The Drosophila histone variant H2Av facilitates Notch signaling activity in a two-tier regulatory fashion
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1213076 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Background H2Av is evolutionarily conserved H2A variant protein involved in the regulation of transcription. The Tip60 complex is recruited by different transcription factors to facilitate the incorporation and acetylation of H2Av, thereby influencing target gene expression by modifying the stability of the nucleosome that occludes the transcription start site. The Tip60-H2Av module is involved in various developmental processes, though its precise roles are not yet fully understood. Methods RNA interference and gene knock-out technology were used screen essential genes in regulating Notch signaling pathway. We use immunostaining method to detect the protein level of H2Av, Tip60 complex as well as Notch signaling pathway components. Chromatin immunoprecipitation assay was performed to detect the specific bind of H2Av in E(spl)-Complex and Su(H) genes. Result Here we report that H2Av is required for Notch signaling activation during Drosophila wing development. H2Av depletion disrupts the expression of Notch target genes, resulting in wing marginal defects. Unexpectedly, we find that H2Av regulates the expression of Su(H) gene which encodes the transcription factor of the Notch signaling cascade. We further demonstrate that the Tip60 complex modulates the transcription of both Notch targets and Su(H) likely through H2Av. Based on these observations, we propose a model that the Tip60-H2Av module facilitates Notch pathway activation by simultaneously promoting the expression of both the target genes and the transcription factor. Conclusion This study offers insights into the diverse roles of the Tip60-H2Av module in Notch pathway activation by identifying a novel two-tier regulatory mechanism which may also be utilized by other chromatin remodeling factors. Key words H2Av, Notch, Su(H), Drosophila, Tip60
2025-01-24 | GSE287479 | GEO
Project description:Dysregulation of the Notch-RBPJ signaling pathway has been found associated with various human diseases including cancers; however, precisely how this key signaling pathway is fine-tuned via its interactors and modifications is still largely unknown. In this study, using a proteomic approach, we identified FBXO42 as a novel RBPJ interactor. FBXO42 promotes RBPJ polyubiquitination on lysine (K) 175 via K63 linkage, which enhances the association of RBPJ with chromatin remodeling complexes and induces a global chromatin relaxation. Genetically depleting FBXO42 or pharmacologically targeting its E3 ligase activity attenuates the Notch signaling-related leukemia development in vivo. Taken together, our findings not only revealed FBXO42 as a critical regulator of the Notch pathway by modulating RBPJ-dependent global chromatin landscape changes, but also provide insights into the therapeutic intervention of the Notch pathway for leukemia treatment.
2022-10-13 | PXD034938 | Pride
Project description:This randomized phase I/II clinical trial is studying the side effects and best dose of gamma-secretase/notch signalling pathway inhibitor RO4929097 when given together with vismodegib and to see how well they work in treating patients with advanced or metastatic sarcoma. Vismodegib may slow the growth of tumor cells. Gamma-secretase/notch signalling pathway inhibitor RO4929097 may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving vismodegib together with gamma-secretase/notch signalling pathway inhibitor RO4929097 may be an effective treatment for sarcoma.
| 2091475 | ecrin-mdr-crc
Project description:The study deals with the elucidation of potential interaction partners of the intracellular domain of the transmembrane receptor Notch1, termed NICD. The NICD is released from the cytoplasmic tail of the Notch receptor by gamma-secretase treatment and translocated as a transcription factor to the nucleus. Here, virally transduced recombinant NICD constructs (wild-type and deltaEP hyperactive mutant) were employed for AP-MS with the aim of identifying novel NICD interactors in a murine T cell leukemia cell line.
