Interaction of the pioneer transcription factor GATA3 with nucleosomes
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE137794 | GEO | 2020/04/17
REPOSITORIES: GEO
Similar Datasets
Project description: Not available
| S-EPMC7434886 | biostudies-literature
Project description:Interaction of the pioneer transcription factor GATA3 with nucleosomes
| PRJNA573080 | ENA
Project description:Pioneer transcription factors bind to silent chromatin, and initiate cell fate conversion. One potential pioneer factor, GATA3, is a critical component for multiple cellular programs. GATA3 is of particular interest as it regulates gene expression in breast cancers, and low expression correlates with poor prognosis. Here we demonstrate the pioneering activity of GATA3 utilizing a cellular reprogramming system (the mesenchymal-epithelial transition) in breast cancer cells. During the epithelial transition, GATA3 catalyzes chromatin reprogramming by inducing chromatin opening, active enhancer modifications, and nucleosome remodelling. We determined that the transactivation domain is required for this chromatin reprogramming. Importantly, a mutant lacking the transactivation domain possessed the chromatin binding ability but failed to create open chromatin, suggesting binding alone is not sufficient to induce open chromatin. These data illustrate a fundamental mechanism of GATA3-mediated gene regulation, and provide evidence for a pre-engagement state of closed chromatin bound by a pioneer factor.
2016-01-27 | GSE72141 | GEO
Project description:The mechanistics by which ATP-dependent chromatin remodelers process (epi)genetic information to generate hallmark features of chromatin are fundamental for genome regulation. Here, we advance whole-genome reconstitutions into a fully definable, recombinant approach for probing how remodelers determine nucleosome positioning. Using wild type and structure-guided mutant versions of the Saccharomyces cerevisiae 15-subunit INO80 remodeler, we show that INO80-intrinsic nucleosome positioning relies on direct DNA shape read-out. This requires especially the interplay between the INO80 nuclear actin and core modules, to a lesser extent the HMG-box Nhp10 module and not histone modifications/variants or the Rvb1/2 AAA+-ATPase activity. Extrinsically, nucleosome positioning is guided by the barrier Reb1 via Ino80 ATPase activity modulation or by mere DNA double strand breaks. Taken together, we present a defined and unbiased approach to understand remodeler-mediated nucleosome positioning and delineate how INO80 processes genomic information into nucleosome positioning.
2020-04-30 | GSE145093 | GEO
Project description:We develop a chemical cleavage method that releases single nucleosome dyad-containing fragments, allowing us to precisely map both single nucleosomes and linkers with high accuracy genome-wide in budding yeast. By comparing nucleosome dyad positioning maps to existing genomic and transcriptomic data, we evaluated the contributions of sequence, transcription, histone H1 and H2A.Z in defining the chromatin landscape. A biophysical model that neglects DNA sequence is presented and shows that steric occlusion suffices to explain the salient features of nucleosome positioning. Our study indicates that steric occlusion, and not DNA sequence, is the most important determinant of genome-wide nucleosome positioning.
2018-01-12 | GSE97290 | GEO
Project description:Background: The androgen receptor (AR) is a tumor suppressor in estrogen receptor (ER) positive breast cancer, a role sustained in some ER negative breast cancers. Key factors dictating AR genomic activity in a breast context are largely unknown. Herein, we employed an unbiased chromatin immunoprecipitation-based proteomic technique to identify endogenous AR interacting co-regulatory proteins in ER positive and negative models of breast cancer to gain new insight into mechanisms of AR signaling in this disease. Results: The DNA-binding factor GATA3 is identified and validated as a novel AR interacting protein in breast cancer cells irrespective of ER status. AR activation by the natural ligand 5α-dihydrotestosterone (DHT) increases nuclear AR-GATA3 interactions, resulting in AR-dependent enrichment of GATA3 chromatin binding at a sub-set of genomic loci. Silencing GATA3 reduces but does not prevent AR DNA binding and transactivation of genes associated with AR/GATA3 co-occupied loci, indicating a co-regulatory role for GATA3 in AR signaling. DHT-induced AR/GATA3 binding coincides with upregulation of luminal differentiation genes, including EHF and KDM4B, established master regulators of a breast epithelial cell lineage. These findings are validated in a patient-derived xenograft model of breast cancer. Interaction between AR and GATA3 is also associated with AR-mediated growth inhibition in ER positive and ER negative breast cancer.
