several cancer types, we found that leukemia cells instead rely on Brg1 to support their oncogenic transcriptional program, which includes Myc as one of its key targets. To account for this context-specific function, we identify a cluster of lineage-specific enhancers located 1.7 megabases downstream of Myc that are occupied by SWI/SNF, as well as the BET protein Brd4. Brg1 is required at these distal elements to maintain transcription factor occupancy and for long-range chromatin looping interactions with the Myc promoter. Notably, these distal Myc enhancers coincide with a region that is focally amplified in 3% of acute myeloid leukemia. Together, these findings define a leukemia maintenance function for SWI/SNF that is linked to enhancer-mediated gene regulation, providing general insights into how cancer cells exploit transcriptional coactivators to maintain oncogenic gene expression programs In order to understanding the transcription regulation network downstream of Brg1 in murine AML, we performed microarray in murine MLL-AF9/NrasG12D cell line under the condition that Brg1 was suppressed by three independent shRNAs for 96h.
2013-12-02 | E-GEOD-52231 | biostudies-arrayexpress
Project description:Cancer cells frequently depend on chromatin regulatory activities to maintain a malignant phenotype. Here, we show that leukemia cells require the mammalian SWI/SNF chromatin remodeling complex for their survival and aberrant self-renewal potential. While Brg1, an ATPase subunit of SWI/SNF, is known to suppress tumor formation in several cancer types, we found that leukemia cells instead rely on Brg1 to support their oncogenic transcriptional program, which includes Myc as one of its key targets. To account for this context-specific function, we identify a cluster of lineage-specific enhancers located 1.7 megabases downstream of Myc that are occupied by SWI/SNF, as well as the BET protein Brd4. Brg1 is required at these distal elements to maintain transcription factor occupancy and for long-range chromatin looping interactions with the Myc promoter. Notably, these distal Myc enhancers coincide with a region that is focally amplified in 3% of acute myeloid leukemia. Together, these findings define a leukemia maintenance function for SWI/SNF that is linked to enhancer-mediated gene regulation, providing general insights into how cancer cells exploit transcriptional coactivators to maintain oncogenic gene expression programs In order to understanding the lineage specific requirement of coactivaor, such as Brg1 and Brd4, in AML, we performed ChIP-seq with Brg1, Brd4 together with histone modification marks in murine MLL-AF9/NrasG12D AML cell line to search tissue specific cis regulation element that can be accounted for the leukemia specific dependence.
2013-12-02 | E-GEOD-52277 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2019-05-09 | GSE119179 | GEO