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Mus musculus
3 Downloadable Samples
Description
The Polycomb group (PcG) gene products mediate heritable silencing of developmental regulators in metazoans, participating in one of two distinct multimeric protein complexes, the Polycomb repressive complexes-1 (PRC1) and -2 (PRC2)1-5. PRC2 catalyses trimethylation of histone H3 at lysine 27 (H3K27) which in turn is thought to provide a recruitment site for PRC13-7. Recent studies demonstrate that mono-ubiquitylation of histone H2A at lysine 119 is important in PcG mediated silencing with the core PRC1 component Ring1A/B functioning as the E3 ligase8. PRC2 has been shown to share target genes with the core transcription network to maintain embryonic stem (ES) cells including Oct4 and Nanog9. Here we identify an essential role for PRC1 in repressing developmental regulators in ES cells, and thereby in maintaining ES cell pluripotency. A significant proportion of the PRC1 target genes are also repressed by Oct4. We demonstrate that engagement of PRC1 and PRC2 at target genes is Oct4-dependent and moreover that Ring1B interacts with Oct4. Collectively these results show that PcG complexes are instrumental in Oct4-dependent repression required to maintain pluripotency of ES cells. This study provides a first functional link between a core ES cell regulator and global epigenetic regulation of the genome.
Publication Title
Polycomb group proteins Ring1A/B are functionally linked to the core transcriptional regulatory circuitry to maintain ES cell identity.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 12 Downloadable Samples
Description
Two distinct Polycomb complexes, PRC1 and PRC2, collaborate to maintain epigenetic repression of key developmental loci in embryonic stem cells (ESCs). PRC1 and PRC2 have histone modifying activities, catalyzing mono-ubiquitination of histone H2A (H2AK119u1) and trimethylation of H3 lysine 27 (H3K27me3) respectively. Compared to H3K27me3, localization and role of H2AK119ub1 is not fully understood in ESCs. Here we present genome-wide H2AK119u1 maps in ESCs and identify a group of genes at which H2AK119u1 is deposited in a Ring1-dependent manner. These genes are a distinctive subset of genes with H3K27me3 enrichment and are the central targets of Polycomb silencing that are required to maintain ESC identity. We further show that the H2A ubiquitination activity of PRC1 is dispensable for its target binding and its activity to compact chromatin at Hox loci, but is indispensable for efficient repression of target genes and thereby ESC maintenance. These data demonstrate that multiple effector mechanisms including H2A ubiquitination and chromatin compaction combine to mediate PRC1-dependent repression of genes that are crucial for the maintenance of ESC identity. Utilization of these diverse effector mechanisms might provide a means to maintain a repressive state that is robust yet highly responsive to developmental cues during ES cell self-renewal and differentiation.
Publication Title
Histone H2A mono-ubiquitination is a crucial step to mediate PRC1-dependent repression of developmental genes to maintain ES cell identity.
Sample Metadata Fields
Specimen part, Cell line, Treatment
View Samples- Mus musculus
- 12 Downloadable Samples
Description
We used microarrays to investigate the restoration of repression of PRC1 target gene expression in Ring1A/B-dKO ES cells stably expressing either of mock, WT or mutant Ring1B construct.
Publication Title
Histone H2A mono-ubiquitination is a crucial step to mediate PRC1-dependent repression of developmental genes to maintain ES cell identity.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus, Homo sapiens
- 4 Downloadable Samples
Description
Mutations in the PTEN, TP53 and RB1 pathways are obligate events in the pathogenesis of human glioblastomas, the highest grade of astrocytoma. To investigate synergy between these tumor suppressors in mice, we induced various combinations of compound deletions conditionally in astrocytes and neural precursors in the mature brain. The resulting highly penetrant astrocytomas showed a spectrum of histopathological variation reminiscent of human tumors, and ranged from grade III to grade IV (glioblastoma). Secondary somatic mutations varied depending on the combination of initiating deletions and were relevant to human disease. Receptor tyrosine kinase amplifications were frequent in tumors initiated by combined conditional deletion of Pten and Tp53, but not when Rb, Pten and Tp53 were simultaneously deleted. Multiple mutations within PI3K and Rb pathways were acquired, however, Mapk activation was not consistently detected in astrocytomas. Gene expression profiling revealed striking similarities to previously described human astrocytoma subclasses. A subset of astrocytomas initiated outside of proliferative niches in the adult brain.
Publication Title
Cooperativity within and among Pten, p53, and Rb pathways induces high-grade astrocytoma in adult brain.
Sample Metadata Fields
Sex, Specimen part
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GSE33516- Mus musculus
- 2 Downloadable Samples
Description
We used microarray analysis to identify specific molecular mechanisms controlling IL-5 transcription in memory Th2 cells.
Publication Title
Eomesodermin controls interleukin-5 production in memory T helper 2 cells through inhibition of activity of the transcription factor GATA3.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 4 Downloadable Samples
Description
Analysis of differentiating LSD1-KD C2C12 myoblasts. We found LSD1 is an important regulator of oxidative phenotypes in skeletal muscle cells.
Publication Title
LSD1 mediates metabolic reprogramming by glucocorticoids during myogenic differentiation.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 27 Downloadable Samples
Description
In a transgenic mouse model of Alzheimer disease (AD), cleavage of the amyloid precursor protein (APP) by the -secretase ADAM10 prevented amyloid plaque formation and alleviated cognitive deficits. Furthermore, there was a positive influence of ADAM10 over-expression on neurotransmitter-specific formation of synapses and on synaptic plasticity.
Publication Title
Differential gene expression in ADAM10 and mutant ADAM10 transgenic mice.
Sample Metadata Fields
Sex, Age
View Samples- Mus musculus
- 2 Downloadable Samples
Description
Naturally occurring CD25+CD4+ regulatory T cells (T reg cells) are currently intensively characterized because of their major importance in modulating host responses to tumors and infections, in preventing transplant rejection, and in inhibiting the development of autoimmunity and allergy. Originally, CD4+ T reg cells were identified exclusively by the constitutive expression of CD25, and many in vivo experiments have been performed using depleting antibodies directed against CD25. However, both the existence of CD25 T reg cells, especially within peripheral tissues, as well as the expression of CD25 on activated conventional T cells, which precludes discrimination between T reg cells and activated conventional T cells, limits the interpretation of data obtained by the use of anti-CD25 depleting antibodies. The most specific T reg cell marker currently known is the forkhead box transcription factor Foxp3, which has been shown to be expressed specifically in mouse CD4+ T reg cells and acts as a master switch in the regulation of their development and function. To address the question of the in vivo role of T reg cells in immunopathology, we have generated bacterial artificial chromosome (BAC)transgenic mice termed depletion of regulatory T cell (DEREG) mice, which express a diphtheria toxin receptor (DTR) enhanced GFP (eGFP) fusion protein under the control of the foxp3 locus, allowing both detection and inducible depletion of Foxp3+ T reg cells. The gene expression profile of both CD4+eGFP+FoxP3+ and CD4+eGFPnegFoxP3neg cells isolated from DEREG mice was here analyzed by micro array.
Publication Title
Immunostimulatory RNA blocks suppression by regulatory T cells.
Sample Metadata Fields
Specimen part
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