Conditional ablation of the Notch2 receptor in the ocular lens
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE31643 | GEO | 2011/12/31
SECONDARY ACCESSION(S): PRJNA145319
REPOSITORIES: GEO
Similar Datasets
Project description:Notch signaling is essential for proper lens development, however the specific requirements of individual Notch receptors has not been previously investigated. Here we report the lens phenotypes of Notch2 conditionally mutant mice, which exhibited severe microphthalmia, reduced pupillary openings, disrupted fiber cell morphology, eventual loss of the anterior epithelium, fiber cell dysgenesis, and cataracts. Notch2 mutants also had a persistent lens stalk phenotype at E11.5, and aberrant DNA synthesis in the fiber cell compartment by E14.5. Gene expression analyses showed elevated levels of the cell cycle regulators Cdkn1a (p21Cip1), Ccnd2 (CyclinD2) and Trp63 (p63) that negatively regulates Wnt signaling. Although removal of Notch2 phenocopied the increased proportion of fiber cells of Rbpj and Jag1 conditional mutant lenses, Notch2 is not required for AEL proliferation, suggesting that a different receptor regulates this process. Instead, we found that the Notch2 normally blocks progenitor cell death. Overall, we conclude that Notch2-mediated signaling regulates lens morphogenesis, apoptosis, cell cycle withdrawal, and secondary fiber cell differentiation. We have compared gene expression of ocular lenses of mice that are lens specific conditional mutants of Notch2 gene to that of littermate controls that had no ablation of Notch2 gene in the lens. Two lenses of each of the three conditional mutants and controls were pooled together and total RNA was harvested from embryonic day 19.5 (E19.5) lenses. Gene expression changes caused by absence of Notch2 gene in the lens were analyzed.
2011-12-31 | E-GEOD-31643 | biostudies-arrayexpress
Project description:Methylation at cytosines (mCG) is a well-known regulator of gene expression but its requirements for cellular differentiation have yet to be fully elucidated. A well-studied cellular differentiation model system is the eye lens, consisting of a single anterior layer of epithelial cells that migrate laterally and differentiate into a core of fiber cells. Here, we explore the genome-wide relationships between mCG methylation, chromatin accessibility and gene expression during differentiation of eye lens epithelial cells into fiber cells. Whole genome bisulfite sequencing identified 7621 genomic loci exhibiting significant differences in mCG levels between lens epithelial and fiber cells. Changes in mCG levels were inversely correlated with the differentiation state-specific expression of 1285 genes preferentially expressed in either lens fiber or lens epithelial cells (Pearson correlation r = -0.37, p < 1x10-42). mCG levels were inversely correlated with chromatin accessibility determined by Assay for transposase-accessible sequencing (ATAC-seq) (Pearson correlation r = -0.86, p < 1x10-300). Many of the genes exhibiting altered regions of DNA methylation, chromatin accessibility and gene expression levels in fiber cells relative to epithelial cells are associated with lens fiber cell structure, homeostasis and transparency. These include lens crystallins (CRYBA4, CRYBB1, CRYGN, CRYBB2), lens beaded filament proteins (BFSP1, BFSP2), transcription factors (HSF4, SOX2, HIF1A), and Notch signaling pathway members (NOTCH1, NOTCH2, HEY1, HES5). Analysis of regions exhibiting cell-type specific alterations in DNA methylation revealed an overrepresentation of consensus sequences of multiple transcription factors known to play key roles in lens cell differentiation including HIF1A, SOX2, and the MAF family of transcription factors. Collectively, these results link DNA methylation with control of chromatin accessibility and gene expression changes required for eye lens differentiation. The results also point to a role for DNA methylation in the regulation of transcription factors previously identified to be important for lens cell differentiation.