2024-01-30 | PXD047997 | Pride
Project description:The budding yeast genome is marked by 250-350 origins of DNA replication. These origins are bound by the origin recognition complex (ORC) throughout the cell cycle. ORC has known DNA binding sequence preferences which, though necessary for binding, are not sufficient to fully specify a genomic locus as being bound by ORC, indicating that the cell must use additional chromosomal cues to specify ORC binding sites and origins of replication. Using high-throughput sequencing to precisely locate both ORC binding sites and nucleosome locations genome-wide, we find that a nucleosome depleted region (NDR) and precisely positioned nucleosomes are a ubiquitous feature of yeast replication origins. The ARS consensus sequence (ACS) and adjacent sequences are sufficient to maintain the nucleosome-free properties of the NDR. We use a temperature sensitive ORC1 mutant to demonstrate that ORC is required to maintain precisely positioned nucleosomes at origins of replication. These findings demonstrate the importance of local nucleosome positioning at replication origins, and that chromatin organization is an important determinant of origin selection. Examination of nucleosome positioning in wild-type and orc1-161ts mutant S. cerevisiae at room temperature and heatshock temperatures. Examination of ORC binding locations by ChIP-seq. All reported coordinates are based on the SGD genome build released 12/16/2005.
2010-03-19 | E-GEOD-16926 | biostudies-arrayexpress
Project description:Positioning of nucleosomes along DNA is an integral regulator of chromatin accessibility and gene expression in diverse cell types. However, the precise nature of how post-translational modification of histones such as activating trimethylated histone 3 lysine 4 (H3K4me3), or histone demethylases including the H3K4 demethylase, KDM5B, impacts nucleosome positioning around transcriptional start sites (TSS) of active genes is poorly understood. Here, we report that KDM5B is a critical regulator of nucleosome positioning in embryonic stem (ES) cells. Micrococcal nuclease sequencing (MNase-Seq) revealed increased enrichment of nucleosomes around TSS regions and DNase I hypersensitive sites in KDM5B-depleted ES cells. Moreover, depletion of KDM5B resulted in a widespread redistribution and disorganization of nucleosomes in a sequence-dependent manner. Dysregulated nucleosome phasing was also evident in KDM5B-depleted ES cells, including asynchronous nucleosome spacing surrounding TSS regions, where nucleosome variance was positively correlated with the degree of asynchronous phasing. The redistribution of nucleosomes around TSS regions in KDM5B-depleted ES cells is correlated with dysregulated gene expression, and altered H3K4me3 and RNA polymerase II occupancy. In addition, we found that DNA shape features varied significantly at regions with shifted nucleosomes. Altogether, our data support a role for KDM5B in regulating nucleosome positioning in ES cells.
2019-04-23 | GSE123249 | GEO
Project description:Estrogen Receptor (ER) is a steroid hormone receptor that regulates epithelial genes in breast cancer. ER forms a regulatory network with the other transcription factors, FOXA1 and GATA3. GATA3 is known to be capable of specifying chromatin localization of FOXA1 and ER. GATA3 has been identified as one of the most frequently mutated genes in breast cancer. However, how GATA3 mutations impact this transcriptional network is unknown. Here we investigate the function of one of the recurrent patient-derived GATA3 mutations (R330fs) for this regulatory network. Genomic analysis indicates that the R330fs mutant can disrupt the cooperative action of ER, FOXA1, and GATA3, and induce chromatin relocalization of these factors. Relocalizations of ER and FOXA1 are associated with altered chromatin architectures leading to differential gene expression in the GATA3 mutant cells. These results suggest the active role of GATA3 mutants in ER positive breast tumors.
2020-02-27 | GSE130703 | GEO
Project description:Nucleosome positioning governs access to eukaryotic genomes. Many genes show a stereotypic organisation at their 5’ end: a nucleosome free region just upstream of the transcription start site (TSS) followed by a regular nucleosomal array over the coding region. The determinants for this pervasive pattern are unclear, but nucleosome remodeling ATPases likely are critical. Now we employ deletion mutants to study the role of nucleosome remodeling ATPases in global nucleosome positioning in S. pombe and the corresponding changes in expression patterns. We find a striking evolutionary shift in remodeling enzyme usage between budding and fission yeast. The S. pombe RSC remodeling complex seems not involved in nucleosome positioning, despite its prominent role in S. cerevisiae. While lacking ISWI-type remodelers, S. pombe has two CHD1-type ATPases, Hrp1 and Hrp3. We demonstrate nucleosome spacing activity for both in vitro, and together they are essential for linking regular genic arrays to most TSSs in vivo. Impaired chromatin may but need not lead to changes in transcription. The absence of both causes changed expression for about 20% and increased antisense transcription for 15% of all annotated elements.
2012-10-11 | GSE41024 | GEO