Transcriptional profiling was utilized to define the biological pathways of gingival epithelial cells modulated by mono- and complex co-culture with oral commensal S. gordonii and pathogenic P. gingivalis.
The degree of microbiome complexity influences the epithelial response to infection.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Polycomb repressive complex 2 (PRC2) silences genes responsible for neurodegeneration.
Age, Specimen part
View SamplesNormal brain function critically depends on the interaction between highly specialized neurons that operate within anatomically and functionally distinct brain regions. The fidelity of neuronal specification is contingent upon the robustness of the transcriptional program that supports the neuron type-specific patterns of gene expression. Changes in neuron type-specific gene expression are commonly associated with neurodegenerative disorders including Huntingtons and Alzheimers disease. The neuronal specification is driven by gene expression programs that are established during early stages of neuronal development and remain in place in the adult brain. Here we show that the Polycomb repressive complex 2 (PRC2), which supports neuron specification during early differentiation, contributes to the suppression of the transcription program that can be detrimental for the adult neuron function. We show that PRC2 deficiency in adult striatal neurons and in cerebellar Purkinje cells impairs the maintenance of neuron-type specific gene expression. The deficiency in PRC2 has a direct impact on a selected group of genes that is dominated by self-regulating transcription factors normally suppressed in these neurons. The age-dependent progressive transcriptional changes in PRC2-deficient neurons are associated with impaired neuronal function and survival and lead to the development of fatal neurodegenerative disorders in mice.
Polycomb repressive complex 2 (PRC2) silences genes responsible for neurodegeneration.
No sample metadata fields
View SamplesGene expression (mRNA) profiling of human ependymomas
Delineation of two clinically and molecularly distinct subgroups of posterior fossa ependymoma.
Sex, Age, Specimen part
View SamplesDuring fasting, increases in circulating pancreatic glucagon maintain glucose balance by up-regulating hepatic gluconeogenesis. Triggering of the cAMP pathway stimulates the gluconeogenic program through the phosphorylation of CREB and via the de-phosphorylation of the CREB coactivator CRTC2. Hormonal and nutrient signals are also thought to modulate gluconeogenic genes by promoting epigenetic changes that facilitate assembly of the transcriptional machinery, although the nature of these modifications is unclear. Here we show that histone H3 acetylation at Lys 9 (H3K9Ac) is elevated over gluconeogenic genes during fasting and in diabetes, where it contributes to increases in hepatic glucose production. Following its dephosphorylation, CRTC2 promoted increases in H3K9Ac by mediating the recruitment of the lysine acetyltransferase 2B (KAT2B) and WD repeat-containing protein 5 (WDR5), a core subunit of histone methyltransferase (HMT) complexes. In turn, KAT2B and WDR5 stimulated the gluconeogenic program through a self-reinforcing cycle whereby increases in H3K9Ac further potentiated CRTC2 occupancy at CREB binding sites. Breaking this cycle, by depletion of KAT2B or WDR5, decreased gluconeogenic gene expression. As administration of a small molecule KAT2B antagonist lowered circulating blood glucose concentrations in insulin resistance, our results demonstrate how this enzyme may be a useful target for diabetes treatment.
Glucagon regulates gluconeogenesis through KAT2B- and WDR5-mediated epigenetic effects.
Sex, Age, Specimen part
View SamplesMitochondrial biogenesis is regulated by signaling pathways sensitive to extracellular conditions and to the internal environment of the cell. We found that deletion of protein phosphatase 2A (PP2A) or of protein phosphatase 6 (PP6) diminishes the nuclear transcriptional response associated with mtDNA damage. Overall design: Six samples were analyzed to determine message RNA levels.
Deletion of conserved protein phosphatases reverses defects associated with mitochondrial DNA damage in Saccharomyces cerevisiae.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Acute depletion of Tet1-dependent 5-hydroxymethylcytosine levels impairs LIF/Stat3 signaling and results in loss of embryonic stem cell identity.
Specimen part, Cell line
View SamplesThe TET family of FE(II) and 2-oxoglutarate-dependent enzymes (Tet1/2/3) promote DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which they further oxidize into 5-formylcytosine and 5-carboxylcytosine. Tet1 is robustly expressed in mouse embryonic stem cells (mESCs) and has been implicated in mESC maintenance. Here we demonstrate that, unlike genetic deletion, RNAi-mediated depletion of Tet1 in mESCs led to a significant reduction in 5hmC and loss of mESC identity. The differentiation phenotype due to Tet1 depletion positively correlated with the extent of 5hmC loss. Meta-analyses of genomic datasets suggested interaction between Tet1 and leukemia inhibitory factor (LIF) signaling. LIF signaling is known to promote self-renewal and pluripo-tency in mESCs partly by opposing MAPK/ERK mediated differentiation. Withdrawal of LIF leads to differentiation of mESCs. We discovered that Tet1 depletion impaired LIF-dependent Stat3-mediated gene activation by affecting Stat3's ability to bind to its target sites on chromatin. Nanog overexpression or inhibition of MAPK/ERK signaling, both known to maintain mESCs in the absence of LIF, rescued Tet1 depletion, further supporting the dependence of LIF/Stat3 signaling on Tet1. These data support the conclusion that analysis of mESCs in the hours/days immediately following efficient Tet1 depletion reveals Tet1s normal physiological role in maintaining the pluripotent state that may be subject to homeostatic compensation in genetic models.
Acute depletion of Tet1-dependent 5-hydroxymethylcytosine levels impairs LIF/Stat3 signaling and results in loss of embryonic stem cell identity.
Cell line
View SamplesAnalysis of gene expression of Pdx-EGFP1+ pancreatic progenitors before or after co-culture at mRNA level. The hypothesis tested in the study was that the overall gene expression in Pdx1-EGFP+ does not alter after co-culture with endothelial cells. The result supported our hypothesis. Overall design: Total RNA isolated from Pdx1-EGFP+ progenitors from the Pdx1-EGFP HUES8 cell-derived pancreatic progenitor population before (none) and after co-culture (AKT-HUVEC, MPEC, or BJ) Fig 2d in publication.
Endothelial cells control pancreatic cell fate at defined stages through EGFL7 signaling.
No sample metadata fields
View SamplesTo estimate mRNA steady-state levels we used RNA extracted from logarithmically growing fisson yeast cells on Affymetrix Yeast 2.0 Genechip arrays. The signal intensities from two independent biological repeats were averaged, resulting in measurements for 4818 out of 4962 nuclear protein-coding genes.
A network of multiple regulatory layers shapes gene expression in fission yeast.
Sex, Subject
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