2022-03-31 | GSE196629 | GEO
Project description:Methylation at cytosines (mCG) is a well-known regulator of gene expression but its requirements for cellular differentiation have yet to be fully elucidated. A well-studied cellular differentiation model system is the eye lens, consisting of a single anterior layer of epithelial cells that migrate laterally and differentiate into a core of fiber cells. Here, we explore the genome-wide relationships between mCG methylation, chromatin accessibility and gene expression during differentiation of eye lens epithelial cells into fiber cells. Whole genome bisulfite sequencing identified 7621 genomic loci exhibiting significant differences in mCG levels between lens epithelial and fiber cells. Changes in mCG levels were inversely correlated with the differentiation state-specific expression of 1285 genes preferentially expressed in either lens fiber or lens epithelial cells (Pearson correlation r = -0.37, p < 1x10-42). mCG levels were inversely correlated with chromatin accessibility determined by Assay for transposase-accessible sequencing (ATAC-seq) (Pearson correlation r = -0.86, p < 1x10-300). Many of the genes exhibiting altered regions of DNA methylation, chromatin accessibility and gene expression levels in fiber cells relative to epithelial cells are associated with lens fiber cell structure, homeostasis and transparency. These include lens crystallins (CRYBA4, CRYBB1, CRYGN, CRYBB2), lens beaded filament proteins (BFSP1, BFSP2), transcription factors (HSF4, SOX2, HIF1A), and Notch signaling pathway members (NOTCH1, NOTCH2, HEY1, HES5). Analysis of regions exhibiting cell-type specific alterations in DNA methylation revealed an overrepresentation of consensus sequences of multiple transcription factors known to play key roles in lens cell differentiation including HIF1A, SOX2, and the MAF family of transcription factors. Collectively, these results link DNA methylation with control of chromatin accessibility and gene expression changes required for eye lens differentiation. The results also point to a role for DNA methylation in the regulation of transcription factors previously identified to be important for lens cell differentiation.
2022-03-31 | GSE196630 | GEO
Project description:ARMMs (arrestin domain-containing protein 1 [ARRDC1]-mediated microvesicles) are extracellular vesicles that bud directly atthe plasma membrane. However, little is known about the physiological function of these vesicles. Here we report that secreted ARMMs contain active NOTCH receptors and mediate a non-canonical intercellular NOTCH signaling. Masss pectrometry of purified ARMMs identifiedNOTCH2 as a protein component of the vesicles. The NOTCH protein in ARMMs contains the critical intracellular region (NICD) that is required for its transcriptional activity in the nucleus. ARRDC1 overexpression increased the NOTCH2 incorporation into ARMMs. Conversely, CRISPR-mediated knockout of ARRDC1 dramatically reduced the amount of NOTCH2 in secreted ARMMs. The incorporation of NOTCH2 into ARMMs is facilitated by the ITCH E3 ligase and ADAM10, which are also secreted into ARMMs. We showed NOTCH2 in ARMMs delivered into recipient cells is further activated by γ-secretase cleavage to induce NOTCH-specific signaling in recipient cells. Together, our findings revealed a role for ARMMs in a novelNOTCH signaling pathway that acts in distance beyond direct cell-cell contact.
2017-10-11 | PXD006416 | Pride
Project description:During kidney development, Notch signaling plays multiple roles including promoting differentiation of nephron progenitors that give rise to all of the epithelial cells found in the nephron. Little is known about what genes Notch signaling regulates and how Notch signaling interacts with other transcription factors. To address this, we carried out genome-wide mapping of Notch2, a major Notch receptor required for differentiation of nephron progenitors, in the embryonic kidney.
2024-11-01 | GSE76249 | GEO
Project description:Background: FGF signaling controls numerous processes during cell lineage specification, organogenesis and terminal differentiation. In lens, FGF signaling was implicated as the key pathway that controls lens fiber cell differentiation, but little is known about its full range and spectrum of regulated genes. Results: Herein, we employed rat lens epithelial explant system and performed RNA and microRNA expression profiling in cells induced to differentiate by FGF2. The primary data were collected at explants grown overnight in the presence of 5 ng/ml of FGF2, followed by a treatment with 100 ng/ml of FGF2 and collection of samples at 2, 4, 12 and 24 hours. Global analysis identified extensive FGF2-regulated cellular responses that were both independent and dependent on microRNAs (miRNAs). We identified a total number of 131 FGF2-regulated miRNAs. Forty-four of these microRNAs had at least two predicted and inversely regulated target RNA molecules. The genes regulated by the highest number of miRs include Nfib, Nfat5, c-Maf, Ets1 and N-Myc, all encoding DNA-binding transcription factors. Analysis of RNA data revealed that activated FGF signaling influenced other major signaling pathways known to regulate lens differentiation including BMP/TGF-M-NM-2, Notch, and Wnt signaling. In the M-bM-^@M-^\earlyM-bM-^@M-^] response phase (2-4 hours), miRNAs targeted expression of batteries of genes that control transcription, cell death, cell proliferation, cell junction, and protein serine/threonine kinase activity. In M-bM-^@M-^\lateM-bM-^@M-^] stages (12-24 hours), the main miRNA targets included regulators of cell cycle arrest and cellular differentiation. Specific miRNA:mRNA interaction networks were identified for c-Maf, N-Myc, and Nfib (DNA-binding transcription factors); Cnot6, Dicer1, Fbx33 and Wdr47 (RNA processing); Ash1l, Med1/PBP and Kdm5b (chromatin remodeling); and c-Maf, Ets1 and Stc1 (FGF signaling). MicroRNAs including miR-9, -143, -155, -455 and -543 downregulated expression of c-Maf in the 3M-bM-^@M-^Y-UTR luciferase reporter asssays. The functional requirement for miRNAs in lens was further demonstrated via disrupted lens fiber cell differentiation in lenses with inactivated Dicer1. Conclusions: These studies demonstrate for the first time global impact of activated FGF signaling in lens cell culture system and identified novel gene regulatory networks (GRNs) connected by multiple miRNAs. Differential gene expression of FGF2-treated lens cell cultures was analyzed at 0, 2, 4, 12 and 24 hours following the treatment. Two biological replicate experiments were performed.