2018-06-25 | PXD008747 | Pride
Project description:Notch is needed for T cell development and is a common oncogenic driver in T cell acute lymphoblastic leukemia. Myc is a critical target of Notch in normal and malignant pre-T cells, but how Notch regulates Myc is unknown. Here, we identify a distal enhancer located >1 Mb 3' of human and murine Myc that binds Notch transcription complexes and physically interacts with the Myc proximal promoter. The Notch1 binding element in this region activates reporter genes in a Notch-dependent, cell context-specific fashion that requires a conserved Notch complex binding site. Acute changes in Notch activation produce rapid changes in H3K27 acetylation across the entire enhancer (a region spanning >600 kb) that correlate with Myc expression. This broad Notch-influenced region is comprised of an enhancer region containing multiple domains, recognizable as discrete H3K27 acetylation peaks. Leukemia cells selected for resistance to Notch inhibitors express Myc despite epigenetic silencing of enhancer domains near the Notch transcription complex binding sites. Notch-independent expression of Myc in resistant cells is highly sensitive to inhibitors of Brd4, a change in drug sensitivity that is accompanied by preferential association of the Myc promoter with more 3’ enhancer domains that are strongly dependent on Brd4 for function. These findings indicate that altered long-range enhancer activity can mediate resistance to targeted therapies and provide a mechanistic rationale for combined targeting of Notch and Brd4 in leukemia.
2014-11-11 | GSE61504 | GEO
Project description:Loss or damage to the mandible due to trauma, treatment of oral malignancies, and other diseases is currently treated using bone grafting techniques that suffer from numerous shortcomings and contraindications. Zebrafish naturally heal large injuries to their mandibular bone, and thus offer an opportunity to understand how to boost intrinsic healing ability. Using a novel her6:mCherry Notch reporter, we show that canonical Notch signaling is induced during the initial stages of cartilage callus formation in both mesenchymal cells and chondrocytes. We also show that modulation of Notch signaling during the initial postoperative period results in lasting changes to regenerate bone quantity one month later. Notch signaling is required for mandibular bone healing, as pharmacological inhibition of Notch signaling blocks cartilage callus formation and results in non-union. Conversely, conditional transgenic activation of Notch signaling accelerates regenerative ossification. Mechanistically, we report that postoperative Notch signaling regulates multiple phases of chondroid regeneration and patterns callus metabolic landscape. Given conserved functions of Notch signaling in bone repair across vertebrates, we propose that targeted activation of Notch signaling during the early phases of bone healing may have therapeutic value.
2022-03-07 | PXD027280 | Pride
Project description:A bacterial histone binds DNA in an unorthodox fashion
| PRJNA910144 | ENA
Project description:NOTCH1 is a transmembrane receptor that initiates the Notch signaling pathway involved in embryonic development and maintenance of adult tissue homeostasis. The extracellular part of NOTCH1 is composed largely of EGF-like domains (EGFs) many of which can be O-fucosylated by protein O-fucosyltransferase 1 (POFUT1). O-fucosylation of NOTCH1 is necessary for its function. The Notch pathway is deregulated in many cancers, and alteration of POFUT1 has been reported in some cancers. Using the Biomuta and COSMIC databases, we selected 9 NOTCH1 variants that could cause a change in O-fucosylation of key EGFs. Cell-based N1 signaling assays, Notch ligand-binding assays and cell surface N1 analysis were used to determine the effect of each mutation on Notch activation. Then mass spectral glycoproteomic site mapping was used to identify alterations in the O-fucosylation of EGFs containing the selected mutation. One of the variants had few effects, two lead to a gain of function (GOF) and six to a loss of function (LOF). Most GOF and LOF could be associated with a change in O-fucosylation. Finally, by comparing our results with known NOTCH1 alterations in cancers from which our mutations originated, we were able to establish a correlation between our results and the known GOF or LOF of NOTCH1 in these cancers. This study shows that point mutations in NOTCH1 can lead to alterations in O-fucosylation that deregulate the Notch pathway and be associated with cancer processes.
2022-10-21 | PXD036345 | Pride
Project description:Dysregulation of the Notch-RBPJ signaling pathway has been found associated with various human diseases including cancers; however, precisely how this key signaling pathway is fine-tuned via its interactors and modifications is still largely unknown. In this study, using a proteomic approach, we identified FBXO42 as a novel RBPJ interactor. FBXO42 promotes RBPJ polyubiquitination on lysine (K) 175 via K63 linkage, which enhances the association of RBPJ with chromatin remodeling complexes and induces a global chromatin relaxation. Genetically depleting FBXO42 or pharmacologically targeting its E3 ligase activity attenuates the Notch signaling-related leukemia development in vivo. Taken together, our findings not only revealed FBXO42 as a critical regulator of the Notch pathway by modulating RBPJ-dependent global chromatin landscape changes, but also provide insights into the therapeutic intervention of the Notch pathway for leukemia treatment.
2022-07-31 | GSE206985 | GEO