2013-09-06 | E-GEOD-50604 | biostudies-arrayexpress
Project description:Genome-wide approach to identify the cell-autonomous role of Brg1 in lens fiber cell terminal differentiation. To examine roles of Brg1 in mouse lens development, a dnBrg1 transgenic construct was expressed using the lens-specific alphaA-crystallin promoter in postmitotic lens fiber cells. Morphological studies revealed abnormal lens fiber cell differentiation in transgenic lenses resulting in cataract. Electron microscopic studies showed abnormal lens suture formation and incomplete karyolysis (denucleation) of lens fiber cells. To identify genes regulated by Brg1, RNA expression profiling was performed in E15.5 embryonic wild type and dnBrg1 transgenic lenses. In addition, comparisons between differentially expressed genes in dnBrg1 transgenic, Pax6 heterozygous, and Hsf4 homozygous lenses identified multiple genes co-regulated by Brg1, Hsf4 and Pax6. Among them DNase IIbeta, a key enzyme required for lens fiber cell denucleation, was found downregulated in each of the Pax6, Brg1 and Hsf4 model systems. Lens-specific deletion of Brg1 using conditional gene targeting demonstrated that Brg1 was required for lens fiber cell differentiation and indirectly for retinal development but was not essential for lens lineage formation. Wild type and dnBrg1 transgenic lenses, 4 biological replicates each
2011-01-01 | E-GEOD-22322 | biostudies-arrayexpress
Project description:Summary
Extracellular vesicles (EVs) facilitate intercellular communication by transferring cargo between cells in a variety of tissues. However, how EVs achieve cell type-specific intercellular communication is still largely unknown. We found that Notch1 and Notch2 proteins are expressed on the surface of neuronal EVs that have been generated in response to neuronal excitatory synaptic activity. Notch ligands bind these EVs on the neuronal plasma membrane, trigger their internalization, activate the Notch signaling pathway, and drive the expression of Notch target genes. The generation of these neuronal EVs requires the ESCRT-associated protein Alix. Adult Alix conditional knockout mice have reduced hippocampal Notch signaling activation and glutamatergic synaptic protein expression. Thus, EVs facilitate neuron to neuron communication via the Notch receptor-ligand system in the brain.
2023-12-06 | MSV000093592 | MassIVE
Project description:Notch signaling relies on ligand-induced proteolysis to liberate a nuclear effector that drives cell fate decisions. The location and timing of individual steps required for proteolysis and movement of Notch from membrane to nucleus, however, remain unclear. Here, we use proximity labeling with quantitative multiplexed mass spectrometry to monitor the microenvironment of endogenous Notch2 after ligand stimulation in the presence of a gamma secretase inhibitor and then as a function of time after inhibitor removal. Our studies show that gamma secretase cleavage of Notch2 occurs in an intracellular compartment and that formation of nuclear complexes and recruitment of chromatin-modifying enzymes occurs within 45 minutes of inhibitor washout. This work provides a spatiotemporal map of unprecedented detail tracking the itinerary of Notch from membrane to nucleus after activation and identifies molecular events in signal transmission that are potential targets for modulating Notch signaling activity.
2023-08-02 | PXD042123 | Pride
Project description:Notch signaling relies on ligand-induced proteolysis to liberate a nuclear effector that drives cell fate decisions. The location and timing of individual steps required for proteolysis and movement of Notch from membrane to nucleus, however, remain unclear. Here, we use proximity labeling with quantitative multiplexed mass spectrometry to monitor the microenvironment of endogenous Notch2 after ligand stimulation in the presence of a gamma secretase inhibitor and then as a function of time after inhibitor removal. Our studies show that gamma secretase cleavage of Notch2 occurs in an intracellular compartment and that formation of nuclear complexes and recruitment of chromatin-modifying enzymes occurs within 45 minutes of inhibitor washout. This work provides a spatiotemporal map of unprecedented detail tracking the itinerary of Notch from membrane to nucleus after activation and identifies molecular events in signal transmission that are potential targets for modulating Notch signaling activity.
2023-07-03 | PXD039008 | Pride